Department of Laboratory Medicine, Jingzhou Hospital Affiliated to Yangtze University, Jingzhou, 434020, China.
Virol J. 2024 Jul 5;21(1):152. doi: 10.1186/s12985-024-02424-9.
High-risk human papillomavirus (HR-HPV) infection is an important factor for the development of cervical cancer. HPV18 is the second most common HR-HPV after HPV16.
In this study, MEGA11 software was used to analyze the variation and phylogenetic tree of HPV18 E6-E7 and L1 genes. The selective pressure to E6, E7 and L1 genes was estimated using pamlX. In addition, the B cell epitopes of L1 amino acid sequences and T cell epitopes of E6-E7 amino acid sequences in HPV18 were predicted by ABCpred server and IEDB website, respectively.
A total of 9 single nucleotide variants were found in E6-E7 sequences, of which 2 were nonsynonymous variants and 7 were synonymous variants. Twenty single nucleotide variants were identified in L1 sequence, including 11 nonsynonymous variants and 9 synonymous variants. Phylogenetic analysis showed that E6-E7 and L1 sequences were all distributed in A lineage. In HPV18 E6, E7 and L1 sequences, no positively selected site was found. The nonconservative substitution R545C in L1 affected hypothetical B cell epitope. Two nonconservative substitutions, S82A in E6, and R53Q in E7, impacted multiple hypothetical T cell epitopes.
The sequence variation data of HPV18 may lay a foundation for the virus diagnosis, further study of cervical cancer and vaccine design in central China.
高危型人乳头瘤病毒（HR-HPV）感染是宫颈癌发展的重要因素。HPV18 是继 HPV16 之后第二常见的 HR-HPV。
本研究使用 MEGA11 软件分析 HPV18 E6-E7 和 L1 基因的变异和系统进化树。使用 pamlX 估计 E6、E7 和 L1 基因的选择压力。此外，通过 ABCpred 服务器和 IEDB 网站分别预测 HPV18 L1 氨基酸序列的 B 细胞表位和 E6-E7 氨基酸序列的 T 细胞表位。
E6-E7 序列中发现了 9 个单核苷酸变异，其中 2 个为非同义变异，7 个为同义变异。L1 序列中鉴定出 20 个单核苷酸变异，包括 11 个非同义变异和 9 个同义变异。系统进化分析显示，E6-E7 和 L1 序列均分布在 A 谱系中。HPV18 E6、E7 和 L1 序列中未发现正选择位点。L1 中的非保守性取代 R545C 影响假设的 B 细胞表位。E6 中的 S82A 和 E7 中的 R53Q 两个非保守性取代影响多个假设的 T 细胞表位。
HPV18 的序列变异数据可能为病毒诊断、进一步研究中国中部地区宫颈癌和疫苗设计奠定基础。
