Previous Article | Next Article ![]()
Infect. Immun., Apr 1997, 1440-1444, Vol 65, No. 4
A Centurion-Lara, T Arroll, R Castillo, JM Shaffer, C Castro, WC Van Voorhis and SA Lukehart
The 15-kDa lipoprotein of Treponema pallidum is a major immunogen during
natural syphilis infection in humans and experimental infection in other
hosts. The humoral and cellular immune responses to this molecule appear
late in infection as resistance to reinfection is developing. One therefore
might hypothesize that this antigen is important for protective immunity.
This possibility is explored by using both genetic and antigenic
approaches. Limited or no cross- protection has been demonstrated between
the T. pallidum subspecies and strains or between Treponema species. We
therefore hypothesized that if the 15-kDa antigen was of major importance
in protective immunity, it might be a likely site of antigenic diversity.
To explore this possibility, the sequences of the open reading frames of
the 15-kDa gene have been determined for Treponema pallidum subsp. pallidum
(Nichols and Bal-3 strains), T. pallidum subsp. pertenue (Gauthier strain),
T. pallidum subsp. endemicum (Bosnia strain), Treponema paraluiscuniculi
(Cuniculi A, H, and K strains), and a little- characterized simian isolate
of Treponema sp. (Fribourg-Blanc strain). No significant differences in DNA
sequences of the genes for the coding region of the 15-kDa antigen were
found among the different species and subspecies studied. In addition, all
organisms showed expression of the 15-kDa antigen as determined by
monoclonal antibody staining. The role of the 15-kDa antigen in protection
against homologous infection with T. pallidum subsp. pallidum Nichols was
examined in rabbits immunized with a purified recombinant 15-kDa fusion
protein. No alteration in chancre development was observed in immunized,
compared to unimmunized, rabbits, and the antisera induced by the
immunization failed to enhance phagocytosis of T. pallidum subsp. pallidum
by macrophages in vitro. These results do not support a major role for this
antigen in protection against syphilis infection.
Copyright © 1997, American Society for Microbiology
Conservation of the 15-kilodalton lipoprotein among Treponema pallidum subspecies and strains and other pathogenic treponemes: genetic and antigenic analyses
Department of Medicine, University of Washington, Seattle 98195, USA.
This article has been cited by other articles:
| J. Bacteriol. | J. Virol. | Eukaryot. Cell |
|---|
| Microbiol. Mol. Biol. Rev. | Clin. Vaccine Immunol. | All ASM Journals |
|---|