人胎盘与脐动、静脉血造血干/祖细胞归巢相关黏附分子表达的研究

为了评价人胎盘组织造血干/祖细胞(hematopoieticstem/progenitorcell,HSPC)的归巢能力,采用机械法制备人胎盘组织单个细胞悬液,用流式细胞术分析胎盘组织及脐动、静脉血有核细胞中CD34+细胞及其亚群的含量,检测三者来源的CD34+细胞表面归巢相关黏附分子CD44、CD11a、CD62L、CD49d、CD49e和CD54的表达水平。结果显示,胎盘组织CD34+细胞及CD34+CD38-细胞百分率明显高于脐动、静脉血;脐动脉与脐静脉血中HSPC百分率没有明显差异。胎盘来源CD34+细胞高度表达黏附分子CD11a、CD49d、CD44、CD49e及CD54,其中表达CD49e及CD54水平明显高于脐动、静脉血CD34+细胞。胎盘来源的CD34+CD62L+细胞百分率为(64.58±15.52)%,低于脐静脉血来源的表达。结论:人胎盘富含HSPC。胎盘来源的CD34+细胞多数黏附分子的表达水平近似或高于脐血,提示胎盘HSPC的归巢能力有可能强于脐带血。

Expressions of Homing-Related Adhesion Molecules in Hematopoietic Stem/Progenitor Cells Derived from Human Placenta, Umbilical Cord Arterial and Venous Blood

The aim of this study was to evaluate the homing capabilities of hematopoietic stem/progenitor cells (HSPCs) derived from human placenta tissues (PT). Single cell suspension of human PT was prepared by mechanical method. The expression levels of homing-related adhesion molecules (HRAM) including CD11a, CD49d, CD44, CD49e, CD62L and CD54 on CD34~+ cells and the percentages of CD34~+ cells and their subpopulations in nucleated cells (NC) from fresh human PT , umbilical cord arterial blood (UCAB) and umbilical cord venous blood(UCVB) were detected by using flow cytometry. The results showed that the percentage of CD34~+cells and CD34~+CD38~- cells in placenta were higher than those in UCAB and UCVB. There were no significant difference in percentage of HSPC between UCAB and UCVB. Placenta-derived CD34~+ cells strongly expressed CD11a, CD49d, CD44, CD49e and CD54, among which expression levels of CD49e and CD54 on placenta-derived CD34~+ cells were significantly higher than those on UCAB and UCVB-derived CD34~+ cells. While the percentage of CD34~+CD62L~+ cells in placenta was only lower than that in UCVB. It is concluded that human placenta is rich in HSPC. Moreover, the expression levels of most HRAM in CD34~+ cells from PT are higher than those from UCAB and UCVB or are close to them. It suggested that HSPCs derived from PT might have stronger homing capabilities than those from UCB.