Studies on differentiation potential of human bone marrow mesenchymal stem cells into hematopoietic cells in vivo / 中国病理生理杂志

ABSTRACT

AIM: To investigate the differentiation potential of human bone marrow mesenchymal stem cells (hBMMSCs) into hematopoietic cells in vivo. METHODS: hBMMSCs prepared from the bone marrow-aspirate sample obtained from healthy human donors were culture-expanded in vitro with 5-8 passages. hBMMSCs(P5-8, 4.8?10 5 cells/mouse) were injected into the severe combined immuodeficiency (SCID) mice treated by cyclophosphamide(CPA) and various tissues were analyzed at 35 days post-transplant for the presence of differentiated human cells. RESULTS: hBMMSCs(P5-8) viability, which was determined by typan blue staining at the end of the harvest and before infusion, was greater than 95% in every infusate at both time points. Cells characterized by flow cytometry using human MSC-specific monoclonal antibodies were uniformly positive for CD29, CD44, CD90, CD105, CD106, CD166 and negative for CD11a, CD14, CD34, CD38, CD45, CD80, CD86 which are common on cells of the hematopoietic lineages. Analysis of PB demonstrated that 5 of 6 hBMMSCs transplanted SCID mice had low level of circulating human CD45 +/ H-2D d- cells(range from 0.17% to 0.36%)and CD34 +/ H-2D d- cells(range from 0.10% to 0.50%). Analysis of BM for the presence of hematopoietic chimerism demonstrated human CD45 +/ H-2D d- cells and CD34 +/ H-2D d- cells in the marrow of 4 out of 6 hBMMSCs transplanted SCID mice (0.10%-0.19% and 0.03%-0.52%, respectively). Human hematopoietic cells with these same phenotype were also detected in the spleen 4 of the hBMMSCs transplanted SCID mice (range from 0.19% to 1.65% ,from 0.20% to 0.26%, respectively). No human hematopoietic cell was seen either in the PB, BM or spleen of all control animals. CONCLUSION: hBMMSCs have the ability to differentiate into blood cells of multiple lineages, including CD34 + hematopoietic stem cells/progenitor cells (HSC/HPC).