德尔塔和卡帕SARS-CoV-2变种免疫逃避的分子基础
Matthew McCallum1, Alexandra C Walls1, Kaitlin R Sprouse1
1Department of Biochemistry, University of Washington, Seattle, WA 98195, USA.
概括
新型严重急性呼吸综合征冠状病毒2 (SARS-CoV-2) 变种,如德尔塔病毒,避开疫苗抗体,影响它们的中和作用. 这些变种的结构变化解释了它们的免疫逃避机制.
科学领域:
- 病毒学
- 免疫学
- 结构生物学
背景情况:
- 严重急性呼吸道综合征冠状病毒2 (SARS-CoV-2) 传播推动了新变种的演变.
- B.1.617.2 (三角洲) 变种已成为全球占主导地位的变种,导致广泛的感染.
- 对于公共卫生策略来说,了解变异性免疫规避至关重要.
研究的目的:
- 调查SARS-CoV-2变种对疫苗引起的中和抗体的影响.
- 为变种的免疫逃避机制提供结构基础.
- 分析变异性尖端蛋白与血管酶转化酶2 (ACE2) 的结合亲和力.
主要方法:
- 在实验室中评估疫苗引起的针对SARS-CoV-2变种的血清中和抗体效力.
- 来自B.1.617.1 (卡帕) 和Delta变种的尖端糖蛋白的结构分析.
- 确定卡帕和德尔塔变异的受体结合域的ACE2结合亲缘关系.
主要成果:
- 包括德尔塔在内的SARS-CoV-2变种降低了疫苗引起的中和抗体的体外活性.
- 在Kappa和Delta尖端糖蛋白中发生的突变改变了抗原位,阻碍了单克隆抗体的识别.
- 德尔塔变种表现出其氨基终端域的重塑,导致免疫逃避.
- 卡帕和德尔塔受体结合域与武汉- 胡-1 分离物具有可比的ACE2 结合亲缘关系.
- 德尔塔+ 变种显示显著降低了ACE2 的结合亲和力.
结论:
- 新出现的SARS-CoV-2变种具有免疫逃避能力,降低了疫苗诱导的抗体的有效性.
- 变异性尖端蛋白的结构变化是它们免疫逃避的关键决定因素.
- 了解这些结构和功能变化对于开发下一代疫苗和治疗方法至关重要.
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