Open AccessAntigenicity and recombination of VlsE, the antigenic variation protein of Borrelia burgdorferi , in rabbits, a host putatively resistant to long‐term infection with this spirochete
Author(s) -
Embers Monica E.,
Liang Fang Ting,
Howell Jerrilyn K.,
Jacobs Mary B.,
Purcell Jeanette E.,
Norris Steven J.,
Johnson Barbara J. B.,
Philipp Mario T.
Publication year - 2007
Publication title -
fems immunology & medical microbiology
Language(s) - English
Resource type - Journals
eISSN - 1574-695X
pISSN - 0928-8244
DOI - 10.1111/j.1574-695x.2007.00276.x
Subject(s) - borrelia burgdorferi , biology , antigenicity , antigenic variation , lyme disease , borrelia , spirochaetaceae , antigen , antibody , microbiology and biotechnology , virology , immune system , flagellin , epitope , pathogen , immunology , genetics , bacteria
Borrelia burgdorferi , the Lyme disease pathogen, employs several immune‐evasive strategies to survive in mammals. Unlike mice, major reservoir hosts for B. burgdorferi , rabbits are considered to be nonpermissive hosts for persistent infection. Antigenic variation of the VlsE molecule is a probable evasion strategy known to function in mice. The invariable region 6 (IR6) and carboxyl‐terminal domain (Ct) of VlsE elicit dominant antibody responses that are not protective, perhaps to function as decoy epitopes that protect the spirochete. We sought to determine if either of these characteristics of VlsE differed in rabbit infection, contributing to its reputed nonpermissiveness. VlsE recombination was observed in rabbits that were given inoculations with either cultured or host‐adapted spirochetes. Early observations showed a lack of anti‐C6 (a peptide encompassing the IR6 region) response in most rabbits, so the anti‐Ct and anti‐C6 responses were monitored for 98 weeks. Anti‐C6 antibody appeared as late as 20 weeks postinoculation, and the anti‐Ct response, evident within the first 2 weeks, oscillated for prolonged periods of time. These observations, together with the recovery of cultivable spirochetes from tissue of one animal at 98 weeks postinoculation, challenge the notion that the rabbit cannot harbour a long‐term B. burgdorferi infection.