人胎盘源贴壁细胞支持脐血CD34+细胞体外扩增

从胎盘中分离培养人胎盘源贴壁细胞 (humanplacentaderivedadherentcells,hPDAC) ,研究其对脐血CD34+细胞体外扩增作用。以酶消化法自人胎盘组织中分离培养hPDAC ,并以流式细胞术对其进行鉴定。进一步 ,采用免疫磁珠法分离人脐血CD34+细胞 ,建立以hPDAC为滋养层的CD34+细胞体外扩增培养体系 ,并与无滋养层的液体培养体系相比 ,观察不同培养体系对有核细胞总数、CFC及CD34+细胞百分率的影响。结果表明 ,人胎盘组织中可分离培养出hPDAC ,并证实其为混合性细胞群体 ,主要含有间充质细胞。以hPDAC为滋养层的共培养体系较无滋养层液体培养体系对有核细胞总数、CFC及CD34+细胞均具有明显的扩增效应 ,其中以SCF +IL 3+IL 6 +FL +hPDAC组扩增效果最强 ,分别扩增了 ( 12 6 .0± 6 .7)倍 ,( 4 9.8± 1.7)倍和 ( 8.3± 1.6 5 )倍。上述结果提示 ,hPDAC具有体外支持造血作用 ,并提供了一与脐血CD34+细胞体外扩增相适应的新滋养层。

Human Placenta Derived Adherent Cells Support in vitro Expansion of Umbilical Cord Blood CD34+Cells

The objective of this study was to elucidate the effect of human placenta adherent cells (hPDAC) on expansion of human umbilical cord blood CD34(+) cells in vitro. hPDAC was isolated and characterized in human placenta tissue by using enzyme-digesting method and flow cytometry. A co-culture system was established with hPDAC and cord blood CD34(+) cells. The CD34(+) cells were cultured in different culture systems with different combinations of hPDAC and SCF, IL-3, IL-6 and FL. The number of total nucleated cells, CFC and CD34(+) cells were repeatedly counted in culture for 4 weeks. The results showed that the hPDAC displayed fibroblast-like morphology, and were positive for CD29, CD44, CD166, HLA-ABC and UEA-1, and negative for CD34, CD45 and HLA-DR. Functionally, ex vivo expansion of CD34(+) cells on feeder layer of placental adherent cells was significantly higher than that no feeder layer group. SCF + IL-3 + IL-6 + FL + hPDAC manifested the most potent combination, with the number of total nucleated cells increasing by (126.0 +/- 6.7)-fold, progenitor cells (CFC) (49.8 +/- 1.7)-fold and CD34(+) cells (8.3 +/- 1.65)-fold. It is concluded that placental adherent cells could support hematopoiesis in vitro and work as a suitable feeder layer for cord blood stem/progenitor cell expansion.