Please use this identifier to cite or link to this item: https://www.arca.fiocruz.br/handle/icict/15244
Title: Acquisition of negative complement regulators by the saprophyte Leptospira biflexa expressing LigA or LigB confers enhanced survival in human serum
Authors: Castiblanco-Valencia, Mónica M
Fraga, Tatiana Rodrigues
Breda, Leandro Carvalho Dantas
Vasconcellos, Sílvio Arruda
Figueira, Cláudio Pereira
Picardeau, Mathieu
Wunder, Elsio
Ko, Albert Icksang
Barbosa, Angela Silva
Isaac, Lourdes
Affilliation: University of São Paulo. Institute of Biomedical Sciences. Department of Immunology. São Paulo, SP, Brasil
University of São Paulo. Institute of Biomedical Sciences. Department of Immunology. São Paulo, SP, Brasil
University of São Paulo. Institute of Biomedical Sciences. Department of Immunology. São Paulo, SP, Brasil
University of São Paulo. Faculty of Veterinary Medicine. São Paulo, SP, Brasil
Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil
Institut Pasteur. Biology of Spirochetes Unit. Paris, Francee
Yale University. Department of Epidemiology of Microbial Diseases. USA
Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil / Yale University. Department of Epidemiology of Microbial Diseases. USA
Butantan Institute. Laboratory of Bacteriology. São Paulo, SP, Brasil
University of São Paulo. Institute of Biomedical Sciences. Department of Immunology. São Paulo, SP, Brasil
Abstract: Leptospiral immunoglobulin-like (Lig) proteins are surface exposed molecules present in pathogenic but not in saprophytic Leptospira species. We have previously shown that Lig proteins interact with the soluble complement regulators Factor H (FH), FH like-1 (FHL-1), FH related-1 (FHR-1) and C4b Binding Protein (C4BP). In this study, we used the saprophyte L. biflexa serovar Patoc as a surrogate host to address the specific role of LigA and LigB proteins in leptospiral complement evasion. L. biflexa expressing LigA or LigB was able to acquire FH and C4BP. Bound complement regulators retained their cofactor activities of FI in the proteolytic cleavage of C3b and C4b. Moreover, heterologous expression of ligA and ligB genes in the saprophyte L. biflexa enhanced bacterial survival in human serum. Complement deposition on lig-transformed L. biflexa was assessed by flow cytometry analysis. With regard to MAC deposition, L. biflexa expressing LigA or LigB presented an intermediate profile: MAC deposition levels were greater than those found in the pathogenic L. interrogans, but lower than those observed for L. biflexa wildtype. In conclusion, Lig proteins contribute to in vitro control of complement activation on the leptospiral surface, promoting an increased bacterial survival in human serum.
Keywords: Leptospira
Complement
Immune evasion
Lig proteins
Factor H
C4BP
Issue Date: 2016
Publisher: Elsevier
Citation: CASTIBLANCO-VALENCIA, M. M. et al. Acquisition of negative complement regulators by the saprophyte Leptospira biflexa expressing LigA or LigB confers enhanced survival in human serum. Immunology Letters, v. 173, p. 61–68, 2016.
DOI: 10.1016/j.imlet.2016.03.005
ISSN: 0165-2478
Copyright: open access
Appears in Collections:BA - IGM - Artigos de Periódicos

Files in This Item:
File Description SizeFormat 
Valencia MMC Acquisition of negative.pdf2.15 MBAdobe PDFView/Open


FacebookTwitterDeliciousLinkedInGoogle BookmarksBibTex Format mendeley Endnote DiggMySpace

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.