Foxp3基因转染对人CD4+CD25-T细胞表型和功能的影响

目的探讨体外Foxp3基因表达对CD4^＋ CD25^-T细胞功能的影响。方法将编码人Foxp3基因全长的逆转录病毒表达载体，转染人外周血CD4^＋CD25^-T细胞。以流式细胞仪方法检测转染后CD4^＋CD25^-T细胞表面CD25、CDl27分子及CTLA4分子的表达变化，以流式细胞仪及RT—PCR检测Foxp3基因在转染细胞中的表达。体外刺激、观察转染后的Foxp3细胞的增殖反应，以及重组细胞对CD4^＋CD25^-T细胞增殖反应和细胞因子分泌的作用。结果转染后Foxp3基因在CD4^＋CD25^-T细胞中呈高水平表达。转染细胞表面CD25、CTLA4分子均呈高水平表达，而CDl27分子表达水平下降，且IL-2并不能诱导其增殖。转染细胞与CD4^＋CD25^-T细胞共同培养可有效抑制CD4^＋CD25^-T细胞的增殖反应及细胞因子IL-4、IL-5和IFN-γ的分泌。结论Foxp3基因转染可有效诱导CD25及CTLA4分子表达，并使转染细胞具有调节性T细胞的功能。

Changes of phenotype and function of human CD4+CD25- T cells induced after Foxp3 transfection

Objective To explore the effects of Foxp3 gene transfection on the phenotype and function of CD4 CD25-T cells.Methods The pMSCV-Foxp3 retroviral vector encoding Foxp3 gene was transfected into PT67 packaging cell line.Virus-containing supernatant was applied to differentiated CD4 CD25-T cells,then the cells were sorted with flow cytometry.The expressions of CD25,CD127,CTLA4 and proliferation of transfected CD4 CD25-T cells were examined.The effect of transfected CD4 CD25-T cells on the proliferation and cytokine production of CD4 CD25-T cells were examined.Results Foxp3 gene transfected CD4 CD25-T cells could express Foxp3.Transfection of Foxp3 gene upregulated the expressions of CD25 and CTLA-4,but down-regulated CD127 expression.After transfection,the proliferation of CD4 CD25-T cells was eliminated.IL-2 could not induce the proliferation of transfected T cells.Transfected T cells inhibited the proliferation of CD4 CD25-T cells after coculture.Conclusion CD4 CD25-T cells acquired a regulatory phenotype and function after transfected with Foxp3 gene,indicating a key role of Foxp3 in the generation of CD4 CD25 regulatory T cells.