The Lyme disease agent, @entity2069 , is able to persistently infect @entity1 and animals for months or years in the presence of an active immune response. It is not known how the organisms survive immune attack in the @entity1 host. vlsE, a gene localized near one end of linear plasmid lp28-1 and encoding a surface-exposed lipoprotein in @entity31350 , was shown recently to undergo extensive genetic and antigenic variation within 28 days of @entity281 in C3H/HeN @entity19 . In this study, we examined the kinetics of vlsE sequence variation in C3H/HeN @entity19 at 4, 7, 14, 21, and 28 days and at 7 and 12 months postinfection. Sequence changes were detected by PCR amplification and sequence analysis as early as 4 days postinfection and accumulated progressively in both C3H/HeN and CB-17 @entity466 ( @entity466 ) @entity19 throughout the course of @entity281 . The sequence changes were consistent with sequential recombination of segments from multiple silent vls cassette sites into the vlsE expression site. No vlsE sequence changes were detected in organisms cultured in vitro for up to 84 days. These results indicate that vlsE recombination is induced by a factor(s) present in the @entity1 host, independent of adaptive immune responses. The possible inducing conditions appear to be present in various tissue sites because isolates from multiple tissues showed similar degrees of sequence variation. The rate of accumulation of predicted @entity535 changes was higher in the immunologically intact C3H/HeN @entity19 than in @entity466 @entity19 , a finding consistent with immune selection of VlsE variants.

Kinetics and in vivo induction of genetic variation of vlsE in XXXX .

@entity1 :: ('9606', 'Species') :: ['mammalian', 'humans'] @entity19 :: ('10090', 'Species') :: ['mice'] @entity535 :: ('CHEBI:33704', 'Chemical') :: ['amino acid'] @entity2069 :: ('139', 'Species') :: ['Borrelia burgdorferi'] @entity281 :: ('MESH:D007239', 'Disease') :: ['infection', 'initial infection'] @entity31350 :: ('224326', 'Species') :: ['B. burgdorferi B31'] @entity466 :: ('MESH:D016511', 'Disease') :: ['SCID', 'severe combined immunodeficient']
@entity2069 :: (139,Species) :: ['Borrelia burgdorferi']
