Background Studies on human immunodeficiency virus type 1 （HIV-1） vaccines have recently focused on targeting the conserved neutralizing epitopes 2F5 and 4E10, and hence it is important to understand the extent of m...Background Studies on human immunodeficiency virus type 1 （HIV-1） vaccines have recently focused on targeting the conserved neutralizing epitopes 2F5 and 4E10, and hence it is important to understand the extent of mutations in these two viral epitopes. Here, we investigated the amino acid mutations in epitopes of 2F5 （ELDKWA, HIV-1 HXB2 env 662-667 aa） and 4E10 （NWFDIT, HIV-1 HXB2 env 671-676 aa） in the membrane proximal-external region of gp41 from clade B＇ HIV-1-infected individuals living in Henan province, China. We also examined the frequency of a mutation and its relation to disease progression.Methods A cohort of 54 treatment-na（i）ve HIV-1-infected individuals was recruited in this study, and 16 individuals were selected for a short-term longitudinal study on sequence evolution. The HIV-1 env gp41 gene was amplified, cloned, and sequenced, and predicted amino acid sequences were aligned for analysis.Results The mutations E662A and K665E on the 2F5 epitope and N671S and T676S on the 4E10 epitope were seen.Simultaneous RNA sequencing showed some discrepancies with proviral DNA sequences. In our longitudinal study,mutation levels of these two neutralizing epitopes were low but diverse and persistent. The frequencies of mutations within the 4E10 peptide NWFDIT in slow progressors were noticeably lower than those in AIDS patients （P ＜0.05）.Conclusions Antigenic variation of the neutralizing epitopes 2F5 and 4E10 is limited in subtype B＇ infection, and that 4E10 peptide mutation is correlated with disease progression. Monitoring epitope mutations will offer useful data for development of the candidate 2F5-like and 4E10-like antibodies to prevent and treat AIDS.展开更多
人类Ⅰ型免疫缺陷病毒(human immunodeficiency class I, HIV-1)包膜蛋白gp41的近膜端外部区(membrane proximal external region, MPER)在HIV-1的各个分化株之间相当保守,这暗示MPER区对于病毒的生存和侵染均具有十分重要的作用.目前...人类Ⅰ型免疫缺陷病毒(human immunodeficiency class I, HIV-1)包膜蛋白gp41的近膜端外部区(membrane proximal external region, MPER)在HIV-1的各个分化株之间相当保守,这暗示MPER区对于病毒的生存和侵染均具有十分重要的作用.目前研究表明,两个靶向HIV-1且具有最广泛中和活性的单抗2F5和4E10,都特异地识别该区域,进而有效地抑制包膜蛋白介导的病毒膜融合过程.我们先前的研究表明,4E10抗体表位的抗原性和免疫原性会随着gp41融合核心区域的结构调整而发生显著的改变,提示在gp41蛋白的MPER区与融合核心区之间很有可能存在某种联系,并与gp41介导的膜融合过程相关.本研究利用各种不同的gp41融合核心区衍生多肽,检测了4E10表位多肽(D4E10P)与它们之间的反应性.其中,具有gp41蛋白核心区N-trimer结构的多肽(N-trimer-6HB)显示出很强的结合活性.进一步对N-trimer-6HB多肽进行噬菌体文库筛选,发现4E10表位上一个短的模体序列(WF)很有可能对gp41的N-trimer和MPER区之间的相互作用发挥了至关重要的作用,导致MPER区以潜在的方式参与病毒包膜和靶细胞膜间的融合过程.展开更多
The membrane proximal external region (MPER) of gp41 is extremely conserved among diverse HIV-1 variants, implying its important role in viral infection. Interestingly, two of the most broadly neutralizing antibodies,...The membrane proximal external region (MPER) of gp41 is extremely conserved among diverse HIV-1 variants, implying its important role in viral infection. Interestingly, two of the most broadly neutralizing antibodies, 2F5 and 4E10, specifically recognize this region. Our previous study demonstrated that the antigenicity and immunogenicity of 4E10 epitope are affected by remodeling gp41 fusion core, suggesting that the MPER may be associated with gp41 core and involved in gp41-mediated membrane fusion. Here we measured the binding activity of 4E10 epitope peptide (D4E10P) with various gp41 core-derived peptides and found that the N-trimer region in a construct designated N-trimer-6HB interacted significantly with D4E10P. Using N-trimer-6HB to screen a phage library, we identified a motif (WF) located in 4E10 epitope that may play a certain role in the interaction of gp41 MPER with the N-trimer in gp41 fusion core and, we thus speculated upon the potential involvement of MPER in the fusion process between viral envelope and target cell membrane.展开更多
文摘Background Studies on human immunodeficiency virus type 1 （HIV-1） vaccines have recently focused on targeting the conserved neutralizing epitopes 2F5 and 4E10, and hence it is important to understand the extent of mutations in these two viral epitopes. Here, we investigated the amino acid mutations in epitopes of 2F5 （ELDKWA, HIV-1 HXB2 env 662-667 aa） and 4E10 （NWFDIT, HIV-1 HXB2 env 671-676 aa） in the membrane proximal-external region of gp41 from clade B＇ HIV-1-infected individuals living in Henan province, China. We also examined the frequency of a mutation and its relation to disease progression.Methods A cohort of 54 treatment-na（i）ve HIV-1-infected individuals was recruited in this study, and 16 individuals were selected for a short-term longitudinal study on sequence evolution. The HIV-1 env gp41 gene was amplified, cloned, and sequenced, and predicted amino acid sequences were aligned for analysis.Results The mutations E662A and K665E on the 2F5 epitope and N671S and T676S on the 4E10 epitope were seen.Simultaneous RNA sequencing showed some discrepancies with proviral DNA sequences. In our longitudinal study,mutation levels of these two neutralizing epitopes were low but diverse and persistent. The frequencies of mutations within the 4E10 peptide NWFDIT in slow progressors were noticeably lower than those in AIDS patients （P ＜0.05）.Conclusions Antigenic variation of the neutralizing epitopes 2F5 and 4E10 is limited in subtype B＇ infection, and that 4E10 peptide mutation is correlated with disease progression. Monitoring epitope mutations will offer useful data for development of the candidate 2F5-like and 4E10-like antibodies to prevent and treat AIDS.
文摘人类Ⅰ型免疫缺陷病毒(human immunodeficiency class I, HIV-1)包膜蛋白gp41的近膜端外部区(membrane proximal external region, MPER)在HIV-1的各个分化株之间相当保守,这暗示MPER区对于病毒的生存和侵染均具有十分重要的作用.目前研究表明,两个靶向HIV-1且具有最广泛中和活性的单抗2F5和4E10,都特异地识别该区域,进而有效地抑制包膜蛋白介导的病毒膜融合过程.我们先前的研究表明,4E10抗体表位的抗原性和免疫原性会随着gp41融合核心区域的结构调整而发生显著的改变,提示在gp41蛋白的MPER区与融合核心区之间很有可能存在某种联系,并与gp41介导的膜融合过程相关.本研究利用各种不同的gp41融合核心区衍生多肽,检测了4E10表位多肽(D4E10P)与它们之间的反应性.其中,具有gp41蛋白核心区N-trimer结构的多肽(N-trimer-6HB)显示出很强的结合活性.进一步对N-trimer-6HB多肽进行噬菌体文库筛选,发现4E10表位上一个短的模体序列(WF)很有可能对gp41的N-trimer和MPER区之间的相互作用发挥了至关重要的作用,导致MPER区以潜在的方式参与病毒包膜和靶细胞膜间的融合过程.
基金Supported by National Key Basic Research and Development Program of China (Grant No. 2007CB914402)
文摘The membrane proximal external region (MPER) of gp41 is extremely conserved among diverse HIV-1 variants, implying its important role in viral infection. Interestingly, two of the most broadly neutralizing antibodies, 2F5 and 4E10, specifically recognize this region. Our previous study demonstrated that the antigenicity and immunogenicity of 4E10 epitope are affected by remodeling gp41 fusion core, suggesting that the MPER may be associated with gp41 core and involved in gp41-mediated membrane fusion. Here we measured the binding activity of 4E10 epitope peptide (D4E10P) with various gp41 core-derived peptides and found that the N-trimer region in a construct designated N-trimer-6HB interacted significantly with D4E10P. Using N-trimer-6HB to screen a phage library, we identified a motif (WF) located in 4E10 epitope that may play a certain role in the interaction of gp41 MPER with the N-trimer in gp41 fusion core and, we thus speculated upon the potential involvement of MPER in the fusion process between viral envelope and target cell membrane.
