Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China; Guangdong Provincial Key Laboratory of Tropical Disease Research, Guangzhou, China.
Department of Epidemiology, School of Public Health, Southern Medical University, Guangzhou, China; Guangdong Provincial Key Laboratory of Tropical Disease Research, Guangzhou, China; Dermatology Hospital, Southern Medical University, Guangzhou, China.
Virus Res. 2019 Apr 15;264:16-21. doi: 10.1016/j.virusres.2019.02.010. Epub 2019 Feb 19.
To characterize HIV-1 gp41 as an antigen for developing HIV-1 incidence assay and to investigate the impact of HIV-1 genetic diversity on the assay performance, a number of truncated peptides were synthesized to identify the immunodominant epitopes (IDEs) of HIV-1 gp41 protein. Subsequently, the mixed peptides (MP3) or the recombinant protein (MP4) containing HIV-1 gp41 IDEs of the major HIV-1 genotype CRF01_AE, CRF07_BC/ CRF08_BC and subtype B in China were used to verify the sensitivity and specificity of HIV-1 recency testing. We identified the QKFLG and GKIIC motifs located in the loop region of HIV-1 gp41 as the two major IDEs. The surrounding amino acids EAQQHLLQLT and WNSSWSN could block the binding of gp41 peptide and anti-HIV antibody with low avidity, making the gp41 peptide p57 suitable for distinguishing recent and long-term HIV-1 infections. Furthermore, MP3 or MP4-based immunoassay could significantly improve the assay sensitivity and showed 93.33% (140/150) vs. 94.59% (35/37) and 94.08% (143/152) vs. 94.59% (35/37) concordance with commercially available LAg-Avidity EIA test among the cross-sectional and longitudinal samples, respectively. The estimated mean duration of recent infection (MDRI) was 130 days (95% CI: 83-167) and 166 days (95% CI: 123-202) for MP3 and MP4 assays, respectively. Our preliminary results indicate that the HIV-1 gp41 peptide-based immunoassay specifically targeting the major HIV-1 genotype CRF01_AE, CRF07_BC/CRF08_BC and subtype B could serve as a simple incidence assay for differentiating recent and long-term HIV-1 infections in China.
为了将 HIV-1 gp41 作为开发 HIV-1 发病率检测的抗原，并研究 HIV-1 遗传多样性对检测性能的影响，合成了一些截断肽以鉴定 HIV-1 gp41 蛋白的免疫显性表位 (IDEs)。随后，使用包含中国主要 HIV-1 基因型 CRF01_AE、CRF07_BC/CRF08_BC 和亚型 B 的 HIV-1 gp41 IDE 的混合肽 (MP3) 或重组蛋白 (MP4) 来验证 HIV-1 近期检测的敏感性和特异性。我们确定了位于 HIV-1 gp41 环区的 QKFLG 和 GKIIC 基序为两个主要的 IDE。周围的氨基酸 EAQQHLLQLT 和 WNSSWSN 可以阻止 gp41 肽和低亲和力抗 HIV 抗体的结合，使 gp41 肽 p57 适合区分近期和长期的 HIV-1 感染。此外，基于 MP3 或 MP4 的免疫测定可以显著提高检测的敏感性，并在横断面和纵向样本中分别显示与商业 LAg-Avidity EIA 检测的 93.33%（140/150）与 94.59%（35/37）和 94.08%（143/152）与 94.59%（35/37）的一致性。近期感染的估计平均持续时间 (MDRI) 分别为 130 天（95%CI：83-167）和 166 天（95%CI：123-202），用于 MP3 和 MP4 检测。我们的初步结果表明，针对主要 HIV-1 基因型 CRF01_AE、CRF07_BC/CRF08_BC 和亚型 B 的 HIV-1 gp41 肽基免疫测定可以作为一种简单的发病率检测方法，用于区分中国近期和长期的 HIV-1 感染。
