Variable major proteins of Borrellia hermsii.

A G Barbour,S L Tessier,H G Stoenner

doi:10.1084/jem.156.5.1312

Abstract

Borrelia hermsii, a relapsing fever agent, manifests antigenic variation in vivo and in vitro. We studied three mouse-passaged serotypes of strain HS1 (7, 14, and 21) and a HS1 derivative obtained after multiple in vitro passages (C serotype). All four serotypes had two major proteins in whole cell lysates fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. One major protein species (pII) had the same apparent subunit molecular weight (or approximately 3.9 X 10(4) in all the serotypes. In contrast, the other abundant protein in lysates, pI, had a different apparent molecular weight in each serotype. In one gel the molecular weights of pIc, pI7, pI14, and pI21 were 1.9, 4.2, 4.1, and 4.0 X 10(4), respectively. Serotype-specific mouse antisera bound to both hemologous and heterologous pIIs, to homologous pI, but not to heterologous pI in Western blots. Hybridomas were raised from spleens of mice infected with B. hermsii. Monoclonal antibodies were identified by immunofluorescence assays using whole organisms. Monoclonal antibodies specific for serotype 7 (H1826) or for serotype 21 (H3326) bound only to pI7 or pI21, respectively, in Western blots. The surface location of the pI was suggested not only by the immunofluorescence studies but also by the labeling of pI7 and pI21 when whole cells of serotypes 7 and 21 were incubated with 125I in the presence of Iodogen. Under the same circumstances, pII was relatively poorly labeled. These studies have identified the variable pI proteins of B. hermsii as serotype-specific antigens. A change from one pI to another may be the basis of antigenic variation of Borrelia species during relapsing fever.

Highlights

The reappearance of borreliae in a patient's blood during a second, third, or fourth febrile crisis of relapsing fever has suggested to students of this disease that these spirochetes undergo antigenic variation [1,2,3,4]
Using both polyclonal antisera and monoclonal antibodies, we have identified in whole cell lysates of B. hermsii an abundant protein that is serotype specific
HS1 was cloned by limiting dilution in Swiss mice of the Rocky Mountain Laboratories stock (RML). 1 Spirochetes were enumerated by dark-field microscopy [14]

Summary

Introduction

The reappearance of borreliae in a patient's blood during a second, third, or fourth febrile crisis of relapsing fever has suggested to students of this disease that these spirochetes undergo antigenic variation [1,2,3,4]. Meleney summarized the state of knowledge of this phenemenon in 1928 [4]: "At the time of the crisis which terminates the attack of fever, there is rapid agglutination and destruction of the spirochetes with the subsequent formation of immune bodies in the blood These substances are specific for the strain of spirochetes which was present during the preceding attack, but have no influence on the spirochetes of the succeeding relapse. There has been considerable interest among biologists in similar phenomena shown by the salivarian trypanosomes [8,9,10,11,12], relatively little is known of borrelial antigens, their locations in the cells, and the mechanism of antigenic variation Using both polyclonal antisera and monoclonal antibodies, we have identified in whole cell lysates of B. hermsii an abundant protein that is serotype specific

Methods

Results

Discussion

Conclusion