突变使可消耗碳水化合物抗原的生物合成不活化,防止了灵长类动物/人类血统进化中的灭绝
1Rush University Medical Center, 910 South Michigan Avenue, Apt. 904, Chicago, IL, 60605, USA. uri.galili@rcn.com.
Journal of molecular evolution
|March 30, 2025
概括
人类天然抗体如抗Gal,抗Neu5Gc和抗Forssman在早期猿类中出现. 这些抗体保护了突变后代免受致命病毒的侵袭,可能推动了进化选择.
科学领域:
- 进化免疫学的进化免疫学
- 糖甘生物学的生物学
- 哺乳动物进化 哺乳动物进化
背景情况:
- 天然抗体抗Gal,抗Neu5Gc和抗Forssman是古老的进化遗留物,在猿类和原始人类中发现.
- 这些抗体发生在突变后代中,后者丧失了合成特定碳水化合物抗原 (α-gal, Neu5Gc, Forssman) 的能力.
- 环境抗原,如来自人类微生物群的抗原,可以刺激抗体的产生.
研究的目的:
- 介绍一种替代的选择性机制,用于进化消除哺乳动物中可用的碳水化合物抗原.
- 将自然抗体 (抗Gal,抗Neu5Gc,抗Forssman) 的分布与保护作用联系起来.
- 探索这些抗体在保护动物性病毒感染中的作用.
主要方法:
- 对自然抗体分布和进化选择性压力的现有文献的审查.
- 对碳水化合物抗原消除的拟议机制的分析,包括病毒对接和抗体介导保护.
- 综合证据,将天然抗体与针对呈现特定碳水化合物抗原的病毒的保护联系起来.
主要成果:
- 一个替代假设表明,致命的包裹病毒的流行病导致了合成特定碳水化合物抗原的父母种群的灭绝.
- 缺少这些抗原的突变后代受到与病毒碳水化合物抗原结合的天然抗体的保护.
- 最近的研究表明,这些抗体继续保护人类免受涉及α-gal,Neu5Gc或Forssman抗原的动物感染.
结论:
- 自然抗体在哺乳动物进化中发挥了关键作用,通过保护人类免受致命的病毒流行病.
- 抗Gal,抗Neu5Gc和抗Forssman抗体的存在与保护有关,而不仅仅是与病毒对接有关.
- 这些抗体对人类免疫力对新兴动物性病毒威胁的免疫力至关重要.
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