Original Article
Copyright ©2011 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Stem Cells. Jun 26, 2011; 3(6): 53-62
Published online Jun 26, 2011. doi: 10.4252/wjsc.v3.i6.53
Short and long term fate of human AMSC subcutaneously injected in mice
Pilar López-Iglesias, Alejandro Blázquez-Martínez, Jorge Fernández-Delgado, Javier Regadera, Manuel Nistal, Maria P De Miguel
Pilar López-Iglesias, Alejandro Blázquez-Martínez, Maria P De Miguel, Cell Engineering Laboratory, IdiPaz, La Paz Hospital Research Institute, Madrid 28046, Spain
Jorge Fernández-Delgado, Department of Plastic Surgery and Center for Comprehensive Breast Treatment, Santa Cristina Hospital, Madrid 28001, Spain
Javier Regadera, Department of Histology and Neuroscience, Autonomous University of Madrid 28046, Spain
Manuel Nistal, Department of Pathology, La Paz Hospital, Madrid 28046, Spain
Author contributions: López-Iglesias P and Blázquez-Martínez A performed the majority of experiments and were involved in the manuscript writing; Fernández-Delgado J provided all the human materials; Regadera J and Nistal M provided vital reagents and were also involved in editing the manuscript; De Miguel MP designed the study, provided financial support and wrote the manuscript.
Supported by Project grants SAF2008-03837 and SAF2010-19230 from Ministry of Science and Innovation, and Agencia Laín Entralgo, Madrid, Spain, and from BioMedical Foundation Mutua Madrileña, Spain
Correspondence to: Maria P De Miguel, PhD, Cell Engineering Laboratory, IdiPAZ, La Paz Hospital, Edificio Maternidad planta 1, Paseo Castellana 261, Madrid 28046, Spain. mariapdemiguel@gmail.com
Telephone: +34-91-2071458 Fax: +34-91-7277050
Received: September 13, 2010
Revised: January 15, 2011
Accepted: January 22, 2011
Published online: June 26, 2011

AIM: To study the ability of human adipose-derived mesenchymal stem cells (AMSCs) to survive over the short and long term, their biodistribution and their biosafety in vivo in tumor-prone environments.

METHODS: We subcutaneously injected human AMSCs from different human donors into immunodeficient SCID mice over both short- (2 and 4 mo) and long- (17 mo) term in young, and aged tumor-prone mice. Presence of human cells was studied by immunohistochemistry and polymerase chain reaction analysis in all organs of injected mice.

RESULTS: Subcutaneously injected AMSCs did not form teratomas at any time point. They did not migrate but remained at the site of injection regardless of animal age, and did not fuse with host cells in any organ examined. AMSCs survived in vivo for at least 17 mo after injection, and differentiated into fibroblasts of the subdermic connective tissue and into mature adipocytes of fat tissue, exclusively at the site of injection.

CONCLUSION: Our results support the assertion that AMSC may be safe candidates for therapy when injected subcutaneously because of their long term inability to form teratomas.

Keywords: Adipose-derived stem cells, Cell transplant, SCID mice, Teratoma, Mesenchymal stem cells, Cell therapy, Biosafety