中国92例HIV／AIDS患者HIV-1gp412F5和4E10中和抗体表位变异研究

Amino acid mutations of gp41 2F5 and 4E10 neutralizing epitopes of 92 HIV-1 infected individuals and AIDS patients in China

目的探讨92例HIV／AIDS患者HIV-1病毒近膜端（membrane proximal external region，MPER）中和抗体2F5和4E10保守表位ELDKWA、NWFDIT氨基酸变异特点，为中国HIV／AIDS患者免疫治疗以及疫苗设计提供数据。方法Nest-PCR扩增HIV-1env区gp41段基因，核酸序列测定，翻译为氨基酸与HIV-1Sequence Database HXBⅡ参考株中和抗体表位数据比对，分析2F5、4E10中和表位氨基酸变异情况。结果92例HIV／MDS患者HIV-1外膜蛋白env gp41段中和抗体2F5、4E10保守表位氨基酸均存在突变；2F5中和抗体表位主要有E662A（14．1％）、K665S（17．4％）、A667K（16．3％）突变；4E10中和抗体表位主要有N671S（13．0％）、D674S（3．3％）、T676S（16．3％）突变；CRF_B’C亚型与B’亚型的2F5和4E10表位氨基酸突变差异具有统计学意义（P〈0．05）；CRF—B’C与CRF01_AE亚型2F5表位突变差异具有统计学意义（P〈0．05）；B’亚型缓慢进展者、HIV感染者和MDS患者的4E10表位氨基酸突变差异具有统计学意义（P〈0．05）。结论92例HIV／AIDS患者HIV-1包膜蛋白env gp41段中和抗体2F5、4E10中和表位氨基酸存在突变，且变异多样化；不同亚型中和抗体保守表位氨基酸位点变异有差异；B’亚型4E10中和抗体表位变异可能与疾病进展有一定联系。

Objective To study the amino acid mutations in neutralizing antibody 2F5 and 4El0 conserved epitopes ELDKWA and NWFDIT of HIV-1 membrane proximal external region （MPER） in 92 HIV-infected individuals and AIDS patients in China, and to provide a basis for the neutralizing antibodies immunotherapy and a design of vaccines. Methods Nest-PCR methods were used to amplify genes of the HIV-1 env gp41 region. The amplified fragments were sequenced by double-deoxygen terminal method and translated into amino acids for analysis. The mutations of 2F5 and 4E10 neutralizing epitopes were identified by comparison with the epitopes reference data in HIV-1 Sequence Database. Results There were mutations on both 2F5 and 4E10 neutralizing epitopes. 2F5 conserved neutralizing epitopes major mutations focused on E662A （ 14.1% ）, K665S （ 17.4% ）, A667K （ 16.3% ）, and 4E10 conserved neutralizing epitopes major mutations included N671S （ 13.0%0 ）, D674S（3.3% ）, T676S（16.3% ）. The mutation rates of 2F5 and 4E10 epitopes were significantly different between CRF_B＇C-clade and B＇-clade （P 〈0.05）. The mutation rates of CRF_B＇C-clade were higher than that of CRF01_AE-clade in 2F5 epitopes （P 〈 0.05）. The mutation rates of B＇-clade in 4El0 eiptopes showed significant difference in slow progressors, HIV-infected individuals and AIDS patients, respectively （P 〈 0.05）. Condnsion The HIV-1 patients in China are demonstrated diversified mutations in 2F5 and 4El0 neutralizing epitopes. The mutation degrees of amino acids in conserved neutralizing epitopes are different in different subtypes. There may be a correlation between neutralizing epitopes mutations of 4E10 with disease progression.