【作者】 孙坚萍；

【导师】 邵一鸣； 马丽英；

【作者基本信息】 中国疾病预防控制中心 ， 免疫学， 2008， 博士

【摘要】 HIV病毒感染机体后产生的保护性免疫反应知之甚少,这对设计有效的AIDS疫苗是个巨大的挑战。此外,我国HIV流行毒株与欧美、非洲流行毒株不同,我国流行毒株主要包括B’/C重组和B’亚型。我们对B’/C重组和B’亚型HIV-1感染者的中和免疫进行了系统研究,并从gp120基因方面探讨HIV病毒中和免疫的逃逸机制。从我国不同流行地区HIV-1感染者中收集新鲜血,分离感染者血浆和PBMC。利用国际上公认的TZM-bl细胞系方法检测感染者血浆的中和免疫;ELISA方法检测感染者血浆对SHIV_chn19Env单肽的结合抗体水平。采用传统的共培养法分离临床病毒;GHOST细胞系测定分离毒株的辅助受体利用;TZM-bl细胞系检测分离毒株的中和敏感性;巢式RT-PCR扩增分离毒株gp120序列;Bioedit和MEGA软件分析氨基酸序列。结论:1.对实验室标准毒株和临床分离毒株,B’/C感染者血浆中和水平均低于B’感染者血浆。2.HIV-1感染者血浆对同亚型内的临床分离病毒同源中和作用较好,而亚型间异源中和作用普遍偏低。3.存在部分感染者血浆有相对广谱的中和活性。4.HIV-1病毒可逃逸自身血浆的中和免疫。但是存在能被自身血浆低水平中和的分离病毒。5.感染者血浆对SHIV_chn19Env单肽的结合抗体水平和血浆中和活性之间未发现相关关系。6.HIV-1感染者血浆中和水平和相对应的分离毒株的中和敏感性之间存在负相关关系。7.gp120区N-糖基化位点增多是临床分离毒株逃逸机体中和免疫压力的机制之一。8.V3区序列的不同决定B’/C重组毒株利用CCR5辅助受体,而B’亚型毒株可从利用CCR5辅助受体转向利用CXCR4辅助受体。本研究首次对我国广泛流行的HIV-1B’/C重组以及B’亚型感染者的中和免疫、临床分离毒株的中和敏感性进行了系统分析,并从分子水平探讨临床分离毒株的中和免疫逃逸机制。该结果为更好地理解HIV的致病机制,研制有效的AIDS疫苗提供了重要的参考价值。更多还原

【Abstract】 The protective immune response of HIV-1 infected individuals is still unclear.In China,the epidemic HIV strains included B’/C recombinant and subtype B’ were different form those of Europe and Africa.We just study the neutralization respongse of HIV-1 infected individuals,and try to explain the escape mechanism from gp120 sequence.Plasmas from HIV-1 infected individuals in different epidemic area(Xinjiang Vygur Autonomous Region and Anhui province) were collected.Neutralization response of B’/C recombinant and subtype B’infected individuals detected by TZM-bl cell line;Binding antibody to SHIVchn19Env peptide of plasmas tested by ELISA. Coculture with negative PBMC to isolate clinical viruses;GHOST cell line analysis the coreceptor usage;gp120 sequences were expanded by RT-PCR and anlysised by bioedit software.Collusions:1.The neutralization level of plasmas from HIV-1 B’/C recombinant infected individuals were lower than that of plasmas form subtype B’infected individuals.2.The intrasubtype neutralization level of plasma was higher than intersubtype neutralization level.3.It has been found few plasma from HIV-1 infected individuals have higher and broadly cross neutralization level.4.Most HIV infected individuals could not neutralize the autologous isolates;however,there were few HIV infected individuals could neutralize autologous isolate with low level.5.There were no correlation between binding antibody and neutralization level of plasmas from HIV-1 infected individuals.6.There were negative correlation between neutralization sensitivity of HIV-1 isolates and neutralization level of plasmas from infected individuals.7.HIV-1 isolates could escape the neutralization pressure by adding N-glycans of gp 120 region.8.V3 structure determined the coreceptor usage.We first study the neutralization response of B’/C recombinant and B’ subtype infected individuals.And try to explore the escape mechanism of isolates.This may help to develop the more effective AIDS vaccine.更多还原