【作者】 李文杰；

【导师】 崔凡；

【作者基本信息】 电子科技大学 ， 临床医学（专业学位）， 2025， 硕士

【摘要】 目的:本研究旨在比较健康个体与尚未进展至AIDS阶段的HIV感染者肠粘膜组织的病理学差异,分析肠粘膜中NLRP3炎症小体相关分子(NLRP3、Caspase-1)、紧密连接蛋白(ZO-1、Occludin)以及血清炎症因子(IL-1β、IL-18)和肠粘膜损伤标志物(DAO、LPS)的表达水平,探讨HIV慢性无症状感染阶段肠粘膜屏障损伤的程度及其与NLRP3炎症小体介导的细胞焦亡(pyroptosis)之间的潜在关联。方法:依据纳排标准,将研究对象分为HIV-1感染组(HIV组,未进展至AIDS期)20例和健康对照组(HC组)15例。收集受试者血清样本,采用酶联免疫吸附测定(ELISA)检测血清肠粘膜损伤标志物(DAO、LPS)及细胞焦亡相关炎症因子(IL-1β、IL-18)的表达水平。获取受试者肠粘膜组织样本,通过HE染色观察组织病理学变化,并采用蛋白质印迹(Western blot,WB)和免疫组织化学(Immunohistochemistry,IHC)检测肠粘膜中NLRP3、Caspase-1的表达水平,同时通过WB检测ZO-1和Occludin的表达情况。结果:(1)免疫学特征:HIV组CD4+T细胞计数显著低于HC组。(2)组织病理学变化:HC组肠粘膜结构完整,腺体排列规则;HIV组表现出粘膜上皮细胞脱落、腺体排列稀疏、局灶性细胞坏死及炎症细胞浸润。(3)肠粘膜屏障损伤:HIV组肠粘膜组织中ZO-1和Occludin蛋白表达显著低于HC组;血清LPS水平在HIV组显著升高,而DAO水平在两组间差异无统计学意义。(4)焦亡相关炎症因子:HIV组血清IL-1β和IL-18水平显著高于HC组。(5)NLRP3炎症小体相关分子:WB和IHC检测结果均显示HIV组肠粘膜中NLRP3及Caspase-1表达水平显著高于HC组。(6)相关性分析:肠粘膜NLRP3表达水平与Caspase-1、血清IL-1β及IL-18呈显著正相关,与ZO-1及Occludin的表达呈显著负相关。结论:在HIV慢性无症状感染阶段,肠粘膜已出现明显的组织学损伤和屏障功能受损,表现为肠道紧密连接蛋白下调及炎症因子升高。同时,NLRP3炎症小体在HIV感染者肠粘膜中呈高表达状态,其异常激活可能通过介导细胞焦亡促进肠粘膜屏障破坏。这一机制可能在HIV相关肠道免疫病理过程中发挥重要作用。更多还原

【Abstract】 Objective:This study aims to compare the pathological differences in intestinal mucosal tissues between healthy individuals and HIV-infected patients who have not progressed to the AIDS stage.It analyzes the expression levels of NLRP3inflammasome-related molecules(NLRP3,Caspase-1),tight junction proteins(ZO-1,Occludin),serum inflammatory cytokines(IL-1β,IL-18),and intestinal mucosal injury markers(DAO,LPS).The goal is to investigate the extent of intestinal mucosal barrier damage during the chronic asymptomatic phase of HIV infection and its potential association with NLRP3 inflammasome-mediated pyroptosis.Methods:Based on predefined inclusion and exclusion criteria,the study enrolled 20 HIV-1-infected individuals who had not progressed to AIDS(HIV group)and 15 healthy controls(HC group).Serum samples were collected from all participants,and enzyme-linked immunosorbent assay(ELISA)was employed to quantify the levels of intestinal mucosal injury markers—diamine oxidase(DAO)and lipopolysaccharide(LPS)—as well as pyroptosis-associated inflammatory cytokines interleukin-1β(IL-1β)and interleukin-18(IL-18).Intestinal mucosal tissue samples were obtained for histopathological examination using hematoxylin and eosin(HE)staining.The expression levels of NLRP3 and Caspase-1 in the intestinal mucosa were assessed via Western blotting(WB)and immunohistochemistry(IHC),while the tight junction proteins ZO-1 and Occludin were analyzed using WB.Results:(1)Immunological characteristics:The CD4+T cell count in the HIV group was significantly lower than that in the HC group.(2)Histopathological changes:The intestinal mucosa in the HC group showed intact structure and regularly arranged glands;in contrast,the HIV group exhibited epithelial cell shedding,sparse glandular arrangement,focal necrosis,and inflammatory cell infiltration.(3)Intestinal mucosal barrier damage:The expression levels of ZO-1 and Occludin proteins in the intestinal mucosa were significantly lower in the HIV group compared to the HC group.Serum LPS levels were significantly elevated in the HIV group,while DAO levels showed no statistically significant difference between the two groups.(4)Pyroptosis-related inflammatory cytokines:Serum levels of IL-1βand IL-18were significantly higher in the HIV group than in the HC group.(5)NLRP3 inflammasome-related molecules:Both WB and IHC results showed that the expression levels of NLRP3 and Caspase-1 in the intestinal mucosa were significantly higher in the HIV group than in the HC group.(6)Correlation analysis:The expression level of NLRP3 in the intestinal mucosa was significantly positively correlated with Caspase-1,serum IL-1β,and IL-18 levels,and significantly negatively correlated with the expression of ZO-1 and Occludin.Conclusion:During the chronic asymptomatic stage of HIV infection,significant histological damage and impairment of intestinal mucosal barrier function are already present,characterized by downregulation of tight junction proteins and elevated inflammatory cytokines.Meanwhile,the NLRP3 inflammasome is highly expressed in the intestinal mucosa of HIV-infected individuals,and its aberrant activation may contribute to mucosal barrier disruption by mediating pyroptosis.This mechanism may play an important role in the gut immune pathogenesis associated with HIV infection.更多还原