Suppr超能文献

肺炎链球菌结合宿主细胞死亡时的 GAPDH 加剧流感后继发感染

Streptococcus pneumoniae binds to host GAPDH on dying lung epithelial cells worsening secondary infection following influenza.

机构信息

Department of Microbiology, The University of Alabama at Birmingham, Birmingham, AL, USA.

Infectious Diseases and Genomic Medicine Group, J. Craig Venter Institute, Rockville, MD, USA.

出版信息

Cell Rep. 2021 Jun 15;35(11):109267. doi: 10.1016/j.celrep.2021.109267.

Abstract

Streptococcus pneumoniae (Spn) alone and during co-infection with influenza A virus (IAV) can result in severe pneumonia with mortality. Pneumococcal surface protein A (PspA) is an established virulence factor required for Spn evasion of lactoferricin and C-reactive protein-activated complement-mediated killing. Herein, we show that PspA functions as an adhesin to dying host cells. We demonstrate that PspA binds to host-derived glyceraldehyde-3-phosphate dehydrogenase (GAPDH) bound to outward-flipped phosphatidylserine residues on dying host cells. PspA-mediated adhesion was to apoptotic, pyroptotic, and necroptotic cells, but not healthy lung cells. Using isogenic mutants of Spn, we show that PspA-GAPDH-mediated binding to lung cells increases pneumococcal localization in the lower airway, and this is enhanced as a result of pneumolysin exposure or co-infection with IAV. PspA-mediated binding to GAPDH requires amino acids 230-281 in its α-helical domain with intratracheal inoculation of this PspA fragment alongside the bacteria reducing disease severity in an IAV/Spn pneumonia model.

摘要

肺炎链球菌(Spn)单独感染或与甲型流感病毒(IAV)共同感染可导致严重肺炎和死亡率。肺炎球菌表面蛋白 A(PspA)是一种已被证实的毒力因子,可使 Spn 逃避乳铁蛋白和 C 反应蛋白激活的补体介导的杀伤。在此,我们发现 PspA 可作为一种黏附素作用于濒死宿主细胞。我们证明 PspA 可与宿主来源的甘油醛-3-磷酸脱氢酶(GAPDH)结合,而 GAPDH 结合在濒死宿主细胞外翻的磷脂酰丝氨酸残基上。PspA 介导的黏附作用于凋亡、细胞焦亡和坏死细胞,但不作用于健康的肺细胞。通过 Spn 的同工型突变体,我们发现 PspA-GAPDH 介导的与肺细胞的结合增加了肺炎链球菌在下呼吸道的定位,并且这种结合由于肺炎球菌溶素的暴露或与 IAV 的共同感染而增强。PspA 与 GAPDH 的结合需要其α螺旋结构域中的 230-281 个氨基酸,通过气管内接种该 PspA 片段以及细菌,可以降低 IAV/Spn 肺炎模型的疾病严重程度。

https://cdn.ncbi.nlm.nih.gov/pmc/blobs/77aa/8265312/d140bef4f8a8/nihms-1715706-f0001.jpg

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍。

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索

文档翻译

学术文献翻译模型,支持多种主流文档格式。

立即体验