Identification and functional characterisation of Complement Regulator Acquiring

February 21, 2010

Identification and functional characterisation of

Complement Regulator Acquiring,Surface Protein-1 of serum

resistant Borrelia garinii OspA serotype 4.

BMC Microbiol. 2010 Feb 10;10(1):43 [Epub ahead of print]

Identification and functional characterisation of Complement

Regulator Acquiring Surface Protein-1 of serum resistant Borrelia

garinii OspA serotype 4.

van Burgel ND, Kraiczy P, Schuijt TJ, Zipfel PF, van Dam AP.

ABSTRACT: 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.

bmed & id=20146822 & retmode=ref & cmd=prlinks

PMID: 20146822 [PubMed - as supplied by publisher]

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