TGF-β1诱导的新生儿脐带血CD4^＋CD25^＋调节性T细胞增殖动力学研究

目的：探讨转化生长因子-β1（transforming growth factor-β1,TGF-β1）诱导的新生儿脐带血CD8^＋CD25^＋调节性T细胞增殖活性。方法：新生儿脐带血单个核细胞经羧基荧光素乙酰乙酸琥珀酰亚胺酯（carboxyfluorescein diacetate,succinimidyl ester,CFSE）标记后,加入TGF-β1,同时用CD3mAb激活和IL-2培养扩增。培养第4、6、8天收集细胞,用流式细胞术检测活化增殖后的CD4^＋CD25^＋、CD8^＋T细胞增殖动力学变化。结果：培养后第6、8天,实验组CD4^＋CD25^＋T细胞增殖指数分别为11.52、23.04,高于对照组CD4^＋CD25^＋T细胞（6.68,10.46）及实验组CD8^＋T细胞（4.23,5.43）。培养后第8天,实验组CD4^＋CD25^＋T细胞第8代到第10代所占的比例为52.74%,在各代中以第8代所占比例最高,而对照组CD4^＋CD25^＋T细胞第8代到第10代所占的比例为36.26%;实验组CD8^＋T细胞第8代到第10代所占的比例为13.54%,在各代中所占比例最高的为第2代,而对照组CD4^＋T细胞第8代到第10代所占的比例为29.44%。结论：TGF-β1诱导的新生儿脐带血CD4^＋CD25^＋调节性T细胞增殖活性明显强于CD8^＋T细胞。

The dynamics study of proliferation of CD4+CD25+ Treg cells induced by transforming growth factor-β1 in neonatal cord blood

Objective：To explore proliferative activity of CD4^＋CD25^＋ Treg cells induced by transforming growth factor-β1（TGF-β1）in neonatal cord blood.Methods：Cord blood mononuclear cells were labeled with carboxyfluorescein diacetate,succinimidyl ester（CFSE）,and then stimulated with TGF-β1,CD3mAb and cultured in 10% NBS-1640 medium in presence of IL-2.The dynamics of proliferation of CD4^＋CD25^＋ and CD4^＋ T cells on day 4,day 6,day 8 after culture was determined by flow cytometry.Results：Proliferative kinetics analysis showed proliferation index（PI）on day 6 and day 8 of culture with TGF-β1 in CD4^＋CD25^＋ Treg cells（11.52 and 23.04）were significantly higher than those in control cells（6.68 and 10.46）and those cultured with TGF-β1 in CD4^＋ T cells（4.23 and 5.43）.On day 8 of culture with TGF-β1,proportion of the generations from 8th to 10th in CD4^＋CD25^＋ Treg（52.74%）was strikingly higher than those in control cells（36.26%）and those in CD4^＋ T cells cultured with TGF-β1（13.54%）,while the proportion of the generations from 8th to 10th in control CD8^＋ T cells was 29.44%.Conclusions：Proliferative activity of CD4^＋CD25^＋ Treg cells induced by TGF-β1 in neonatal cord blood was obviously stronger than that of CD8^＋ T cells.