Identification and characterization of antigenic proteins in Trichomonas vaginalis

Abstract

Trichomoniasis is a sexually transmitted disease caused by Trichomonas vaginalis, and has serious consequences for women’s health. To study the virulence factors of this pathogen, T. vaginalis surface proteins were examined using polyclonal antibodies specific to the membrane fractions of T. vaginalis. T. vaginalis expression library was constructed by cloning the cDNA derived from mRNA of T. vaginalis into a phage λUni-ZAP XR vector, and then used for immunoscreening with the anti-membrane proteins of T. vaginalis antibodies. The immunoreactive proteins selected via immunoscreening included adhesion protein AP65-1, -actinin, kinesin-associated protein, teneurin, and two independent hypothetical proteins. Immunofluorescence assays showed that AP65-1, one of the identified immunogenic proteins, is prevalent in the whole body of T. vaginalis. Finally, enzyme-linked immunosorbent assay (ELISA) was performed using trichomoniasis patient’s sera showing high reactivity to both AP65-1 and kinesin-associated protein of T. vaginalis. These results revealed that AP65-1 and kinesin-associated protein are immunogenic proteins which provide important information for future investigation on T. vaginalis-host interaction.