预测最近的HIV-1感染使用香农 entropy 分析的HIV-1群体特异抗原蛋白序列
Tumelo L Fortuin1, Paballo Nkone1, Shayne Loubser2
1Department of Medical Virology, University of Pretoria, Private Bag X323, Gezina, 0002, South Africa.
Virology journal
|February 3, 2026
概括
对HIV-1的Gag序列的Shannon entropy分析可以帮助识别最近的感染. 虽然这种分子策略很有前途,但高错误最近率需要谨慎和进一步研究以提高准确性.
科学领域:
- 病毒学 病毒学
- 分子生物学分子生物学
- 流行病学 流行病学
背景情况:
- 贪性测试经常错误地将慢性HIV-1感染归类为最近的,特别是在接受抗逆转录病毒疗法的人群中,导致流行病学数据不准确.
- 挑战在于区分最近的人类免疫缺陷病毒1型 (HIV-1) 感染与慢性感染,特别是治疗干预措施.
- 准确识别最近的HIV-1感染对于有效的公共卫生监测和干预策略至关重要.
研究的目的:
- 评估香农的实用性,以评估HIV-1特定组抗原 (Gag) 序列多样性,以预测最近的HIV-1感染.
- 为了确定HIV-1Gag序列中的特定氨基酸 (aa) 位点,这些位点显示了最近和慢性感染之间的差异性突变模式.
- 评估基于Gag的分子策略在检测最近的HIV-1感染及其相关的错误新发率 (FRR) 中的性能.
主要方法:
- 从参与者确认最近或慢性HIV-1感染的桑格序列的回顾性分析.
- 对于完整的HIV-1 Gag氨基酸 (aa) 序列 (501aa) 的Shannon的计算和滑窗分析.
- 鉴定近期和慢性阶段之间具有明显突变分布的aa位点,根据参考序列进行验证.
主要成果:
- 与最近感染相比,慢性HIV-1感染中观察到明显更高的aa多样性 (p=0.0003).
- 四个aa位 (S54,E55,I256,S451) 显示差异分布模式,其中三个达到统计学意义.
- 分子策略实现了71-86%的检测,但呈现出高FRR (39%-52%),在结合信息网站时,该FRR降至24%以下.
结论:
- 基于Gag的分子策略利用序列多样性可以帮助检测最近的HIV-1感染,其中Gag序列可用.
- 目前的方法需要谨慎的解释,因为它与高的虚假近期率有显著的关联.
- 进一步的研究是必不可少的,以开发更准确的分子策略来检测最近的HIV-1感染,以提高性能.
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