In vivo binding of complement regulator factor H by Streptococcus pneumoniae.
In vivo binding of complement regulator factor H by Streptococcus pneumoniae.
复制标题
肺炎链球菌体内补体调节因子 H 的结合。
DOI：
10.1086/497605
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
McDaniel,LarryS
中科院分区：
文献类型：
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作者：
Quin,LisaR;Carmicle,Stephanie;Dave,Sandhya;Pangburn,MichaelK;Evenhuis,JasonP;McDaniel,LarryS
肺炎球菌表面蛋白C （PspC）与补体调节蛋白因子H （FH）结合，抑制替代途径的激活。在本研究中，使用小鼠全身感染模型和流式细胞术分析，我们证明了FH和肺炎球菌之间的体内相互作用，并在菌血症期间显示了FH结合的差异。腹腔（ip）攻击后收获的肺炎球菌的流式细胞分析显示，与静脉（iv）攻击后相比，FH的结合增加。PspC mRNA的实时聚合酶链反应分析显示，与体外培养的肺炎球菌相比，静脉注射24小时后从小鼠血液中回收的PspC mRNA水平高出23倍；而ip刺激后，PspC mRNA诱导量增加870倍。使用抗PspC的单克隆抗体，流式细胞术检测到PspC表达的随后增加。此外，与未使用FH预处理的肺炎球菌相比，暴露前与FH结合补体的肺炎球菌增殖增加。这些结果表明，PspC和FH之间的相互作用有助于肺炎球菌的毒力
Pneumococcal surface protein C (PspC) binds to the complement regulatory protein factor H (FH), which inhibits alternative pathway activation. In the present study, using a mouse model of systemic infection and flow-cytometric analyses, we demonstrated an in vivo interaction between FH and pneumococci and showed differential FH binding during bacteremia. Flow-cytometric analyses of pneumococci harvested after intraperitoneal (ip) challenge demonstrated increased binding of FH, compared with that after intravenous (iv) challenge. Real-time polymerase chain reaction analyses of PspC mRNA showed that, relative to pneumococci grown in vitro, those recovered from the blood of mice 24 h after iv challenge exhibited 23-fold higher mRNA levels; however, after ip challenge, PspC mRNA induction was increased 870-fold. A subsequent increase in PspC expression was detected by flow cytometry using a monoclonal antibody against PspC. Furthermore, pneumococci with FH bound to complement before exposure had increased proliferation, compared with pneumococci not pretreated with FH. These results suggest that the interaction between PspC and FH contributes to pneumococcal virulence