细胞表面黏附分子在造血干细胞动员中的作用机制

目的　研究粒系集落刺激因子 (G CSF)进行干细胞动员时干细胞表面黏附分子的变化 ,从黏附分子角度说明G CSF的动员机制。方法　将重组人G CSF(惠尔血 )或生理盐水注射于小鼠皮下 ,每日两次 ,连续 7d ,收集G CSF使用前后骨髓和外周血单个核细胞 ,计数外周血Sca 1 干细胞数目和骨髓有核细胞数 ,同时分别检测细胞表面CD49d、CD44的表达和干细胞与骨髓基质蛋白黏附能力的变化。结果　重组人G CSF对小鼠有和人类相似的动员作用 ,使用G CSF 7d后外周血Sca 1 细胞数增高近 2倍 ,骨髓有核细胞数明显下降 ,同时骨髓和外周血单个核细胞表面CD49d表达以及细胞黏附能力都有所下降 ,而对照组无类似现象。结论　G CSF可能通过降低某些黏附分子的表达 ,削弱造血细胞与骨髓基质的黏附而产生动员效果

Role of Adhesion Molecules on Cell Surface During Mobilization of Hematopoietic Cells

Purpose To study the change of adhesion molecules' expression during the mobilization in peripheral blood stem cell transplantation,confirm the influence of granulocyte colony stimulating factor(G?CSF) on stem cells in peripheral blood stem cell transplantation(PBSCT). Methods Mice were injected subcutaneously with diluted G?CSF(filgrastim) or normal saline for 7 days.The blood Sca?1 stem cell count and bone marrow nucleated cell count were made.The expressions of CD49d and CD44 and the adhesive ability of mononuclear cells to fibronectin(FN) were examined by flow cytometry(FCM) and 51 Cr adhesive assay respectively. Results The mobilizing effect of G?CSF to mice was the same as to human.The number of Sca?1 cells in peripheral blood(PB) reached the peak on the seventh day,and the bone marrow(BM) nucleated cell count was reduced,meanwhile the expressions of CD49d and the cells' adhesive ability in BM and PB declined. Conclusions G?CSF can reduce some cell adhesion molecules' expression and the adhesive ability of hematopoietic stem cells(HSC) to BM matrix so that it can mobilize HSC from BM to PB.