TY - JOUR A1 - Burgel, Nathalie D. van A1 - Kraiczy, Peter A1 - Schuijt, Tim J. A1 - Zipfel, Peter F. A1 - Dam, Alje P. van T1 - Identification and functional characterisation of Complement Regulator Acquiring Surface Protein-1 of serum resistant Borrelia garinii OspA serotype 4 T2 - BMC microbiology N2 - Background: B. burgdorferi sensu lato (sl) is the etiological agent of Lyme borreliosis in humans. Spirochetes have adapted themselves to the human immune system in many distinct ways. One important immune escape mechanism for evading complement activation is the binding of complement regulators Factor H (CFH) or Factor H-like protein1 (FHL-1) to Complement Regulator-Acquiring Surface Proteins (CRASPs). Results: We demonstrate that B. garinii OspA serotype (ST4) PBi resist complement-mediated killing by binding of FHL-1. To identify the primary ligands of FHL-1 four CspA orthologs from B. garinii ST4 PBi were cloned and tested for binding to human CFH and FHL-1. Orthologs BGA66 and BGA71 were found to be able to bind both complement regulators but with different intensities. In addition, all CspA orthologs were tested for binding to mammalian and avian CFH. Distinct orthologs were able to bind to CFH of different animal origins. Conclusions: B. garinii ST4 PBi is able to evade complement killing and can bind FHL-1 to membrane expressed proteins. Recombinant proteins BGA66 can bind FHL-1 and human CFH, while BGA71 can bind only FHL-1. All recombinant CspA orthologs from B. garinii ST4 PBi can bind CFH from different animal origins. This partly explains the wide variety of animals that can be infected by B. garinii. KW - Lyme Borreliosis KW - Membrane Attack Complex KW - Complement Regulator KW - Borrelia Garinii KW - Serum Susceptibility Y1 - 2010 UR - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/7592 UR - https://nbn-resolving.org/urn:nbn:de:hebis:30-75009 SN - 1471-2180 N1 - © 2010 van Burgel et al., licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. VL - 10 IS - Art. 43 SP - 1 EP - 12 PB - BioMed Central ; Springer CY - London ; Berlin ; Heidelberg ER -