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Gabrielli F, Bernasconi E, Toscano A, Avossa A, Cavicchioli A, Andreone P, Gitto S. Side Effects of Immunosuppressant Drugs After Liver Transplant. Pharmaceuticals (Basel) 2025; 18:342. [PMID: 40143120 PMCID: PMC11946649 DOI: 10.3390/ph18030342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2025] [Revised: 02/18/2025] [Accepted: 02/26/2025] [Indexed: 03/28/2025] Open
Abstract
Liver transplantation (LT) is the standard of care for both end-stage liver failure and hepatocellular carcinoma (HCC). Side effects of the main used immunosuppressive drugs have a noteworthy impact on the long-term outcome of LT recipients. Consequently, to achieve a balance between optimal immunosuppression and minimal side effects is a cornerstone of the post-LT period. Today, there are no validated markers for overimmunosuppression and underimmunosuppression, only a few drugs have therapeutic drug monitoring, and immunosuppression regimens vary from center to center and from country to country. Currently, there are many drugs with different efficacy and safety profiles. Using different agents permits a decrease in the dosage and minimizes the toxicities. A small subset of recipients achieves immunotolerance with the chance to stop immunosuppressive therapy. This article focuses on the side effects of immunosuppressive drugs, which significantly impact long-term outcomes for LT recipients. The primary aim is to highlight the balance between achieving effective immunosuppression and minimizing adverse effects, emphasizing the role of personalized therapeutic strategies. Moreover, this review evaluates the mechanisms of action and specific complications associated with immunosuppressive agents. Finally, special attention is given to strategies for reducing immunosuppressive burdens, improving patient quality of life, and identifying immunotolerant individuals.
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Affiliation(s)
- Filippo Gabrielli
- Internal and Metabolic Medicine, Department of Medical and Surgical Sciences for Children & Adults, AOU of Modena, University of Modena and Reggio Emilia, 41126 Modena, Italy
| | - Elisa Bernasconi
- Postgraduate School of Internal Medicine, University of Modena and Reggio Emilia, 41126 Modena, Italy
| | - Arianna Toscano
- Division of Internal Medicine, University Hospital of Policlinico G. Martino, 98124 Messina, Italy
| | - Alessandra Avossa
- Department of Experimental and Clinical Medicine, University of Florence, 50134 Florence, Italy
| | - Alessia Cavicchioli
- Internal and Metabolic Medicine, Department of Medical and Surgical Sciences for Children & Adults, AOU of Modena, University of Modena and Reggio Emilia, 41126 Modena, Italy
| | - Pietro Andreone
- Internal and Metabolic Medicine, Department of Medical and Surgical Sciences for Children & Adults, AOU of Modena, University of Modena and Reggio Emilia, 41126 Modena, Italy
- Postgraduate School of Allergology and Clinical Immunology, University of Modena and Reggio Emilia, 41126 Modena, Italy
| | - Stefano Gitto
- Department of Experimental and Clinical Medicine, University of Florence, 50134 Florence, Italy
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Nakahara T, Fujimoto S, Jinzaki M. Molecular imaging of cardiovascular disease: Current status and future perspective. J Cardiol 2025:S0914-5087(25)00017-6. [PMID: 39922562 DOI: 10.1016/j.jjcc.2025.01.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2024] [Revised: 01/15/2025] [Accepted: 01/28/2025] [Indexed: 02/10/2025]
Abstract
Advancements in knowledge of cardiovascular disease, pharmacology, and chemistry have led to the development of newer radiopharmaceuticals and targets for new and more suitable molecules. Molecular imaging encompasses multiple imaging techniques for identifying the characteristics of key components involved in disease. Despite its limitations in spatial resolution, the affinity for key molecules compensates for disadvantages in diagnosing diseases and elucidating their pathophysiology. This review introduce established molecular tracers involved in clinical practice and emerging tracers already applied in clinical studies, classifying the key component in A: artery, specifically those vulnerable plaque (A-I) inflammatory cells [18F-FDG]; A-II) lipid/fatty acid; A-III) hypoxia; A-IV) angiogenesis; A-V) protease [18F/68Ga-FAPI]; A-VI) thrombus/hemorrhage; A-VII) apoptosis and A-VIII) microcalcification [18F-NaF]) and B: myocardium, including myocardial ischemia, infarction and myocardiopathy (B-I) myocardial ischemia; B-II) myocardial infarction (myocardial damage and fibrosis); B-III) myocarditis and endocarditis; B-IV) sarcoidosis; B-V) amyloidosis; B-VI) metabolism; B-VII) innervation imaging). In addition to cardiovascular-specific tracers tested in animal models, many radiotracers may have been developed in other areas, such as oncology imaging or neuroimaging. While this review does not cover all available tracers, some of them hold potential for future use assessing cardiovascular disease. Advances in molecular biology, pharmaceuticals, and imaging sciences will facilitate the identification of precise disease mechanisms, enabling precise diagnoses, better assessment of disease status, and enhanced therapeutic evaluation in this multi-modality era.
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Affiliation(s)
- Takehiro Nakahara
- Department of Radiology, Keio University School of Medicine, Tokyo, Japan.
| | - Shinichiro Fujimoto
- Department of Cardiovascular Biology and Medicine, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Masahiro Jinzaki
- Department of Radiology, Keio University School of Medicine, Tokyo, Japan
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Mizuno A, Toyama T, Ichikawa A, Sakai N, Yoshioka Y, Nishito Y, Toga R, Amesaka H, Kaneko T, Arisawa K, Tsutsumi R, Mita Y, Tanaka SI, Noguchi N, Saito Y. An efficient selenium transport pathway of selenoprotein P utilizing a high-affinity ApoER2 receptor variant and being independent of selenocysteine lyase. J Biol Chem 2023; 299:105009. [PMID: 37406814 PMCID: PMC10407282 DOI: 10.1016/j.jbc.2023.105009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 06/22/2023] [Accepted: 06/23/2023] [Indexed: 07/07/2023] Open
Abstract
Selenoprotein P (SeP, encoded by the SELENOP gene) is a plasma protein that contains selenium in the form of selenocysteine residues (Sec, a cysteine analog containing selenium instead of sulfur). SeP functions for the transport of selenium to specific tissues in a receptor-dependent manner. Apolipoprotein E receptor 2 (ApoER2) has been identified as a SeP receptor. However, diverse variants of ApoER2 have been reported, and the details of its tissue specificity and the molecular mechanism of its efficiency remain unclear. In the present study, we found that human T lymphoma Jurkat cells have a high ability to utilize selenium via SeP, while this ability was low in human rhabdomyosarcoma cells. We identified an ApoER2 variant with a high affinity for SeP in Jurkat cells. This variant had a dissociation constant value of 0.67 nM and a highly glycosylated O-linked sugar domain. Moreover, the acidification of intracellular vesicles was necessary for selenium transport via SeP in both cell types. In rhabdomyosarcoma cells, SeP underwent proteolytic degradation in lysosomes and transported selenium in a Sec lyase-dependent manner. However, in Jurkat cells, SeP transported selenium in Sec lyase-independent manner. These findings indicate a preferential selenium transport pathway involving SeP and high-affinity ApoER2 in a Sec lyase-independent manner. Herein, we provide a novel dynamic transport pathway for selenium via SeP.
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Affiliation(s)
- Ayako Mizuno
- Laboratory of Molecular Biology and Metabolism, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Takashi Toyama
- Laboratory of Molecular Biology and Metabolism, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Atsuya Ichikawa
- Laboratory of Molecular Biology and Metabolism, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Naoko Sakai
- The Systems Life Sciences Laboratory, Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Japan
| | - Yuya Yoshioka
- The Systems Life Sciences Laboratory, Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Japan
| | - Yukina Nishito
- The Systems Life Sciences Laboratory, Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Japan
| | - Renya Toga
- Laboratory of Biostructural Chemistry, Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Kyoto, Japan
| | - Hiroshi Amesaka
- Laboratory of Biostructural Chemistry, Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Kyoto, Japan
| | - Takayuki Kaneko
- Laboratory of Molecular Biology and Metabolism, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Kotoko Arisawa
- Laboratory of Molecular Biology and Metabolism, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Ryouhei Tsutsumi
- Laboratory of Molecular Biology and Metabolism, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan
| | - Yuichiro Mita
- The Systems Life Sciences Laboratory, Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Japan
| | - Shun-Ichi Tanaka
- Laboratory of Biostructural Chemistry, Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Kyoto, Japan; Department of Biotechnology, College of Life Sciences, Ritsumeikan University, Shiga, Japan
| | - Noriko Noguchi
- The Systems Life Sciences Laboratory, Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Japan
| | - Yoshiro Saito
- Laboratory of Molecular Biology and Metabolism, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai, Japan; The Systems Life Sciences Laboratory, Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Japan.
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Carmenate T, Montalvo G, Lozada SL, Rodriguez Y, Ortiz Y, Díaz C, Avellanet J, Kim J, Surh CD, Graça L, León K. The antitumor effect induced by an IL-2 ‘no-alpha’ mutein depends on changes in the CD8+ T lymphocyte/Treg cell balance. Front Immunol 2022; 13:974188. [PMID: 36059465 PMCID: PMC9428827 DOI: 10.3389/fimmu.2022.974188] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 07/27/2022] [Indexed: 11/18/2022] Open
Abstract
High doses of interleukin-2 (IL-2) have been used for the treatment of melanoma and renal cell carcinoma, but this therapy has limited efficacy, with a ~15% response rate. Remarkably, 7%–9% of patients achieve complete or long-lasting responses. Many patients treated with IL-2 experienced an expansion of regulatory T cells (Tregs), specifically the expansion of ICOS+ highly suppressive Tregs, which correlate with worse clinical outcomes. This partial efficacy together with the high toxicity associated with the therapy has limited the use of IL-2-based therapy. Taking into account the understanding of IL-2 structure, signaling, and in vivo functions, some efforts to improve the cytokine properties are currently under study. In previous work, we described an IL-2 mutein with higher antitumor activity and less toxicity than wtIL-2. Mutein was in silico designed for losing the binding capacity to CD25 and for preferential stimulation of effector cells CD8+ and NK cells but not Tregs. Mutein induces a higher anti-metastatic effect than wtIL-2, but the extent of the in vivo antitumor activity was still unexplored. In this work, it is shown that mutein induces a strong antitumor effect on four primary tumor models, being effective even in those models where wtIL-2 does not work. Furthermore, mutein can change the in vivo balance between Tregs and T CD8+ memory/activated cells toward immune activation, in both healthy and tumor-bearing mice. This change reaches the tumor microenvironment and seems to be the major explanation for mutein efficacy in vivo.
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Affiliation(s)
- Tania Carmenate
- Immune Regulation Department, Centro de Inmunología Molecular, Havana, Cuba
- *Correspondence: Tania Carmenate,
| | - Galia Montalvo
- Immune Regulation Department, Centro de Inmunología Molecular, Havana, Cuba
| | - Sum Lai Lozada
- Immune Regulation Department, Centro de Inmunología Molecular, Havana, Cuba
| | - Yaretnis Rodriguez
- Immune Regulation Department, Centro de Inmunología Molecular, Havana, Cuba
| | - Yaquelin Ortiz
- Immune Regulation Department, Centro de Inmunología Molecular, Havana, Cuba
| | - Claudia Díaz
- Immune Regulation Department, Centro de Inmunología Molecular, Havana, Cuba
| | - Janet Avellanet
- Immune Regulation Department, Centro de Inmunología Molecular, Havana, Cuba
| | - Juhee Kim
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science 12 and Technology (POSTECH), Pohang, South Korea
| | - Charles D. Surh
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science 12 and Technology (POSTECH), Pohang, South Korea
| | - Luis Graça
- Instituto de Medicina Molecular, Faculdade de Medici na da Universidade de Lisboa, Lisbon, Portugal
| | - Kalet León
- Immune Regulation Department, Centro de Inmunología Molecular, Havana, Cuba
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Holder PG, Lim SA, Huang CS, Sharma P, Dagdas YS, Bulutoglu B, Sockolosky JT. Engineering interferons and interleukins for cancer immunotherapy. Adv Drug Deliv Rev 2022; 182:114112. [PMID: 35085624 DOI: 10.1016/j.addr.2022.114112] [Citation(s) in RCA: 73] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Revised: 01/07/2022] [Accepted: 01/12/2022] [Indexed: 02/08/2023]
Abstract
Cytokines are a class of potent immunoregulatory proteins that are secreted in response to various stimuli and act locally to regulate many aspects of human physiology and disease. Cytokines play important roles in cancer initiation, progression, and elimination, and thus, there is a long clinical history associated with the use of recombinant cytokines to treat cancer. However, the use of cytokines as therapeutics has been limited by cytokine pleiotropy, complex biology, poor drug-like properties, and severe dose-limiting toxicities. Nevertheless, cytokines are crucial mediators of innate and adaptive antitumor immunity and have the potential to enhance immunotherapeutic approaches to treat cancer. Development of immune checkpoint inhibitors and combination immunotherapies has reinvigorated interest in cytokines as therapeutics, and a variety of engineering approaches are emerging to improve the safety and effectiveness of cytokine immunotherapy. In this review we highlight recent advances in cytokine biology and engineering for cancer immunotherapy.
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6
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Abstract
Lymphocyte depletion and blockade of T-cell activation and trafficking serve as therapeutic strategies for an enlarging number of immune-mediated diseases and malignancies. This review summarizes the infection risks associated to monoclonal antibodies that bind to the α chain of the interleukin-2 receptor, the cell surface glycoprotein CD52, and members of α4- and β2-integrin families acting as cell-adhesion molecules. An outline of the mechanisms of action, approved indications and off-label uses, expected impact on the host immune response, and available clinical evidence is provided for each of these agents.
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Podichetty JT, Brinda BJ, Nelson RP, Karr AH, Prasad NK, Quinney S, Foxworthy Scott S, Kiel PJ. Pharmacokinetics of Basiliximab for the Prevention of Graft-versus-Host Disease in Patients Undergoing Hematopoietic Cell Transplantation with Minimal-Intensity Cyclophosphamide and Fludarabine. Pharmacotherapy 2019; 40:26-32. [PMID: 31742732 DOI: 10.1002/phar.2347] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
STUDY OBJECTIVE Basiliximab is an immunosuppressive monoclonal antibody used for rejection prevention following solid organ transplantation; the pharmacokinetics (PK) of basiliximab in this setting are known. Basiliximab may also be used for prophylaxis and treatment of graft-versus-host disease (GVHD) in patients undergoing allogeneic hematopoietic cell transplantation (HCT); however, the PK of basiliximab in this setting are not known. Clinical transplant providers expect variation in the volume of distribution and clearance after nonmyeloablative allogeneic transplantation (NMAT) compared with solid organ transplantation. Blood loss, organ site-specific antibody accumulation, and differences in blood product use during the two transplantation approaches may generate differences in basiliximab PK. Therefore, the objective of this study was to describe the PK of basiliximab after its addition to a minimally intense NMAT regimen, in conjunction with cyclosporine, for GVHD prophylaxis in patients with hematologic malignancies. DESIGN Population PK analysis of a single-center, single-arm, phase II clinical trial. SETTING Academic cancer research center. PATIENTS Fourteen adults with hematologic malignancies (acute myeloid leukemia, acute lymphoblastic leukemia, chronic lymphocytic leukemia, myelodysplastic syndrome, non-Hodgkin's lymphoma, Hodgkin's lymphoma, myelofibrosis, or severe aplastic anemia) and undergoing NMAT with a fully HLA-matched (10 of 10 antigen matched) related or unrelated donor. MEASUREMENTS AND MAIN RESULTS Basiliximab was used in conjunction with cyclosporine to deplete activated T cells in vivo as GVHD prophylaxis. We developed a novel competitive enzyme-linked immunosorbent assay (ELISA) method using recombinant interleukin-2 receptor alpha-chain (IL-2Ra) and a commercially available soluble sIL-2R ELISA kit to permit the quantification of serum basiliximab concentrations and characterization of the PK properties of the drug in this patient population. Using a nonlinear mixed effects model with NONMEM software, a one-compartment model with first-order elimination best described the PK, as covariate analysis using stepwise covariate modeling did not improve the base model. CONCLUSION We suggest a one-compartment population model with first-order elimination to capture the PK profile for basiliximab for this patient population.
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Affiliation(s)
| | | | - Robert P Nelson
- Indiana University School of Medicine, Indianapolis, Indiana
| | | | | | - Sara Quinney
- Indiana University School of Medicine, Indianapolis, Indiana
| | | | - Patrick J Kiel
- Indiana University School of Medicine, Indianapolis, Indiana.,Indiana University Health, Indianapolis, Indiana
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Potent antitumour activity of interleukin-2-Fc fusion proteins requires Fc-mediated depletion of regulatory T-cells. Nat Commun 2017; 8:15373. [PMID: 28497796 PMCID: PMC5437307 DOI: 10.1038/ncomms15373] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 03/24/2017] [Indexed: 01/16/2023] Open
Abstract
Interleukin-2 (IL-2) is an established therapeutic agent used for cancer immunotherapy. Since treatment efficacy is mediated by CD8+ and NK cell activity at the tumour site, considerable efforts have focused on generating variants that expand these subsets systemically, as exemplified by IL-2/antibody complexes and ‘superkines'. Here we describe a novel determinant of antitumour activity using fusion proteins consisting of IL-2 and the antibody fragment crystallizable (Fc) region. Generation of long-lived IL-2-Fc variants in which CD25 binding is abolished through mutation effectively prevents unwanted activation of CD25+ regulatory T-cells (Tregs) and results in strong expansion of CD25− cytotoxic subsets. Surprisingly, however, such variants are less effective than wild-type IL-2-Fc in mediating tumour rejection. Instead, we report that efficacy is crucially dependent on depletion of Tregs through Fc-mediated immune effector functions. Our results underpin an unexpected mechanism of action and provide important guidance for the development of next generation IL-2 therapeutics. Interleukin-2 (IL-2) is a T-cell proliferating factor used for cancer immunotherapy. Here, the authors develop a long-lived variant of IL-2 that, mutated in its binding domain, drives a much more potent tumour regression by depleting CD25+ CD4+ regulatory T-cells via targeting them for phagocytosis.
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Misu H, Takayama H, Saito Y, Mita Y, Kikuchi A, Ishii KA, Chikamoto K, Kanamori T, Tajima N, Lan F, Takeshita Y, Honda M, Tanaka M, Kato S, Matsuyama N, Yoshioka Y, Iwayama K, Tokuyama K, Akazawa N, Maeda S, Takekoshi K, Matsugo S, Noguchi N, Kaneko S, Takamura T. Deficiency of the hepatokine selenoprotein P increases responsiveness to exercise in mice through upregulation of reactive oxygen species and AMP-activated protein kinase in muscle. Nat Med 2017; 23:508-516. [PMID: 28263310 DOI: 10.1038/nm.4295] [Citation(s) in RCA: 115] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Accepted: 01/27/2017] [Indexed: 02/05/2023]
Abstract
Exercise has numerous health-promoting effects in humans; however, individual responsiveness to exercise with regard to endurance or metabolic health differs markedly. This 'exercise resistance' is considered to be congenital, with no evident acquired causative factors. Here we show that the anti-oxidative hepatokine selenoprotein P (SeP) causes exercise resistance through its muscle receptor low-density lipoprotein receptor-related protein 1 (LRP1). SeP-deficient mice showed a 'super-endurance' phenotype after exercise training, as well as enhanced reactive oxygen species (ROS) production, AMP-activated protein kinase (AMPK) phosphorylation and peroxisome proliferative activated receptor γ coactivator (Ppargc)-1α (also known as PGC-1α; encoded by Ppargc1a) expression in skeletal muscle. Supplementation with the anti-oxidant N-acetylcysteine (NAC) reduced ROS production and the endurance capacity in SeP-deficient mice. SeP treatment impaired hydrogen-peroxide-induced adaptations through LRP1 in cultured myotubes and suppressed exercise-induced AMPK phosphorylation and Ppargc1a gene expression in mouse skeletal muscle-effects which were blunted in mice with a muscle-specific LRP1 deficiency. Furthermore, we found that increased amounts of circulating SeP predicted the ineffectiveness of training on endurance capacity in humans. Our study suggests that inhibitors of the SeP-LRP1 axis may function as exercise-enhancing drugs to treat diseases associated with a sedentary lifestyle.
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Affiliation(s)
- Hirofumi Misu
- Department of Endocrinology and Metabolism, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
- PRESTO, Japan Science and Technology Agency, Kawaguchi, Japan
| | - Hiroaki Takayama
- Department of Endocrinology and Metabolism, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
- Department of System Biology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
| | - Yoshiro Saito
- Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Japan
| | - Yuichiro Mita
- Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Japan
| | - Akihiro Kikuchi
- Department of Endocrinology and Metabolism, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
- Department of System Biology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
| | - Kiyo-Aki Ishii
- Department of Endocrinology and Metabolism, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
- Department of System Biology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
| | - Keita Chikamoto
- Department of System Biology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
- Division of Natural System, Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa, Japan
| | - Takehiro Kanamori
- Department of System Biology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
| | - Natsumi Tajima
- Department of System Biology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
| | - Fei Lan
- Department of System Biology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
- Department of Endocrinology and Metabolism, Chengdu First People's Hospital, Chengdu, China
| | - Yumie Takeshita
- Department of System Biology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
| | - Masao Honda
- Department of System Biology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
| | - Mutsumi Tanaka
- Diagnostic R&D, R&D Headquarters, Alfresa Pharma Corporation, Ibaraki, Japan
| | - Seiji Kato
- Diagnostic R&D, R&D Headquarters, Alfresa Pharma Corporation, Ibaraki, Japan
| | - Naoto Matsuyama
- Diagnostic R&D, R&D Headquarters, Alfresa Pharma Corporation, Ibaraki, Japan
| | - Yuya Yoshioka
- Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Japan
| | - Kaito Iwayama
- Division of Sports Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Japan
| | - Kumpei Tokuyama
- Division of Sports Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Japan
| | - Nobuhiko Akazawa
- Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan
| | - Seiji Maeda
- Faculty of Health and Sport Sciences, University of Tsukuba, Tsukuba, Japan
| | - Kazuhiro Takekoshi
- Faculty of Medicine, Division of Sports Science, University of Tsukuba, Tsukuba, Japan
| | - Seiichi Matsugo
- Division of Natural System, Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa, Japan
- Institute of Science and Engineering, Faculty of Natural System, Kanazawa University, Kanazawa, Japan
| | - Noriko Noguchi
- Department of Medical Life Systems, Faculty of Life and Medical Sciences, Doshisha University, Kyotanabe, Japan
| | - Shuichi Kaneko
- Department of System Biology, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
| | - Toshinari Takamura
- Department of Endocrinology and Metabolism, Kanazawa University Graduate School of Medical Sciences, Kanazawa, Japan
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Ponce LF, García-Martínez K, León K. Quantitative Contribution of IL2Rγ to the Dynamic Formation of IL2-IL2R Complexes. PLoS One 2016; 11:e0155684. [PMID: 27195783 PMCID: PMC4873224 DOI: 10.1371/journal.pone.0155684] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 05/03/2016] [Indexed: 11/18/2022] Open
Abstract
Interleukin-2 (IL2) is a growth factor for several immune cells and its function depends on its binding to IL2Rs in the cell membrane. The most accepted model for the assembling of IL2-IL2R complexes in the cell membrane is the Affinity Conversion Model (ACM). This model postulates that IL2R receptor association is sequential and dependent on ligand binding. Most likely free IL2 binds first to IL2Rα, and then this complex binds to IL2Rβ, and finally to IL2Rγ (γc). However, in previous mathematical models representing this process, the binding of γc has not been taken into account. In this work, the quantitative contribution of the number of IL2Rγ chain to the IL2-IL2R apparent binding affinity and signaling is studied. A mathematical model of the affinity conversion process including the γ chain in the dynamic, has been formulated. The model was calibrated by fitting it to experimental data, specifically, Scatchard plots obtained using human cell lines. This paper demonstrates how the model correctly explains available experimental observations. It was estimated, for the first time, the value of the kinetic coefficients of IL2-IL2R complexes interaction in the cell membrane. Moreover, the number of IL2R components in different cell lines was also estimated. It was obtained a variable distribution in the number of IL2R components depending on the cell type and the activation state. Of most significance, the study predicts that not only the number of IL2Rα and IL2Rβ, but also the number of γc determine the capacity of the cell to capture and retain IL2 in signalling complexes. Moreover, it is also showed that different cells might use different pathways to bind IL2 as consequence of its IL2R components distribution in the membrane.
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Affiliation(s)
- Luis F. Ponce
- Center of Molecular Immunology, System Biology Department, Habana, 11600, Cuba
- * E-mail:
| | | | - Kalet León
- Center of Molecular Immunology, System Biology Department, Habana, 11600, Cuba
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11
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Ren T, Takahashi Y, Liu X, Loughran TP, Sun SC, Wang HG, Cheng H. HTLV-1 Tax deregulates autophagy by recruiting autophagic molecules into lipid raft microdomains. Oncogene 2015; 34:334-45. [PMID: 24362528 PMCID: PMC4067462 DOI: 10.1038/onc.2013.552] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 10/14/2013] [Accepted: 11/01/2013] [Indexed: 12/13/2022]
Abstract
The retroviral oncoprotein Tax from human T-cell leukemia virus type 1 (HTLV-1), an etiological factor that causes adult T-cell leukemia and lymphoma, has a crucial role in initiating T-lymphocyte transformation by inducing oncogenic signaling activation. We here report that Tax is a determining factor for dysregulation of autophagy in HTLV-1-transformed T cells and Tax-immortalized CD4 memory T cells. Tax facilitated autophagic process by activating inhibitor of κB (IκB) kinase (IKK) complex, which subsequently recruited an autophagy molecular complex containing Beclin1 and Bif-1 to the lipid raft microdomains. Tax engaged a crosstalk between IKK complex and autophagic molecule complex by directly interacting with both complexes, promoting assembly of LC3+ autophagosomes. Moreover, expression of lipid raft-targeted Bif-1 or Beclin1 was sufficient to induce formation of LC3+ autophagosomes, suggesting that Tax recruitment of autophagic molecules to lipid rafts is a dominant strategy to deregulate autophagy in the context of HTLV-1 transformation of T cells. Furthermore, depletion of autophagy molecules such as Beclin1 and PI3 kinase class III resulted in impaired growth of HTLV-1-transformed T cells, indicating a critical role of Tax-deregulated autophagy in promoting survival and transformation of virally infected T cells.
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Affiliation(s)
- Tong Ren
- Penn State Hershey Cancer Institute, Penn State University College of Medicine, Hershey, PA 17033
- Department of Microbiology and Immunology, Penn State University College of Medicine, Hershey, PA 17033
| | - Yoshinori Takahashi
- Department of Pharmacology, Penn State University College of Medicine, Hershey, PA 17033
| | - Xin Liu
- Penn State Hershey Cancer Institute, Penn State University College of Medicine, Hershey, PA 17033
| | - Thomas P. Loughran
- Penn State Hershey Cancer Institute, Penn State University College of Medicine, Hershey, PA 17033
| | - Shao-Cong Sun
- Department of Immunology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030
| | - Hong-Gang Wang
- Department of Pharmacology, Penn State University College of Medicine, Hershey, PA 17033
| | - Hua Cheng
- Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD 21201
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12
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Zaza G, Tomei P, Granata S, Boschiero L, Lupo A. Monoclonal antibody therapy and renal transplantation: focus on adverse effects. Toxins (Basel) 2014; 6:869-91. [PMID: 24590384 PMCID: PMC3968366 DOI: 10.3390/toxins6030869] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Revised: 02/07/2014] [Accepted: 02/21/2014] [Indexed: 02/06/2023] Open
Abstract
A series of monoclonal antibodies (mAbs) are commonly utilized in renal transplantation as induction therapy (a period of intense immunosuppression immediately before and following the implant of the allograft), to treat steroid-resistant acute rejections, to decrease the incidence and mitigate effects of delayed graft function, and to allow immunosuppressive minimization. Additionally, in the last few years, their use has been proposed for the treatment of chronic antibody-mediated rejection, a major cause of late renal allograft loss. Although the exact mechanism of immunosuppression and allograft tolerance with any of the currently used induction agents is not completely defined, the majority of these medications are targeted against specific CD proteins on the T or B cells surface (e.g., CD3, CD25, CD52). Moreover, some of them have different mechanisms of action. In particular, eculizumab, interrupting the complement pathway, is a new promising treatment tool for acute graft complications and for post-transplant hemolytic uremic syndrome. While it is clear their utility in renal transplantation, it is also unquestionable that by using these highly potent immunosuppressive agents, the body loses much of its innate ability to mount an adequate immune response, thereby increasing the risk of severe adverse effects (e.g., infections, malignancies, haematological complications). Therefore, it is extremely important for clinicians involved in renal transplantation to know the potential side effects of monoclonal antibodies in order to plan a correct therapeutic strategy minimizing/avoiding the onset and development of severe clinical complications.
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Affiliation(s)
- Gianluigi Zaza
- Renal Unit, Department of Medicine, University-Hospital of Verona, Piazzale A. Stefani 1, Verona 37126, Italy.
| | - Paola Tomei
- Renal Unit, Department of Medicine, University-Hospital of Verona, Piazzale A. Stefani 1, Verona 37126, Italy.
| | - Simona Granata
- Renal Unit, Department of Medicine, University-Hospital of Verona, Piazzale A. Stefani 1, Verona 37126, Italy.
| | - Luigino Boschiero
- First Surgical Clinic, Kidney Transplantation Center, University-Hospital of Verona, Piazzale A. Stefani 1, Verona 37126, Italy.
| | - Antonio Lupo
- Renal Unit, Department of Medicine, University-Hospital of Verona, Piazzale A. Stefani 1, Verona 37126, Italy.
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13
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Parker J, Sherman E, van de Raa M, van der Meer D, Samelson LE, Losert W. Automatic sorting of point pattern sets using Minkowski functionals. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 88:022720. [PMID: 24032877 PMCID: PMC6701179 DOI: 10.1103/physreve.88.022720] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2013] [Indexed: 06/02/2023]
Abstract
Point pattern sets arise in many different areas of physical, biological, and applied research, representing many random realizations of underlying pattern formation mechanisms. These pattern sets can be heterogeneous with respect to underlying spatial processes, which may not be visually distiguishable. This heterogeneity can be elucidated by looking at statistical measures of the patterns sets and using these measures to divide the pattern sets into distinct groups representing like spatial processes. We introduce here a numerical procedure for sorting point pattern sets into spatially homogenous groups using functional principal component analysis (FPCA) applied to the approximated Minkowski functionals of each pattern. We demonstrate that this procedure correctly sorts pattern sets into similar groups both when the patterns are drawn from similar processes and when the second-order characteristics of the pattern are identical. We highlight this routine for distinguishing the molecular patterning of fluorescently labeled cell membrane proteins, a subject of much interest in studies investigating complex spatial signaling patterns involved in the human immune response.
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Affiliation(s)
- Joshua Parker
- Department of Physics, University of Maryland, College Park, Maryland 20740, USA
| | - Eilon Sherman
- Racah Institute of Physics, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Matthias van de Raa
- Physics of Fluids Group, MESA and Institute for Nanotechnology, and J. M. Burgers Centre for Fluid Dynamics, University of Twente, The Netherlands
| | - Devaraj van der Meer
- Physics of Fluids Group, MESA and Institute for Nanotechnology, and J. M. Burgers Centre for Fluid Dynamics, University of Twente, The Netherlands
| | - Lawrence E. Samelson
- Center for Cancer Research, The National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Wolfgang Losert
- Department of Physics, University of Maryland, College Park, Maryland 20740, USA
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14
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Wilson CGM, Arkin MR. Small-molecule inhibitors of IL-2/IL-2R: lessons learned and applied. Curr Top Microbiol Immunol 2011; 348:25-59. [PMID: 20703966 DOI: 10.1007/82_2010_93] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
The IL-2:IL-2R protein-protein interaction is of central importance to both healthy and diseased immune responses, and is one of the earliest examples of successful small-molecule inhibitor discovery against this target class. Drug-like inhibitors of IL-2 have been identified through a combination of fragment discovery, structure-based design, and medicinal chemistry; this discovery approach illustrates the importance of using a diverse range of complementary screening methods and analytical tools to achieve a comprehensive understanding of molecular recognition. The IL-2 story also provides insight into the dynamic nature of protein-protein interaction surfaces, their potential druggability, and the physical and chemical properties of effective small-molecule ligands. These lessons, from IL-2 and similar discovery programs, underscore an increasing awareness of the principles governing the development of drugs for protein-protein interactions.
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Affiliation(s)
- C G M Wilson
- Small Molecule Discovery Center, University of California, San Francisco, CA 94158, USA
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15
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Scott CS, Hunt KM, Jones RA, Gignac SM, Matutes E, Drexler HG. Proliferative Hairy Cell Leukaemia (HCL-v) Resistant to Alpha-Interferon: Clinical, Diagnostic and In-Vitro Cellular Characteristics. Leuk Lymphoma 2010; 1:307-17. [DOI: 10.1080/10428199009169600] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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16
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Greene WC. An Overview of the Human Interleukin-2 Receptor: Molecular, Biochemical, and Functional Properties. Cancer Invest 2010. [DOI: 10.1080/07357908709170110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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17
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Kueng HJ, Manta C, Haiderer D, Leb VM, Schmetterer KG, Neunkirchner A, Byrne RA, Scheinecker C, Steinberger P, Seed B, Pickl WF. Fluorosomes: a convenient new reagent to detect and block multivalent and complex receptor-ligand interactions. FASEB J 2010; 24:1572-82. [PMID: 20056716 DOI: 10.1096/fj.09-137281] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
We describe for the first time fluorescent virus-like particles decorated with biologically active mono- and multisubunit immune receptors of choice and the basic application of such fluorosomes (FSs) to visualize and target immune receptor-ligand interactions. For that purpose, human embryonic kidney (HEK)-293 cells were stably transfected with Moloney murine leukemia virus (MoMLV) matrix protein (MA) GFP fusion constructs. To produce FSs, interleukins (ILs), IL-receptors (IL-Rs), and costimulatory molecules were fused to the glycosyl phosphatidyl inositol anchor acceptor sequence of CD16b and coexpressed along with MoMLV group-specific antigen-polymerase (gag-pol) in MA::GFP(+) HEK-293 cells. We show that IL-2 decorated but not control-decorated FSs specifically identify normal and malignant IL-2 receptor-positive (IL-2R(+)) lymphocytes by flow cytometry. In addition to cytokines and costimulatory molecules, FSs were also successfully decorated with the heterotrimeric IL-2Rs, allowing identification of IL-2(+) target cells. Specificity of binding was proven by complete inhibition with nonlabeled, soluble ligands. Moreover, IL-2R FSs efficiently neutralized soluble IL-2 and thus induced unresponsiveness of T cells receiving full activation stimuli via T-cell antigen receptor and CD28. FSs are technically simple, multivalent tools for assessing and blocking mono- and multisubunit immune receptor-ligand interactions with natural constituents in a plasma membrane context.
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Affiliation(s)
- Hans J Kueng
- Institute of Immunology, Center for Physiology, Pathophysiology and Immunology, Medical University of Vienna, A-1090 Borschkegasse 8A, Vienna, Austria
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18
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Delforge A, Bernier M, Bosmans E, Massy M, Bron D, Heyligen H, Raus J, Mendes Da Costa P, Stryckmans P. Measurement of Soluble Interleukin 2 Receptor in Sera of Adult Patients with Hematological or Solid Malignancies. Leuk Lymphoma 2009; 3:385-93. [DOI: 10.3109/10428199109070282] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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19
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Hoshino S, Oshimi K, Mizoguchi H. Interleukin-2 Receptor β Chain in Leukemias and Lymphomas. Leuk Lymphoma 2009. [DOI: 10.3109/10428199209064886] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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20
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Kreitman RJ. Recombinant immunotoxins containing truncated bacterial toxins for the treatment of hematologic malignancies. BioDrugs 2009; 23:1-13. [PMID: 19344187 DOI: 10.2165/00063030-200923010-00001] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Immunotoxins are molecules that contain a protein toxin and a ligand that is either an antibody or a growth factor. The ligand binds to a target cell antigen, and the target cell internalizes the immunotoxin, allowing the toxin to migrate to the cytoplasm where it can kill the cell. In the case of recombinant immunotoxins, the ligand and toxin are encoded in DNA that is then expressed in bacteria, and the purified immunotoxin contains the ligand and toxin fused together. Among the most active recombinant immunotoxins clinically tested are those that are targeted to hematologic malignancies. One agent, containing human interleukin-2 and truncated diphtheria toxin (denileukin diftitox), has been approved for use in cutaneous T-cell lymphoma, and has shown activity in other hematologic malignancies, including leukemias and lymphomas. Diphtheria toxin has also been targeted by other ligands, including granulocyte-macrophage colony-stimulating factor and interleukin-3, to target myelogenous leukemia cells. Single-chain antibodies containing variable heavy and light antibody domains have been fused to truncated Pseudomonas exotoxin to target lymphomas and lymphocytic leukemias. Recombinant immunotoxins anti-Tac(Fv)-PE38 (LMB-2), targeting CD25, and RFB4(dsFv)-PE38 (BL22, CAT-3888), targeting CD22, have each been tested in patients. Major responses have been observed after failure of standard chemotherapy. The most successful application of recombinant immunotoxins today is in hairy cell leukemia, where BL22 has induced complete remissions in most patients who were previously treated with optimal chemotherapy.
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Affiliation(s)
- Robert J Kreitman
- Clinical Immunotherapy Section, Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 9000 Rockville Pike, Bethesda, MD 20892, USA.
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UEMURA Y, TAGUCHI T, KUBOTA T, SAITO T, BANDOBASHI K, YOKOYAMA A. Neutrophil function and cytokine-specific signaling in chronic neutrophilic leukemia. Int J Lab Hematol 2009; 31:36-47. [DOI: 10.1111/j.1751-553x.2007.01000.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
Recombinant immunotoxins are proteins composed of fragments of monoclonal antibodies fused to truncated protein toxins. No agents of this class are approved yet for medical use, although a related molecule, denileukin diftitox, composed of interleukin-2 fused to truncated diphtheria toxin, is approved for relapsed/refractory cutaneous T-cell lymphoma. Recombinant immunotoxins which have been tested in patients with chemotherapy-pretreated hematologic malignancies include LMB-2 (anti-CD25), BL22 (CAT-3888, anti-CD22) and HA22 (CAT-8015, anti-CD22), each containing an Fv fragment fused to truncated Pseudomonas exotoxin. Major responses were observed with LMB-2 in adult T-cell leukemia, chronic lymphocytic leukemia (CLL), cutaneous T-cell lymphoma, Hodgkin's disease, and hairy cell leukemia (HCL). BL22 resulted in a high complete remission rate in patients with HCL, particularly those without excessive tumor burden. HA22, an improved version of BL22 with higher affinity to CD22, is now undergoing phase I testing in HCL, CLL, non-Hodgkin's lymphoma, and pediatric acute lymphoblastic leukemia.
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Affiliation(s)
- Robert J Kreitman
- Laboratory of Molecular Biology, National Cancer Institute, National Institutes of Health, 37/5124b, 9000 Rockville Pike, Bethesda, MD 20892, USA.
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23
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Singh K, Shau H, Gupta R, Kopald K, Ray P. Protein A Potentiates Lymphokine-Activated Killer Cell Induction in Normal and Melanoma Patient Lymphocytes. Immunopharmacol Immunotoxicol 2008. [DOI: 10.3109/08923979209009214] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Wang H, Zhou CL, Lei H, Zhang SD, Zheng J, Wei Q. Kaempferol: a new immunosuppressant of calcineurin. IUBMB Life 2008; 60:549-54. [PMID: 18506853 DOI: 10.1002/iub.94] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Calcineurin (CN), the Ca(2+)/calmodulin (CaM)-dependant protein phosphatase, is the target for immunosuppressive drugs cyclosporine A (CsA) and FK506. These immunosuppressants can inhibit CN activity after binding with respective immunophilins. Based on the model of screening by using p-nitrophenyl phosphate as a substrate for preliminary screening and (32)P-labeled 19-residue phosphopeptide as a specific substrate for final determination, we found Kaempferol, a natural flavonol, could inhibit CN activity in purified enzyme and Jurkat T-cells. Unlike CsA and FK506, CN inhibition by kaempferol is independent of matchmaker protein and the inhibitory manner is noncompetitive. Through investigation of inhibitions for CNA and a series of its truncated mutants, we suggested that Kaempferol could directly act on the catalytic domain. Data also indicated that the CN inhibition by kaempferol could be enhanced when the enzyme was activated in the presence of CaM and CNB. CNB is necessary for mediating inhibition of enzyme by kaempferol. The result of RT-PCR also indicated that kaempferol had an inhibitory activity against IL-2 gene expression in activated Jurkat cells. All data suggested that kaempferol could be a new immunosuppressant of CN.
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Affiliation(s)
- Hu Wang
- Department of Biochemistry and Molecular Biology, Beijing Normal University, Beijing Key Laboratory, Beijing, People's Republic of China
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25
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Brumlik MJ, Daniel BJ, Waehler R, Curiel DT, Giles FJ, Curiel TJ. Trends in immunoconjugate and ligand-receptor based targeting development for cancer therapy. Expert Opin Drug Deliv 2007; 5:87-103. [DOI: 10.1517/17425247.5.1.87] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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26
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Amato R, Menniti M, Agosti V, Boito R, Costa N, Bond HM, Barbieri V, Tagliaferri P, Venuta S, Perrotti N. IL-2 signals through Sgk1 and inhibits proliferation and apoptosis in kidney cancer cells. J Mol Med (Berl) 2007; 85:707-21. [PMID: 17571248 DOI: 10.1007/s00109-007-0205-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2007] [Revised: 03/14/2007] [Accepted: 04/16/2007] [Indexed: 10/23/2022]
Abstract
The interleukin-2 is a cytokine that is essential for lymphocytic survival and function. Ectopic expression of the IL-2 receptor in epithelial tissues has been reported previously, although the functional significance of this expression is still being investigated. We provided novel structural and functional information on the expression of the IL-2 receptor in kidney cancer cells and in other normal and neoplastic human epithelial tissues. In A-498 kidney cancer cells, we showed that IL-2 binding to its own receptor triggers a signal transduction pathway leading to the inhibition of proliferation and apoptosis. We found that the inhibition of proliferation is associated with Erk1/2 dephosphorylation, whereas the survival signals appear to be mediated by Sgk1 activation. This investigation focuses on the IL-2 induced regulation of Sgk1 and describes a role of the IL-2 receptor and Sgk1 in the regulation of epithelial tumor cell death and survival.
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Affiliation(s)
- Rosario Amato
- Department of Experimental and Clinical Medicine G. Salvatore, University Magna Graecia, Campus Biomedico, Località Germaneto, Viale Europa, Catanzaro, 88100, Italy
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27
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Abstract
Immunotoxins are proteins used to treat cancer that are composed of an antibody fragment linked to a toxin. The immunotoxin binds to a surface antigen on a cancer cell, enters the cell by endocytosis, and kills it. The most potent immunotoxins are made from bacterial and plant toxins. Refinements over many years have produced recombinant immunotoxins; these therapeutic proteins are made using protein engineering. Individual immunotoxins are designed to treat specific cancers. To date, most success has been achieved treating hematologic tumors. Obstacles to successful treatment of solid tumors include poor penetration into tumor masses and the immune response to the toxin component of the immunotoxin, which limits the number of cycles that can be given. Strategies to overcome these limitations are being pursued.
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Affiliation(s)
- Ira Pastan
- Laboratory of Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA.
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28
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Ramirez CB, Marino IR. The role of basiliximab induction therapy in organ transplantation. Expert Opin Biol Ther 2007; 7:137-48. [PMID: 17150025 DOI: 10.1517/14712598.7.1.137] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Basiliximab is a chimeric monoclonal antibody that selectively binds to the alpha-subunit (CD25) of IL-2 receptors on the surface of activated T lymphocytes, and is a highly effective prophylaxis agent against rejection in organ transplant recipients. Its pharmacokinetic profile is characterized by a biphasic and slow clearance with long terminal half-life and a volume of distribution within the central compartment and outside the circulatory system. Basiliximab induction demonstrated an excellent safety profile, with no increase in the incidence of malignancy, infections or death. It has also been used effectively in high-risk recipients, steroid-sparing and steroid-minimization protocols, and in post-transplant patients with renal dysfunction who would benefit from delayed introduction of calcineurin inhibitors. Basiliximab induction therapy given at days 0 and 4 after transplantation appears to be safe and cost-effective for immunoprophylaxis in solid organ transplant recipients, specifically in kidney and liver transplantation, when given in conjunction with dual or triple immunosuppressive therapy.
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Affiliation(s)
- Carlo B Ramirez
- Thomas Jefferson University Hospital/Jefferson Medical College, Division of Transplantation, Department of Surgery, 605 College Building, 1025 Walnut St, Philadelphia, PA 19107, USA
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Koo H, Ryu SH, Ahn HJ, Jung WK, Park YK, Kwon NH, Kim SH, Kim JM, Yoo BW, Choi SI, Davis WC, Park YH. Immunostimulatory effects of the anionic alkali mineral complex Barodon on equine lymphocytes. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2006; 13:1255-66. [PMID: 16943344 PMCID: PMC1656555 DOI: 10.1128/cvi.00150-06] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2006] [Revised: 06/14/2006] [Accepted: 08/23/2006] [Indexed: 11/20/2022]
Abstract
Previous studies have shown that the anionic alkali mineral complex BARODON has an immunoenhancing effect on pigs as an adjuvant and as a nonspecific immunostimulant. Likewise, the equine immune system has been defined with various monoclonal antibodies specific to equine leukocyte differentiation antigens to determine the possibility of enhancing equine resistance to respiratory diseases and promoting other immunostimulatory effects with the application of BARODON. Compared with the control group, after 3 weeks of treatment, BARODON-treated groups showed higher proportions of cells (P < 0.05) expressing major histocompatibility complex class II and CD2, CD4(+), CD4(+) CD25(+), CD8(+), and CD8(+) CD25(+) T lymphocytes, dendritic cells, and surface immunoglobulin M(+) B lymphocytes in peripheral blood, as well as enhanced cell proliferative responses with phytohemagglutinin and increased phagocytic activity against Streptococcus equi and Staphylococcus aureus strains with high antibiotic resistance, the bacteria frequently identified as etiologic agents of equine respiratory diseases at the Seoul Race Park in Seoul, Korea. This study shows that BARODON may act as an immunostimulator and can be an effective alternative to antimicrobial feed additives for nonspecific improvements in equine immune responses, particularly against respiratory diseases.
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Affiliation(s)
- Hyecheong Koo
- KRF Zoonotic Disease Priority Research Institute, College of Veterinary Medicine, Seoul National University, Sillim-dong, Gwanak-gu, Seoul, Republic of Korea
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30
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Abstract
Immunotoxins are proteins that contain a toxin along with an antibody or growth factor that binds specifically to target cells. Nearly all protein toxins work by enzymatically inhibiting protein synthesis. For the immunotoxin to work, it must bind to and be internalized by the target cells, and the enzymatic fragment of the toxin must translocate to the cytosol. Once in the cytosol, 1 molecule is capable of killing a cell, making immunotoxins some of the most potent killing agents. Various plant and bacterial toxins have been genetically fused or chemically conjugated to ligands that bind to cancer cells. Among the most active clinically are those that bind to hematologic tumors. At present, only 1 agent, which contains human interleukin-2 and truncated diphtheria toxin, is approved for use in cutaneous T-cell lymphoma. Another, containing an anti-CD22 Fv and truncated Pseudomonas exotoxin, has induced complete remissions in a high proportion of cases of hairy-cell leukemia. Refinement of existing immunotoxins and development of new immunotoxins are underway to improve the treatment of cancer.
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Affiliation(s)
- Robert J Kreitman
- Clinical Immunotherapy Section, Laboratory of Molecular Biology, Centers for Cancer Research, National Cancer Institute, National Institutes of Health, 9000 Rockville Pike, Building 37, Room 5124B, Bethesda, MD 20892-4255, USA.
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Annovazzi A, Bonanno E, Arca M, D'Alessandria C, Marcoccia A, Spagnoli LG, Violi F, Scopinaro F, De Toma G, Signore A. 99mTc-interleukin-2 scintigraphy for the in vivo imaging of vulnerable atherosclerotic plaques. Eur J Nucl Med Mol Imaging 2005; 33:117-26. [PMID: 16220305 DOI: 10.1007/s00259-005-1899-4] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2005] [Accepted: 07/04/2005] [Indexed: 10/25/2022]
Abstract
PURPOSE Several histopathological studies have demonstrated that vulnerable plaques are enriched in inflammatory cells. The aims of this study were: (1a) to test the ability of 99mTc-labelled interleukin-2 (99mTc-IL2) to bind to IL2R-positive (IL2R+) cells in carotid plaques and (1b) to correlate the plaque uptake of 99mTc-IL2, measured in vivo, with the number of IL2R+ cells within the plaque, measured ex vivo by histology (transversal study, TS), and (2) to evaluate changes in 99mTc-IL2 uptake in plaques, before and after treatment with a statin or a hypocholesterolaemic diet (longitudinal study, LS). METHODS Ultrasound scan was performed for plaque characterisation and localisation. Fourteen patients (16 plaques) eligible for endoarterectomy were recruited for the TS and underwent 99mTc-IL2 scintigraphy before surgery. Nine patients (13 plaques) were recruited for the LS; these patients received atorvastatin or a standard hypocholesterolaemic diet and 99mTc-IL2 scintigraphy was performed before and after 3 months of treatment. RESULTS The degree of 99mTc-IL2 uptake was expressed as the plaque/background (T/B) ratio. In patients from TS, T/B ratios correlated with the percentage of IL2R+ cells at histology (r = 0.707; p = 0.002) and the number of IL2R+ cells at flow cytometry (r = 0.711; p = 0.006). No correlations were observed between ultrasound scores and either scintigraphic or histological findings. In patients from the LS, the mean 99mTc-IL2 uptake decreased in statin-treated patients (1.75+/-0.50 vs 2.16+/-0.44; p = 0.012), while it was unchanged in the patients on the hypocholesterolaemic diet (2.33+/-0.45 vs 2.34+/-0.5). CONCLUSION 99mTc-IL2 accumulates in vulnerable carotid plaques; this accumulation is correlated with the amount of IL2R+ cells and is influenced by lipid-lowering treatment with a statin.
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Affiliation(s)
- Alessio Annovazzi
- Nuclear Medicine, 2nd Faculty of Medicine, University La Sapienza, Rome, Italy
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Kreitman RJ. Recombinant toxins in haematologic malignancies and solid tumours. Expert Opin Investig Drugs 2005; 7:1405-27. [PMID: 15992040 DOI: 10.1517/13543784.7.9.1405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Recombinant toxins constitute a new modality for the treatment of cancer, since they target cells displaying specific surface-receptors or antigens. They are fusion proteins, which contain toxin and ligand regions, and are produced in Escherichia coli. The ligand may be a growth factor or a fragment of an antibody, and the toxin is usually one of the two bacterial toxins: Pseudomonas exotoxin and diphtheria toxin. Compared to the earlier generation chemical conjugates of ligands and toxins, recombinant toxins have many advantages, including homogeneity with respect to the connection between the ligand and toxin, ease and yield of production and small size. A variety of chemotherapy-resistant haematologic and solid tumours have been targeted with recombinant toxins, and clinical trials with many of them have recently demonstrated their effectiveness. Moreover, their unwanted toxic effects are different from those of most chemotherapeutic agents, supporting the expectation that they can be combined with existing modalities to improve the clinical resources available to treat cancer in humans.
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Affiliation(s)
- R J Kreitman
- Division of Cancer Biology, National Cancer Institute, National Institutes of Health, 37/4B27, 37 Convent Drive, MSC 4255, Bethesda, MD 20892, USA
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Abstract
Recombinant immunotoxins are fusion proteins which contain a ligand derived from the immune system fused to a toxin. The protein toxin is truncated to delete its binding domain, allowing selective ligand-directed binding. Growth factor fusion toxins are often considered immunotoxins. One of these molecules, containing the truncated diphtheria toxin and human IL-2 (Ontak), Ligand Pharmaceuticals), has been approved for the treatment of cutaneous T-cell lymphoma. Recombinant immunotoxins have also been produced containing the variable domains (Fv fragment) of monoclonal antibodies fused to toxins. These agents are relatively versatile with respect to the range of antigens possible. Several of these recombinant immunotoxins have showed clinical effectiveness in Phase I testing against haematological malignancies. One of these molecules, BL22, targets CD22 on hairy-cell leukaemia and has enabled patients to achieve complete remissions despite previous treatment and resistance to chemotherapy.
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Affiliation(s)
- Robert J Kreitman
- Clinical Immunotherapy Section, Laboratory of Molecular Biology, Centers for Cancer Research, National Cancer Institute, National Institutes of Health, 9000 Rockville Pike, Building 37, Room 5124b, Bethesda, MD 20892-4255, USA.
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Kuhn DJ, Dou QP. Direct inhibition of interleukin-2 receptor ?-mediated signaling pathway induces G1 arrest and apoptosis in human head-and-neck cancer cells. J Cell Biochem 2005; 95:379-90. [PMID: 15779002 DOI: 10.1002/jcb.20446] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Overexpression of the interleukin-2 receptor (IL-2R) alpha chain in tumor cells is associated with tumor progression and a poor patient prognosis. IL-2Ralpha is responsible for the high affinity binding of the receptor to IL-2, leading to activation of several proliferative and anti-apoptotic intracellular signaling pathways. We have previously shown that human squamous cell carcinoma of a head-and-neck line (PCI-13) genetically engineered to overexpress IL-2Ralpha exhibit increased transforming activity, proliferation, and drug resistance, compared to the vector control cells (J Cell Biochem 2003;89:824-836). In this study, we report that IL-2Ralpha(+) cells express high levels of total and phosphorylated Jak3 protein and are more resistant to apoptosis induced by a Jak3 inhibitor than the control LacZ cells. Furthermore, we used daclizumab, a monoclonal antibody specific to IL-2Ralpha, and determined the effects of IL-2Ralpha inhibition on cell cycle and apoptosis as well as the involvement of potential cell cycle and apoptosis regulatory proteins. We found that daclizumab induces G(1) arrest, associated with down-regulation of cyclin A protein, preferentially in IL-2Ralpha(+) cells, but not in LacZ cells. In addition, daclizumab activates apoptotic death program via Bcl-2 down-regulation preferentially in IL-2Ralpha(+) cells. Finally, daclizumab also sensitizes IL-2Ralpha(+) cells to other apoptotic stimuli, although the effect is moderate. These results indicate that daclizumab inhibits the proliferative potential of IL-2Ralpha(+) cells via inhibition of cell cycle progression and induction of apoptosis.
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Affiliation(s)
- Deborah J Kuhn
- The Prevention Program, Barbara Ann Karmanos Cancer Institute, School of Medicine, Wayne State University, Detroit, Michigan 48201, USA
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Kaplan D. Enzymatic amplification staining for single cell analysis: applied to in situ hybridization. J Immunol Methods 2003; 283:1-7. [PMID: 14659894 DOI: 10.1016/j.jim.2003.09.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Single cell analysis by flow cytometry is a powerful modality for analyzing the expression of a set of molecules. Nevertheless, the most significant deficiency of this technology has been the poor sensitivity of flow cytometry compared to other techniques such as immunoblotting. In order to address this deficiency, we have developed an enzymatic amplification system for flow cytometry that enhances the specific signal by 10-100-fold. Using enzymatic amplification staining (EAS), we and others have been able to assess the expression of molecules that could not be detected otherwise. In this review, we show the capability of this new technology to detect specific RNA expression.
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Affiliation(s)
- David Kaplan
- Department of Pathology, Case Western Reserve University, Biomedical Research Building, Room 926, Cleveland, OH 44106-4943, USA.
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36
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Tournamille C, Filipe A, Wasniowska K, Gane P, Lisowska E, Cartron JP, Colin Y, Le Van Kim C. Structure-function analysis of the extracellular domains of the Duffy antigen/receptor for chemokines: characterization of antibody and chemokine binding sites. Br J Haematol 2003; 122:1014-23. [PMID: 12956774 DOI: 10.1046/j.1365-2141.2003.04533.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The Duffy antigen/receptor for chemokines (DARC), a seven-transmembrane glycoprotein carrying the Duffy (Fy) blood group, acts as a widely expressed promiscuous chemokine receptor. In a structure-function study, we analysed the binding of chemokines and anti-Fy monoclonal antibodies (mAbs) to K562 cells expressing 39 mutant forms of DARC with alanine substitutions spread out on the four extracellular domains (ECDs). Using synthetic peptides, we defined previously the Fy6 epitope (22-FEDVW-26), and we characterized the Fya epitope as the linear sequence 41-YGANLE-46. In agreement with these results, mutations of F22-E23, V25 and Y41, G42, N44, L45 on ECD1 abolished the binding of anti-Fy6 and anti-Fya mAbs to K562 cells respectively, Anti-Fy3 binding was abolished by D58-D59 (ECD1), R124 (ECD2), D263 and D283 (ECD4) substitutions. Mutations of C51 (ECD1), C129 (ECD2), C195 (ECD3) and C276 (ECD4 severely reduced anti-Fy3 and CXC-chemokine ligand 8 (CXCL-8) binding. CXCL-8 binding was also abrogated by mutations of F22-E23, P50 (ECD1) and D263, R267, D283 (ECD4). These results defined the Fya epitope and suggested that (1) two disulphide bridges are involved in the creation of an active chemokine binding pocket; (2) a limited number of amino acids in ECDs 1-4 participate in CXCL-8 binding; and (3) Fy3 is a conformation-dependent epitope involving all ECDs. We also showed that N-glycosylation of DARC occurred on N16SS and did not influence antibody and chemokine binding.
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Kuhn DJ, Smith DM, Pross S, Whiteside TL, Dou QP. Overexpression of interleukin-2 receptor alpha in a human squamous cell carcinoma of the head and neck cell line is associated with increased proliferation, drug resistance, and transforming ability. J Cell Biochem 2003; 89:824-36. [PMID: 12858347 DOI: 10.1002/jcb.10557] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
It has been previously demonstrated that human carcinomas express interleukin-2 receptor (IL-2R) alpha, beta, and gamma chains. The beta and gamma chains of IL-2R have intermediate binding affinity for IL-2 and are responsible for the intracellular signaling cascades after IL-2 stimulation. IL-2Ralpha lacks the cytoplasmic domain, but is essential for increasing the IL-2-binding affinity of other receptors. Overexpression of IL-2Ralpha in tumor cells is associated with tumor progression and a poor patient prognosis. To define molecular mechanisms responsible for the effects associated with IL-2Ralpha expression, ex vivo experiments were performed with the squamous cell carcinoma head-and-neck cancer line, PCI-13, which was genetically engineered to overexpress the IL-2Ralpha chain. While IL-2Ralpha-overexpressing PCI-13 cells were capable of forming colonies in soft agar, PCI-13 cells transfected with the control vector or those expressing IL-2Rgamma did not. Consistently, IL-2Ralpha-expressing tumor cells proliferated more rapidly than the control or IL-2Rgamma+ cells, associated with increased levels of cyclins A and D1 and cyclin-dependent kinase (cdk(s)) 2 and 4 proteins. In addition, IL-2Ralpha-expressing cells were significantly more resistant to apoptosis induction by a tripeptidyl proteasome inhibitor (ALLN) and two chemotherapeutic drugs (VP-16 and taxol) than the control or IL-2Rgamma+ cells. Accompanying the drug resistance, high levels of anti-apoptotic Bcl-X(L) and Bcl-2 proteins were found in the mitochondria-containing fraction of IL-2Ralpha-expressing tumor cells. Treatment of IL-2Ralpha-expressing cells with a specific Janus kinase 3 (Jak3) inhibitor decreased expression of cyclin A, cyclin D1, Bcl-X(L), and Bcl-2 proteins. Finally, high levels of ubiquitinated proteins were detected in the proliferating IL-2Ralpha-expressing cells. Our data suggest that increased proliferation rates and decreased drug sensitivity of IL-2Ralpha-expressing tumor cells are responsible for the enhanced tumor aggressiveness and poor clinical prognosis of patients whose tumors express IL-2Ralpha.
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Affiliation(s)
- Deborah J Kuhn
- Drug Discovery Program, H. Lee Moffitt Cancer Center and Research Institute, College of Medicine, University of South Florida, Tampa, Florida 33612-9497, USA
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Adu D, Cockwell P, Ives NJ, Shaw J, Wheatley K. Interleukin-2 receptor monoclonal antibodies in renal transplantation: meta-analysis of randomised trials. BMJ 2003; 326:789. [PMID: 12689974 PMCID: PMC153097 DOI: 10.1136/bmj.326.7393.789] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To study the effect of interleukin-2 receptor monoclonal antibodies on acute rejection episodes, graft loss, deaths, and rate of infection and malignancy in patients with renal transplants. DESIGN Meta-analysis of published data. DATA SOURCES Medline, Embase, and Cochrane library for years 1996-2003 plus search of medical editors' trial amnesty and contact with manufacturers of the antibodies. SELECTION OF STUDIES Randomised controlled trials comparing interleukin-2 receptor antibodies with placebo or no additional treatment in patients with renal transplants receiving ciclosporin based immunosuppression. RESULTS Eight randomised controlled trials involving 1871 patients met the selection criteria (although only 1858 patients were analysed). Interleukin-2 receptor antibodies significantly reduced the risk of acute rejection (odds ratio 0.51, 95% confidence interval 0.42 to 0.63). There were no significant differences in the rate of graft loss (0.78, 0.58 to 1.04), mortality (0.75, 0.46 to 1.23), overall incidence of infections (0.97, 0.77 to 1.24), incidence of cytomegalovirus infections (0.81, 0.62 to 1.04), or risk of malignancies at one year (0.82, 0.39 to 1.70). The different antibodies had a similar sized effect on acute rejection (test for heterogeneity P=0.7): anti-Tac (0.37, 0.16 to 0.89), BT563 (0.37, 0.1 to 1.38), basiliximab (0.56, 0.44 to 0.72), and daclizumab (0.46, 0.32 to 0.67). The reduction in acute rejections was similar for all ciclosporin based immunosuppression regimens (test for heterogeneity P=1.0). CONCLUSIONS Adding interleukin-2 receptor antibodies to ciclosporin based immunosuppression reduces episodes of acute rejection at six months by 49%. There is no evidence of an increased risk of infective complications. Longer follow up studies are needed to confirm whether interleukin-2 receptor antibodies improve long term graft and patient survival.
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Affiliation(s)
- Dwomoa Adu
- Department of Nephrology, Queen Elizabeth Hospital, Birmingham, B15 2TH.
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Signore A, Picarelli A, Annovazzi A, Britton KE, Grossman AB, Bonanno E, Maras B, Barra D, Pozzilli P. 123I-Interleukin-2: biochemical characterization and in vivo use for imaging autoimmune diseases. Nucl Med Commun 2003; 24:305-16. [PMID: 12612472 DOI: 10.1097/00006231-200303000-00011] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
We describe in detail the labelling of interleukin-2 with I ( I-IL2), its biochemical characterization, the binding assay and its use for the detection of tissues infiltrated with mononuclear cells. Human recombinant IL2 was labelled using an enzymatic method and its biochemical characterization was performed using high performance liquid chromatography (HPLC) analysis of cyanogen bromide-cleaved protein. biological and binding assays were performed on CTLL-2 cell line and on activated peripheral blood lymphocytes. studies were performed 1 h after administration of 2-3 mCi of I-IL2 in 10 newly diagnosed type 1 diabetes patients, five pre-diabetic patients, 10 Hashimoto's thyroiditis patients, 10 coeliac disease patients and 10 normal volunteers. I-IL2 scintigraphy allowed the detection and quantification of activated mononuclear cells in several affected tissues. In detail, I-IL2 accumulation was detected in the thyroid of all patients affected by Hashimoto's thyroiditis, in the bowel of all coeliac disease patients and in the pancreas of all pre-type 1 diabetic patients. By contrast, in newly diagnosed type 1 diabetics, I-IL2 scan was positive in five of the 10 studied patients. I-IL2 scintigraphy may be useful for studying autoimmune phenomena and in diagnostic protocols to evaluate the presence of other tissue involvement in patients with an organ-specific autoimmune disease.
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Affiliation(s)
- A Signore
- Dipartimento di Scienze Cliniche, Università 'La Sapienza', 00161 Rome, Italy.
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Signore A, Annovazzi A, Corsetti F, Capriotti G, Chianelli M, De Winter F, Scopinaro F. Biological imaging for the diagnosis of inflammatory conditions. BioDrugs 2003; 16:241-59. [PMID: 12196038 DOI: 10.2165/00063030-200216040-00002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Radiopharmaceuticals used for in vivo imaging of inflammatory conditions can be conveniently classified into six categories according to the different phases in which the inflammatory process develops. The trigger of an inflammatory process is a pathogenic insult (phase I) that causes activation of endothelial cells (phase II); there is then an increase of vascular permeability followed by tissue oedema (phase III). Phase IV is characterised by infiltration of polymorphonuclear cells, and a self-limiting regulatory process called apoptosis is observed (phase V). If the inflammatory process persists, late chronic inflammation takes place (phase VI). In some pathological conditions, such as organ-specific autoimmune diseases, chronic inflammation is present early in the disease. The aim of nuclear medicine in the field of inflammation/infection is to develop noninvasive tools for the in vivo detection of specific cells and tissues. This would allow early diagnosis of initial pathophysiological changes that are undetectable by clinical examination or by other diagnostic tools, and could also be used to evaluate the state of activity of the disease during therapy. These potential applications are of great interest in clinical practice. In this review, we describe the various approaches that have been developed in the last 25 years of experience. Recent advances in the diagnosis of inflammatory processes have led to the development of specific radiopharmaceuticals that are intended to allow specific stage-related diagnosis.
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Affiliation(s)
- Alberto Signore
- Department of Clinical Sciences, Nuclear Medicine, 2nd Faculty of Medicine, University of Rome, La Sapienza, Rome, Italy.
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Massenkeil G, Rackwitz S, Genvresse I, Rosen O, Dörken B, Arnold R. Basiliximab is well tolerated and effective in the treatment of steroid-refractory acute graft-versus-host disease after allogeneic stem cell transplantation. Bone Marrow Transplant 2002; 30:899-903. [PMID: 12476283 DOI: 10.1038/sj.bmt.1703737] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2002] [Accepted: 07/08/2002] [Indexed: 11/09/2022]
Abstract
Basiliximab, a chimeric interleukin-2 receptor (IL-2-R) antagonist, was evaluated in 17 patients with steroid-refractory acute graft-versus-host disease (GVHD) after allogeneic stem cell transplantation (SCT). Patients were transplanted from a related (n = 6) or unrelated (n = 11) HLA-identical donor because of acute lymphoblastic leukemia (n = 4), acute myeloid leukemia (n = 3), chronic myeloid leukemia (n = 7), myelodysplastic syndrome (n = 1), non-Hodgkin's lymphoma (n = 1), and multiple myeloma (n = 1). Basiliximab was given at a dose of 2 x 20 mg on 2 consecutive days after steroid-refractory acute GVHD had developed. Basiliximab was repeated on day 8 in cases of persistent GVHD. A median of four basiliximab infusions (range 1-12) were given to these patients. None had infusion-associated or cytokine-related side-effects after basiliximab. Twelve of 17 patients (71%) responded to basiliximab, 9/17 (53%) had a complete response (CR) of acute GVHD and 3/17 (18%) had a partial response (PR). Five of 17 patients (29%) did not respond. Chronic GVHD developed in 8/13 evaluable patients and only 2/8 had responded to basiliximab before. Five of 13 evaluable patients have no signs of chronic GVHD and all five had a CR or PR after basiliximab. This is the first report on the safety of basiliximab in patients with steroid-refractory acute GVHD. Our data suggest that basiliximab is effective in a substantial proportion of these patients.
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Affiliation(s)
- G Massenkeil
- Dept. of Internal Medicine, Division of Hematology and Oncology, University Hospital Charité, Campus Virchow-Klinikum, Humboldt-University, Berlin, Germany
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Valles S, Caunt CJ, Walker MH, Qwarnstrom EE. PDGF enhancement of IL-1 receptor levels in smooth muscle cells involves induction of an attachment-regulated, heparan sulfate binding site (IL-1RIII). J Transl Med 2002; 82:855-62. [PMID: 12118087 DOI: 10.1097/01.lab.0000020420.07575.3f] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
This study shows that increase in IL-1 receptor levels by platelet derived growth factor (PDGF) involves an enhancement of a matrix-dependent, low-affinity receptor that constitutes a heparan sulfate. Fibronectin attachment caused pronounced alterations in IL-1 receptor function in smooth muscle cells, involving a pronounced increase in cell surface binding from an average of 2,000 up to approximately 8,000 receptors/cell and an increase in affinity (K(a)) of the type I receptor from 1.8 +/- 0.9 x 10(9) to 3.7 +/- 0.5 x 10(9) M(-1). PDGF stimulation similarly enhanced the level of cell surface binding by between 30% and 100%, with, in general, less effect on cells plated on fibronectin. Further, PDGF had a pronounced effect on the type I receptor affinity in the absence of matrix attachment, increasing the K(a) from 1.77 +/- 0.93 x 10(9) to 5.1 +/- 2.1 x 10(9) M(-1). Scatchard analyses revealed that PDGF, similarly to fibronectin attachment, caused enhancement of a second low-affinity binding site. Antibody blocking showed that approximately 50% of the attachment-induced increase was independent of type I receptor binding. Further, a similar fraction of the cell surface interaction was blocked by soluble heparan sulfate and dependent on cell binding to the heparan binding site. Cross-linking demonstrated that, in addition to the type I receptor, IL-1 bound to a second high molecular weight complex of 300 kd, induced by fibronectin attachment as well as by PDGF in the absence of matrix. Biochemical analyses demonstrated that this second site constitutes a heparan sulfate, which directly interacted with the type I receptor after recruitment to the complex, and which bound up to 50% and 25% of the ligand after fibronectin attachment and PDGF stimulation, respectively. The data show that PDGF induces an attachment-regulated low-affinity IL-1 binding site in smooth muscle cells, constituting a heparan sulfate. Correlation of the recruitment of this component to the IL-1 receptor complex with structural regulation of receptor function and enhancement of IL-1-mediated responses suggests that this is a significant mechanism in PDGF augmentation of local inflammatory responses during vessel wall pathogenesis.
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Affiliation(s)
- Soraya Valles
- Cell Biology Unit, Division of Genomic Medicine, University of Sheffield, Sheffield, United Kingdom
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Lundin K, Blomberg K, Nordström T, Lindqvist C. Development of a time-resolved fluorescence resonance energy transfer assay (cell TR-FRET) for protein detection on intact cells. Anal Biochem 2001; 299:92-7. [PMID: 11726189 DOI: 10.1006/abio.2001.5370] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
An assay named Cell TR-FRET based on time-resolved fluorescence resonance energy transfer, here utilized for detection of receptor proteins on intact cells, is described. In this assay, intact membrane-biotinylated Sf9 cells expressing human interleukin-2Ralpha due to infection with a recombinant baculovirus were prelabeled with a streptavidin-europium (Eu(3+)) chelate, the donor. These prelabeled cells were used in a homogeneous assay by addition of a fluorochrome-labeled anti-hIL-2Ralpha-specific antibody, 7G7B6-Cy5, the acceptor. Binding of 7G7B6-Cy5 to hIL-2Ralpha expressed on the cell surface and europium-labeled streptavidin to surface biotin esters brings the donor and the acceptor in close proximity, allowing transfer of energy from the excited state donor to the acceptor. This energy transfer was specifically inhibited by unlabeled antibody and by free biotin. The described assay constitutes a general method since no specific component of the cell membrane is labeled, thereby allowing a number of binding studies on the cell membrane, including receptor density determinations, to be performed. In addition, due to the rapid fashion in which the Cell TR-FRET assay is accomplished, it can be a valuable method not only for identifying novel membrane-associated proteins, but also for drug screening of large samples in high-throughput format.
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Affiliation(s)
- K Lundin
- Department of Biology, Abo Akademi University, FIN-20520 Turku, Finland
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44
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Affiliation(s)
- B Nashan
- Klinik fuer Viszeral- und Transplantationschirurgie, Medizinische Hochschule Hannover, Hannover, Germany
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45
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Horuk R, Shurey S, Ng HP, May K, Bauman JG, Islam I, Ghannam A, Buckman B, Wei GP, Xu W, Liang M, Rosser M, Dunning L, Hesselgesser J, Snider RM, Morrissey MM, Perez HD, Green C. CCR1-specific non-peptide antagonist: efficacy in a rabbit allograft rejection model. Immunol Lett 2001; 76:193-201. [PMID: 11306147 DOI: 10.1016/s0165-2478(01)00172-9] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The classic signs of acute cellular rejection during organ transplantation include the infiltration of mononuclear cells into the interstitium. This recruitment of leukocytes into the transplanted tissue is promoted by chemokines like RANTES. Since RANTES is a potent agonist for the CC chemokine receptor CCR1, we examined whether the CCR1 antagonist BX 471 was efficacious in a rabbit kidney transplant rejection model. BX 471 was able to compete with high affinity with the CCR1 ligands MIP-1alpha and RANTES for binding to HEK 293 cells expressing rabbit CCR1. BX 471 was a competitive antagonist of rabbit CCR1 in Ca(2+) flux studies. Two separate studies in which animals were subcutaneously implanted with slow release pellets of BX 471 demonstrated that animals implanted with BX 471 had increased survival compared with untreated controls or animals implanted with placebo. The mean survival time for the placebo group was 12.33+/-1.7 days. The animals in the BX 471 treated group had mean survival times of 16.9+/-2.1 and 16.0+/-1.7 days, respectively, for the two studies. Analysis of the combined data by Student t-test gave a P value of 0.03 that is significant at the 0.05 level. In addition, there was a marked reduction in the urea and creatinine levels in the BX 471 treated animals compared with the control and placebo groups in both studies. Finally, pathologic analysis of the kidneys in the rabbit renal transplantation model from animals in the different groups showed that BX 471 was similar to cyclosporin in its ability to prevent extensive infarction of transplanted kidneys. Based on the data from these studies, BX 471 shows clear efficacy at the single dose tested compared with animals treated with placebo.
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Affiliation(s)
- R Horuk
- Department of Immunology, Berlex Biosciences, 15049 San Pablo Avenue, Richmond, CA 94806, USA.
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Azenabor AA, Hoffman-Goetz L. 17 beta-estradiol increases Ca(2+) influx and down regulates interleukin-2 receptor in mouse thymocytes. Biochem Biophys Res Commun 2001; 281:277-81. [PMID: 11181041 DOI: 10.1006/bbrc.2001.4341] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The influx of Ca(2+) across the T lymphocyte membrane is an essential triggering signal for activation and proliferation by an antigen. The aim of this study was to determine if Ca(2+) influx through estradiol receptor (ER) operated channels of Ca(2+) entry induced activation of lymphoid cells. Mouse thymocytes were incubated with 17 beta-estradiol (E) and in the presence or absence of the mitogen, phytohemagglutinin (PHA). Despite evidence of an enhanced binding of E to ER on thymocyte membranes, and an E dose-related influx of Ca(2+), there was a consistent down regulation of IL-2 receptor expression (P < 0.001). Incubation of thymocytes with PHA enhanced IL-2 receptor expression although the down regulatory effect of E was still evident. The results suggest that the Ca(2+) channel activated by E may have a down regulatory effect on the IL-2 receptor in thymus cells leading to the dampening of cell activation process.
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Affiliation(s)
- A A Azenabor
- Department of Health Studies and Gerontology, University of Waterloo, Waterloo, Ontario, Canada
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47
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Signore A, Procaccini E, Annovazzi A, Chianelli M, van der Laken C, Mire-Sluis A. The developing role of cytokines for imaging inflammation and infection. Cytokine 2000; 12:1445-54. [PMID: 11023659 DOI: 10.1006/cyto.2000.0746] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The diagnosis of inflammatory processes is an important goal in medicine. In some cases the diagnosis is easy, based on the clinical history and the physical examination of the patient. Other cases are more difficult to diagnose because they are asymptomatic or with non-specific symptoms. Thus, several imaging techniques have been developed for the diagnosis of inflammatory processes, from the simple X-ray to the more sophisticated computerised tomography, magnetic resonance imaging and nuclear medicine scan. They provide different information and their role in different diseases will be discussed in this review with particular emphasis on the expanding field of the use of radiolabelled cytokines for imaging infection/inflammation. So far, IL-1, IL-1ra, IL-2, IL-6, IL-8, IL-10, IL-12 p40, G-CSF, IFN-gamma and EGF have been radiolabelled for in vivo targetting of different leukocyte subsets with promising results for their clinical use.
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Affiliation(s)
- A Signore
- Nu.M.E.D. Group, Servizio Speciale di Medicina Nucleare, Department of Clinical Sciences, University of Rome 'La Sapienza', Rome, Italy.
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Decker T, Schneller F, Kronschnabl M, Dechow T, Lipford GB, Wagner H, Peschel C. Immunostimulatory CpG-oligonucleotides induce functional high affinity IL-2 receptors on B-CLL cells: costimulation with IL-2 results in a highly immunogenic phenotype. Exp Hematol 2000; 28:558-68. [PMID: 10812246 DOI: 10.1016/s0301-472x(00)00144-2] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
OBJECTIVE CpG-oligodeoxynucleotides (CpG-ODN) have been shown to induce proliferation, cytokine production, and surface molecule regulation in normal and malignant human B cells. In the present study, we investigated the potential of CpG-ODN to induce functional high-affinity receptors in leukemic and normal B cells and the effects of costimulation with IL-2 on proliferation, cytokine secretion, and surface molecule regulation. METHODS Highly purified B cells from B-CLL patients and normal controls were stimulated with CpG-ODN with or without IL-2. Expression of CD25 was determined using FACS, and the presence of high-affinity IL-2 receptors was determined by scatchard analysis. Costimulatory effects of IL-2 and CpG-ODN were investigated using proliferation assays, ELISA (IL-6, TNF-alpha), and FACS analysis (CD80, CD86 expression). Reactivity of autologous and allogeneic T cells toward activated B-CLL cells was determined in mixed lymphocyte reactions and Interferon-gamma Elispot assays. RESULTS The CpG-ODN DSP30 caused a significantly stronger induction of the IL-2 receptor alpha chain in malignant as compared with normal B cells (p = 0.03). This resulted in the expression of functional high-affinity IL-2 receptors in B-CLL cells, but fewer numbers of receptors with less affinity were expressed in normal B cells. Although addition of IL-2 to CpG-ODN-stimulated cells augmented proliferation in both normal B cells and B-CLL cells, no costimulatory effect on cytokine production or surface molecule expression could be observed in normal B cells. In contrast, TNF-alpha and IL-6 production was increased in B-CLL cells, and the expression of CD80 and CD86 was further enhanced when IL-2 was used as a costimulus. Autologous and allogeneic immune recognition of B-CLL cells stimulated with CpG-ODN and IL-2 was increased compared with B-CLL cells stimulated with CpG-ODN alone. CONCLUSION Stimulation of B-CLL cells with CpG-ODN and IL-2 might be an attractive strategy for potential immunotherapies for B-CLL patients.
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MESH Headings
- Adjuvants, Immunologic/pharmacology
- Antigens, CD/genetics
- B-Lymphocytes/drug effects
- B-Lymphocytes/immunology
- B7-1 Antigen/genetics
- B7-2 Antigen
- Flow Cytometry
- Gene Expression Regulation/drug effects
- Gene Expression Regulation/immunology
- Humans
- Interleukin-2/pharmacology
- Interleukin-6/genetics
- Kinetics
- Leukemia, Lymphocytic, Chronic, B-Cell/blood
- Leukemia, Lymphocytic, Chronic, B-Cell/immunology
- Leukemia, Lymphocytic, Chronic, B-Cell/pathology
- Membrane Glycoproteins/genetics
- Oligodeoxyribonucleotides
- Oligonucleotides/pharmacology
- Receptors, Interleukin-2/genetics
- Reference Values
- Tumor Cells, Cultured
- Tumor Necrosis Factor-alpha/genetics
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Affiliation(s)
- T Decker
- IIIrd Department of Medicine and, Technical University of Munich, Munich, Germany
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Ehrhardt RO, Lúdvíksson BR. When immunization leads to autoimmunity: chronic inflammation as a result of thymic and mucosal dysregulation in IL-2 knock-out mice. Int Rev Immunol 2000; 18:591-612. [PMID: 10672503 DOI: 10.3109/08830189909088500] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- R O Ehrhardt
- Protein Design Labs, Inc., Fremont, CA 94555, USA.
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Yazdanbakhsh K, Rios M, Storry JR, Kosower N, Parasol N, Chaudhuri A, Reid ME. Molecular mechanisms that lead to reduced expression of duffy antigens. Transfusion 2000; 40:310-20. [PMID: 10738032 DOI: 10.1046/j.1537-2995.2000.40030310.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND In the Duffy blood group system, the null phenotype Fy(a-b-) has been classically associated with a mutated GATA box, while the Fy(x) phenotype weak Fy(b) is associated with Arg89Cys and Ala100Thr mutations. This report assesses the prevalence of the Duffy GATA box and the Fy(x)-associated mutations in white and African American (black) donors and investigates the molecular mechanism underlying the Fy(x) phenotype. STUDY DESIGN AND METHODS PCR RFLP Duffy genotyping was performed on blood samples from blacks and whites. Duffy antigen expression (Fy(a), Fy(b), Fy6, Fy3) on RBCs was measured by flow cytometry. By site-directed mutagenesis, the relevance of each Fy(x)-associated mutation to Duffy (mRNA, antigen, and protein) expression was analyzed in transfectants by Northern blotting, flow cytometry, and immunoblotting. RESULTS The mutated GATA box occurred at a high allele frequency (0.8) in blacks and was rare among whites. Conversely, the Fy(x)-associated mutations were absent in blacks, but present in 3.5 percent of whites. By flow cytometry, Duffy antigens (Fy(a) or Fy(b), Fy6 and Fy3) showed a dosage effect in RBC samples that were transcriptionally silenced by the GATA box mutation in one allele. By contrast, the reduced (10%) Duffy protein in Fy(x) RBCs was shown by heterologous expression analysis not to be due to reduced RNA levels, but to protein instability caused by Arg89Cys. CONCLUSIONS Reduced Duffy expression can result from mutations affecting transcription (mutated GATA box in one allele) or instability of the translated protein (Arg89Cys). The frequencies of these mutations vary among populations.
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