通过H因子保护Trypanosoma cruzi从补充的替代途径的机制
Smrithi S Menon1, Galia Ramirez-Toloza2, Keith L Wycoff3
1Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, OH, United States.
Frontiers in immunology
|February 16, 2024
概括
查加斯病寄生虫Trypanosoma cruzi通过结合因子H来逃避免疫攻击.这种结合,由特定的寄生虫表面分子介导,增强了寄生虫在宿主中的生存.
科学领域:
- 免疫学 免疫学 免疫学
- 寄生虫学的寄生虫学
- 分子生物学分子生物学
背景情况:
- 查加斯病是由Trypanosoma cruzi引起的,没有有效的治疗或疫苗.
- 传染性tripomastigote形式的T. cruzi抵抗补充介导杀戮.
- H因子 (FH) 调节补充替代途径 (AP),并被病原体用来逃避免疫反应.
研究的目的:
- 为了阐明H因子与Trypanosoma cruzi结合的分子基础.
- 确定H因子在T. cruzi trypomastigotes补充抵抗中的作用.
主要方法:
- 研究了FH与T. cruzi的直接结合,包括typomastigotes和epimastigotes.
- 使用FH片段和FH-Fc融合蛋白的域映射.
- 使用FH相关的蛋白-5来抑制FH结合并评估寄生虫的存活率.
主要成果:
- 虽然T. cruzi是typomastigotes,但不是epimastigotes,它们直接与FH结合,而不依赖于C3沉积.
- FH 域 5-8 部分抑制了 FH 与体结合的结合,而不会影响补体抵抗.
- 与FH相关的蛋白-5完全抑制了FH结合,并且在血清中显著降低了tripomastigote存活率.
结论:
- 与T. cruzi trypomastigotes结合的H因子对于补充电阻至关重要.
- 特定的寄生虫表面相互作用介导FH结合,独立于补充物opsonization.
- 针对FH-寄生虫相互作用提供了对查加斯病的潜在策略.
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