Basic Research
Copyright ©2006 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Jan 21, 2006; 12(3): 393-402
Published online Jan 21, 2006. doi: 10.3748/wjg.v12.i3.393
Cocultivation of umbilical cord blood CD34+ cells with retro-transduced hMSCs leads to effective amplification of long-term culture-initiating cells
Chun-Gang Xie, Jin-Fu Wang, Ying Xiang, Li-Yan Qiu, Bing-Bing Jia, Li-Juan Wang, Guo-Zhong Wang, Guo-Ping Huang
Chun-Gang Xie, Jin-Fu Wang, Ying Xiang, Li-Yan Qiu, Bing-Bing Jia, Li-Juan Wang, Guo-Zhong Wang, Guo-Ping Huang, College of Life Sciences, Zhejiang University, Hangzhou 310012, Zhejiang Province, China
Chun-Gang Xie, Institute of Life Science, Jiangsu University, Zhenjiang 212013 , Jiangsu Province, China
Supported by the grants of NIH-Heart, Lung & Blood, No. IR014L70593-01 and Zhejiang Scientific Foundation, No. 2003C23015
Correspondence to: Professor Jin-Fu Wang, College of Life Sciences, Zhejiang University, 232 Wen San Road, Hangzhou 310012, Zhejiang Province, China. wjfu@zju.edu.cn
Telephone: +86-571-87585600 Fax: +86-571-85128776
Received: April 22, 2005
Revised: May 8, 2005
Accepted: May 13, 2005
Published online: January 21, 2006
Abstract

AIM: To establish a novel coculture system for ex vivo expansion of umbilical cord blood(UCB) hematopoietic progenitors using thrombopoietin (TPO)/Flt-3 ligand (FL)-transduced human marrow-derived mesenchymal stem cells (tfhMSCs) as feeder.

METHODS: UCB CD34+ cells were isolated and cultured using four culture systems in serum-containing or serum-free medium. Suitable aliquots of cultured cells were used to monitor cell production, clonogenic activity, and long-term culture-initiating culture (LTC-IC) output. Finally, the severe-combined immunodeficient (SCID) mouse-repopulating cell (SRC) assay was performed to confirm ability of the cultured cells to reconstitute long-term hematopoiesis.

RESULTS: There were no significant differences in the number of total nucleated cells among different culture systems in serum-containing medium during 21-d culture. However, on d 14, the outputs of CD34+ cells, CFU-C and CFU-GEMM in tfhMSCs coculture system were significantly enhanced. LTC-IC assay demonstrated that the tfhMSCs coculture system had the most powerful activity. The severe-combined immunodeficient (SCID) mouse repopulating cell (SRC) assay confirmed extensive ability of the expanded cells to reconstitute long-term hematopoiesis. Furthermore, PCR analysis demonstrated the presence of human hematopoietic cells in the bone marrow and peripheral blood cells of NOD/SCID mice.

CONCLUSION: The TPO/FL-transduced hMSCs, in combination with additive cytokines, can effectively expand hematopoietic progenitors from UCB in vitro and the tfhMSCs coculture system may be a suitable system for ex vivo manipulation of primitive progenitor cells under contact culture conditions.

Keywords: Mesenchymal stem cells; Thrombopoietin; Flt-3 ligand; Hematopoiesis