Pathogenic Leptospira species acquire factor H and vitronectin via the surface protein LcpA

da Silva, LB; Miragaia, L; Breda, LC; Abe, CM; Schmidt, MC; Moro, AM; Monaris, D; Conde, JN; Józsi, M; Isaac, L; Abreu, PA; Barbosa, AS

HERO ID

2902375

Reference Type

Journal Article

Year

2015

Language

English

PMID

25534939

HERO ID 2902375
In Press No
Year 2015
Title Pathogenic Leptospira species acquire factor H and vitronectin via the surface protein LcpA
Authors da Silva, LB; Miragaia, L; Breda, LC; Abe, CM; Schmidt, MC; Moro, AM; Monaris, D; Conde, JN; Józsi, M; Isaac, L; Abreu, PA; Barbosa, AS
Journal Infection and Immunity
Volume 83
Issue 3
Page Numbers 888-897
Abstract Upon infection, pathogenic Leptospira species bind several complement regulators in order to overcome host innate immunity. We previously characterized a 20-kDa leptospiral surface protein which interacts with C4b binding protein (C4BP): leptospiral complement regulator-acquiring protein A (LcpA). Here we show that LcpA also interacts with human factor H (FH), which remains functionally active once bound to the protein. Antibodies directed against short consensus repeat 20 (SCR20) inhibited binding of FH to LcpA by approximately 90%, thus confirming that this particular domain is involved in the interaction. We have also shown for the first time that leptospires bind human vitronectin and that the interaction is mediated by LcpA. Coincubation with heparin blocked LcpA-vitronectin interaction in a dose-dependent manner, strongly suggesting that binding may occur through the heparin binding domains of vitronectin. LcpA also bound to the terminal pathway component C9 and inhibited Zn(2+)-induced polymerization and membrane attack complex (MAC) formation. Competitive binding assays indicated that LcpA interacts with C4BP, FH, and vitronectin through distinct sites. Taken together, our findings indicate that LcpA may play a role in leptospiral immune evasion.
Doi 10.1128/IAI.02844-14
Pmid 25534939
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English