scholarly journals Tick-Borne Relapsing Fever in British Columbia, Canada: First Isolation of Borrelia hermsii

1998 ◽  
Vol 36 (12) ◽  
pp. 3505-3508 ◽  
Author(s):  
Satyendra N. Banerjee ◽  
Maya Banerjee ◽  
Keerthi Fernando ◽  
Willy Burgdorfer ◽  
Tom G. Schwan
Keyword(s):  
Monoclonal Antibody ◽  
British Columbia ◽  
Plasmid Dna ◽  
Geographic Area ◽  
Protein Profiles ◽  
Specific Monoclonal Antibody ◽  
Relapsing Fever ◽  
Borrelia Hermsii ◽  
First Case ◽  
Species Specific

The spirochete that causes tick-borne relapsing fever,Borrelia hermsii, was isolated in pure culture during 1995 and 1996 from three acutely ill human patients infected in southern British Columbia, Canada. The geographic area of exposure is a known focus of this disease dating back to 1930 when the first case was recognized in a human. Analyses of plasmid DNA, protein profiles, and reactivity with a species-specific monoclonal antibody identified the new isolates of spirochetes as B. hermsii, all of which were most similar to an isolate of this spirochete from northern California described previously. These are the first reported isolates of B. hermsii from Canada.

scholarly journals Immunological and Molecular Analyses of the Borrelia hermsii Factor H and Factor H-Like Protein 1 Binding Protein, FhbA: Demonstration of Its Utility as a Diagnostic Marker and Epidemiological Tool for Tick-Borne Relapsing Fever

2006 ◽  
Vol 74 (8) ◽  
pp. 4519-4529 ◽  
Author(s):  
Kelley M. Hovis ◽  
Martin E. Schriefer ◽  
Sonia Bahlani ◽  
Richard T. Marconi
Keyword(s):  
Binding Protein ◽  
Pcr Primers ◽  
Factor H ◽  
Antigenic Structure ◽  
Diagnostic Tools ◽  
Relapsing Fever ◽  
Borrelia Hermsii ◽  
Specific Pcr ◽  
Epidemiological Tool ◽  
Species Specific

ABSTRACT It has been demonstrated that Borrelia hermsii, a causative agent of relapsing fever, produces a factor H (FH) and FH-like protein 1 (FHL-1) binding protein. The binding protein has been designated FhbA. To determine if FH/FHL-1 binding is widespread among B. hermsii isolates, a diverse panel of strains was tested for the FH/FHL-1 binding phenotype and FhbA production. Most isolates (23/24) produced FhbA and bound FH/FHL-1. Potential variation in FhbA among isolates was analyzed by DNA sequence analyses. Two genetically distinct FhbA types, designated fhbA1 and fhbA2, were delineated, and type-specific PCR primers were generated to allow for rapid differentiation. Pulsed-field gel electrophoresis and hybridization analyses demonstrated that all isolates that possess the gene carry it on a 200-kb linear plasmid (lp200), whereas isolates that lack the gene lack lp200 and instead carry an lp170. To determine if FhbA is antigenic during infection and to assess the specificity of the response, recombinant FhbA1 (rFhbA1) and rFhbA2 were screened with serum from infected mice and humans. FhbA was found to be expressed and antigenic and to elicit a potentially type-specific FhbA response. To localize the epitopes of FhbA1 and FhbA2, truncations were generated and screened with infection serum. The epitopes were determined to be conformationally defined. Collectively, these analyses indicate that FH/FHL-1 binding is a widespread virulence mechanism for B. hermsii and provide insight into the genetic and antigenic structure of FhbA. The data also have potential implications for understanding the epidemiology of relapsing fever in North America and can be applied to the future development of species-specific diagnostic tools.

scholarly journals Chlamydia pneumoniae Major Outer Membrane Protein Is a Surface-Exposed Antigen That Elicits Antibodies Primarily Directed against Conformation-Dependent Determinants

2001 ◽  
Vol 69 (5) ◽  
pp. 3082-3091 ◽  
Author(s):  
Katerina Wolf ◽  
Elizabeth Fischer ◽  
David Mead ◽  
Guangming Zhong ◽  
Roseanna Peeling ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Membrane Protein ◽  
Outer Membrane ◽  
Outer Membrane Protein ◽  
Chlamydia Pneumoniae ◽  
Major Outer Membrane Protein ◽  
Mass Spectrometry Analysis ◽  
Antigenic Determinants ◽  
Specific Monoclonal Antibody ◽  
Species Specific

ABSTRACT The major outer membrane protein (MOMP) of Chlamydia trachomatis serovariants is known to be an immunodominant surface antigen. Moreover, it is known that the C. trachomatis MOMP elicits antibodies that recognize both linear and conformational antigenic determinants. In contrast, it has been reported that the MOMP of Chlamydia pneumoniae is not surface exposed and is immunorecessive. We hypothesized that the discrepancies betweenC. trachomatis and C. pneumoniae MOMP exposure on intact chlamydiae and immunogenic properties might be because the focus of the host's immune response is directed to conformational epitopes of the C. pneumoniae MOMP. We therefore conducted studies aimed at defining the surface exposure of MOMP and the conformational dominance of MOMP antibodies. We present here a description of C. pneumoniaespecies-specific monoclonal antibody (MAb), GZD1E8, which recognizes a conformational epitope on the surface of C. pneumoniae. This MAb is potent in the neutralization ofC. pneumoniae infectivity in vitro. Another previously described C. pneumoniaespecies-specific monoclonal antibody, RR-402, displayed very similar characteristics. However, the antigenic determinant recognized by RR-402 has yet to be identified. We show by immunoprecipitation ofC. pneumoniae with GZD1E8 and RR-402 MAbs and by mass spectrometry analysis of immunoprecipitated proteins that both antibodies GZD1E8 and RR-402 recognize the MOMP of C. pneumoniae and that this protein is localized on the surface of the organism. We also show that human sera fromC. pneumoniae-positive donors consistently recognize the MOMP by immunoprecipitation, indicating that the MOMP ofC. pneumoniae is an immunogenic protein. These findings have potential implications for both C. pneumoniae vaccine and diagnostic assay development.

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