体外扩增对脐带血CD34~+细胞归巢相关分子影响的研究

目的体外探讨脐带血CD34+细胞经细胞因子刺激后的增殖、分化以及表面归巢相关分子的表达。方法磁珠分选出脐血CD34+细胞,无血清培养基培养14d。实验分组:A组:培养基对照组;B组:SCF+TPO+Flt3;C组:SCF+TPO+Flt3+IL-3;应用流式细胞仪检测扩增前后CD34+细胞CD33、CD41、CD71、CD62L、CD162、CLA、CD44、CD11a、CD18、CD184、CD26表达;用半固体培养基培养集落形成单位(CFU)。结果 B、C两组有核细胞、CD34+细胞和CFU都得到有效扩增,C组的有核细胞、CFU扩增倍数明显高于B组(P<0.01),但CD34+细胞扩增倍数低于B组(P<0.01);扩增后的CD34+细胞表达CD33、CD41、CD71的比例增加,其中C组的增加尤为显著;扩增后CD62L、CD162、CD44的表达减低,其中C组CD62L、CD44减低更明显;而CLA、CD11a、CD18、CD184、CD26表达均上调,C组的CLA、CD11a、CD18、CD184上调更为明显。结论脐血CD34+细胞经过细胞因子的扩增,虽然有核细胞及祖细胞的量增加了,但细胞发生分化,分化因子的作用更为明显。扩增的CD34+细胞表面部分与归巢相关的分子表达上调,有促进细胞归巢的作用。

Study on Influence of the Homing Related Molecules on Umbilical Cord Blood CD34+ Cells after Amplified with Cytokines in vitro

Objective To investigate the proliferation, differentiation and the expression of homing-related molecules on umbilical cord blood CD34^＋ cells after stimulated with cytokines in vitro. Methods Umbilical cord blood CD34^＋ cells were isolated by magnetic bead,then cultured in serum-free medium for 14 days. Experimental groups were as followed：Group A.. medium control~ Group B： supplemented with SCF,TPO and Flt3~ Group C.. supplemented with SCF, TPO, Flt3 and IL-3. The expression of CD33, CD41, CD71, CD62L, CLA, CD162, CD44, CDlla, CD18, CD184 and CD26 on CD34^＋ cells were analyzed by flow cytometry. The colony forming units （CFU） were cultured in semisolid medi- um for 14 days. Results The nucleated cells, CD34^＋ cells and CFU were amplified efficiently in group B and C. The am- plified efficiency o~ nucleated cells or CFU in group C was higher obviously than group B （P~0. 01）, but CD34^＋ cells was lower obviously than group B （P d0.01）. The expression of CD33, CD41 and CD71 on CD34^＋cells increased significantly after amplified, which C group increased more obviously. The expression of CD62L, CD162 and CD44 on CD34^＋ cells down-regulated after amplified, the decrease of CD62L and CD44 was more obvious in group C. But the expression of CLA, CDlla, CD18, CD184 and CD26 increased after amplified. The expression of CLA, CDlla, CD18 and CD184 in- creased more obviously in group C. Conclusions Despite an increase in the amount of nucleated cells and progenitors cells after stimulated with cytokines, CD34^＋ cells differentiated, the effect of differentiation factor was more obvious. The expression of some homing-related molecules on CD34^＋ cells increased after amplified, which promoted those ceils homing in bone marrow.