Developmental relationship between mesenchymal stem/progenitor cells and hematopoietic cells during human embryogenesis

Abstract

Objective To analyze the developmental relationship between mesenchymal stem/progenitor cells (MSPCs) and hematopoietic cells during human embryogenesis. Methods Aborted embryos at different developmental stages were used in this study after medical abortion. Embryonic blood tissues were isolated and digested into single cells. These single cells were plated in semisolid medium in favor of the differentiation of colony-forming cell with high proliferative potential (HPP-CFC) and incubated for 10 to 14 d. Individual colonies with diameter more than 0.5 mm were picked and replated in liquid medium. Fibroblastic adherent cells appeared in the replated colonies were cultured for cell proliferation and cytokins expressed on cell surface were identified to analyze whether they had the characteristics of MSPCs. Results This study summarized the dynamic development of HPP-CFCs and other hematopoietic progenitor cells in different tissues including aorta-gonad-mesonephros (AGM) region, yolk sac and embryonic liver. From the 28-somite stage, a proportion of HPP-CFCs in AGM region could give rise to adherent fibroblastic cells in addition to hematopoietic cells. The adherent cells harbored the differentiation potential of MSPCs and could inhibit the proliferation of T cells in lymphocyte transformation test. Conclusions This study suggests some prehematopoietic precursors in AGM region can give rise to both hematopoietic progenitors and MSPCs during human embryogenesis. Key words: Mesenchymal stem cell/progenitor cells; Colony-forming cell with high proliferative potential; Hematopoietic cells; Immunosuppression; Lymphocyte transformation test