A Novel Thioredoxin-Like Protein ofInvolved in Parasite Pathogenicity.

Abstract

Babesiosis poses a serious threat to immunocompromised individuals and the major etiological species offor human babesiosis is. Merozoites are a critical stage in the life cycle of. Several merozoite proteins have been demonstrated to play important roles in this process; however, most of the merozoite proteins ofremain unknown. In the present study, we identified a novel merozoite protein ofwith similar structure to the thioredoxin (Trx)-like domain of the Trx family, which was named asTrx-like protein (TLP). Western blot assays demonstrated that this protein was expressed byduring the erythrocytic infection process, and its expression peaked on day 7 post-infection. Immunofluorescence assay further showed that this protein is mainly expressed inmerozoites.TLP hold both heparin- and erythrocyte-binding properties, which are critical functions of invasion-related proteins. Immunization with recombinantTLP imparted significant protection againstinfection in mice. Taken together, these results suggest that the novel merozoite protein,TLP, is an important pathogenic molecule ofand may be a possible target for the design of babesiosis control strategy.