Factor H facilitates adherence of Neisseria gonorrhoeae to complement receptor 3 on eukaryotic cells

摘要: Neisseria gonorrhoeae can engage human complement receptor 3 (CR3) directly or through surface-bound iC3b. Factor H (fH) that binds to bacteria facilitates conversion of C3b fH also CR3 on professional phagocytes. Certain nonprofessional phagocytes, such as primary cervical epithelial cells, express CR3. We hypothesized could bridge and facilitate gonococcal association with host cells. Specificity the fH-CR3 interaction was confirmed using CR3-transfected Chinese hamster ovary (CHO-CR3) Using recombinant proteins comprised contiguous domains (fH contains 20 short consensus repeat [SCR] domains) fused murine Fc, we observed strong binding SCRs 18-20, whereas weaker occurred 6-10. Both regions bound unsialylated porin (Por) B.1A-expressing N. gonorrhoeae. Accordingly, fH-related protein 1 (three its five are highly homologous 18-20) CHO-CR3 PorB.1A gonococci. An alternatively spliced variant called fH-like protein-1 (contains 1-7) gonococci but minimally CHO-CR3. 6-20 construct enhanced However, a contained only apparently relevant (6, 7, separately, did not enhance bacteria-CR3 interactions, suggesting intervening (8-17) may impart configurational spatial requirement for These results indicate adherence between fH-coated provide means gain sanctuary into