胎肝条件培养液体外诱导人骨髓间充质干细胞定向分化为造血细胞的研究

目的：探讨人骨髓间充质干细胞（hMSCs）体外造血分化潜能。方法： 选用孕12.5-14.5 d（12.5-14.5 dpc）的昆明小鼠，分别制备小鼠胎肝基质细胞条件培养液（FLSC-CM）及胚胎成纤维细胞饲养层（FD），将体外扩增的CD34-CD45-hMSCs分别接种于含FLSC-CM、FD和IL-6及SCF组合的培养体系中，培养7 d后，通过形态学、表型、粒-单/巨噬细胞系集落培养（CFU-GM）对分化细胞进行鉴定。结果： hMSCs与FLSC-CM共培养组产生的非贴壁细胞明显增多，形态类似于单核或小淋巴细胞，部分细胞可表达人造血细胞特异性表面分子（CD34和CD45），在含人粒-单集落刺激因子（GM-CSF）的甲基纤维素培养体系中能够形成CFU-GM，而FD和IL-6+SCF诱导组无上述作用。结论： FLSC-CM可诱导CD34-CD45-hMSCs分化为造血细胞，提示hMSCs具有体外造血分化潜能。

Potential of human bone marrow mesenchymal stem cells differentiating into hematopoietic cells with fetal liver stromal cell-conditioned medium in vitro

AIM: To explore the potential of human bone marrow mesenchymal stem cells (hMSCs) differentiating into hematopoietic cells with murine fetal liver stromal cell-conditioned medium (FLSC-CM) in vitro. METHODS: 12.5-14.5 days post coitus (dpc ) of KM mice were used for the preparation of fetal liver stromal cell-conditioned medium (FLSC-CM) and embryonic fibroblast feeder layer (FD). Culture-expanded hMSCs were directly contacted with FLSC-CM, FD, and the combination of human interleukin-6 (IL-6) or stem cell factor (SCF), respectively. Seven days later, the non-adherent cells were collected and characterized by morphology, immunophenotypes, and colony forming unit-granulocyte/macrophage culture assay. RESULTS: The number of nonadherent cells derived from hMSCs cultured with FLSC-CM was increased remarkably than those with either FD or cytokines. The non-adhered cells with the morphology of monocyte-or small lymphocyte-like cells were positive for human CD34, CD45 and had the capacity to form the hematopoietic progenitor colonies in methylcellulose cultures containing recombined human granulocyte/macrophage-colony stimulating factor (rhGM-CSF). CONCLUSION: hMSCs were successfully induced toward their differentiation into CD34 CD45 hematopoietic progenitors after being cultivated with FLSC-CM. This study suggests that hMSCs have the hematopoietic differentiation potential in vitro.