灭活HIV-1颗粒对HT-29细胞增殖、凋亡和紧密连接的影响

The effects of inactivated HIV-1 particles on proliferation, apoptosis and tight junction of HT-29 cells

目的通过研究灭活HIV-1IIIB颗粒对人结肠癌HT-29细胞的增殖、凋亡和紧密连接的影响,探讨HIV-1病毒子在"AIDS肠道病灶论"中的直接作用机制。方法将AT-2灭活的HIV-1IIIB颗粒加入到HT-29培养系统中,使p24抗原终质量浓度为1 ng/ml;WST-1法检测HT-29的增殖率;运用流式细胞术检测HT-29中Ki-67和Apo2.7的表达以及线粒体膜电势和线粒体质量的变化;运用流式细胞术检测HT-29紧密连接蛋白Occludin的表达。结果灭活HIV-1IIIB抑制HT-29增殖并抑制Ki-67表达;灭活HIV-1IIIB诱导HT-29凋亡并降低线粒体膜电势和线粒体质量;灭活HIV-1IIIB下调Occludin表达,提示其破坏细胞的紧密连接。结论 AT-2灭活HIV-1IIIB能够抑制HT-29增殖,诱导HT-29凋亡,并破坏HT-29紧密连接,提示在"AIDS肠道病灶论"中,导致肠黏膜屏障完整性受损的因素除了HIV-1引发的"旁观者效应"外,HIV-1病毒子本身可以对肠上皮细胞(intestinal epithelial cell,IEC)产生细胞毒作用;而肠黏膜通透性增加会引起肠菌转位,继而引发系统性免疫过度活化。

This study was conducted to explore the effects of AT-2-inactivated HIV-1 particles on the proliferation, apoptosis and tight junction of HT-29 cells. HIV-1ⅢB particles were inactivated by AT-2 chemical and then added to HT-29 culture system in optimal concentration. The proliferation and Ki-67 expression of HT- 29 was evaluated by WST-1 assay and flow cytometry, respectively. The apoptosis of HT-29 was evaluated by Apo2.7 staining, as well as DIOC6（3） and NAO staining. Meanwhile, the tight junction of HT-29 was assessed by Occludin staining. Data showed that the proliferation of HT-29 was inhibited by AT-2-inactivated HIV-1ⅢB particles. In addition, AT-2-inactivated HIV-1ⅢBparticles induced HT-29 apoptosis, and disrupted the tight junction of HT-29. The results indicated that AT-2-inactivated HIV-1ⅢB particles strikingly affected the proliferation, apoptosis and tight junction of HT-29 cells, which means besides its immunopathogenicity, the eytopathogenicity of HIV-1 virion contributes to the intestinal pathogenesis of AIDS. The increased intestinal permeability might result in gut bacteria transloeation, which then triggers systemic immune hyperactivation.