HIV gp41融合多肽对抗原特异性Treg活化的抑制作用

目的探讨HIV gp41融合多肽(fusion peptide,FP)与机体免疫细胞的相互作用,观察FP能否影响抗原特异性的调节性T细胞活化。方法用免疫磁珠分离DO11.10小鼠脾脏CD4+CD25+调节性T细胞(Treg)、CD4+CD25-效应性T细胞(Teff)共培养,3d后采用CCK-8法分析FP对OVA323-339抗原激活的Treg抑制Teff细胞增殖的影响。另外,ELISA法检测FP对Treg细胞IL-10分泌的影响,荧光共聚焦分析FP多肽在Treg细胞表面与TCR的共分布。结果25 mg·L-1的FP能降低Treg的抑制活性和IL-10分泌,在活化的Treg细胞表面有FP和TCR荧光的重叠。结论 FP降低抗原特异性Treg细胞的抑制功能,可能与其抑制IL-10合成有关;它与TCR在细胞膜的相互作用也可能影响APC向Treg细胞递呈活化信号,干扰Treg的活化。

Inhibitory effects of HIV gp41 fusion peptide on the antigen-specific regulatory T cells activation

Aim To investigate whether FP could affect antigen specific regulatory T cell(Treg) activation in order to explore the interactions between HIV gp41 fusion peptide(FP)and the immune cells.Methods CD4 + CD25 + regulatory T cells(Treg)and CD4 + CD25effect T cells(Teff) were separated from splenocytes of DO11.10 OVA TCR Tg mice by immune magnetic beads and co-cultured for 3 days.Treg could inhibit the proliferation of co-cultured Teff cells after OVA323-339 stimulation,meanwhile the effects of FP on this Treg function were also observed by CCK-8 assay.The effects of FP on antigen stimulated IL-10 secretion of Treg were measured by ELISA.The distribution of FP and TCR on the Treg cell membrane was observed by fluorescent confocal.Results FP at a concentration of 25 mg · L-1 reduced the Treg function, down-regulated IL-10 production in antigen activated Treg cells.The fluorescence of TCR and FP overlapped on the cell surface of activated Treg.Conclusion HIV gp41 fusion peptide may reduce the Treg function by inhibiting IL-10 secretion,disturbing the cross-talk between TCR and APC during Treg activation.