Induction of protective immune response in mice by a DNA vaccine encoding Trypanosoma evansi beta tubulin gene.

Surra, caused by Trypanosoma evansi, is an economically important veterinary disease of the tropics. Lack of effective drugs or vaccines have made surra a severe economic burden particularly in Asia and sub-Saharan Africa. In this study, a naked DNA construct encoding full length T. evansi beta (β) tubulin gene was used to immunize mice, to elicit a T. evansi β tubulin protein specific humoral immune response, delineated by ELISA. The serum cytokine profile post immunization, as determined by flow cytometry bead based assay, showed a predominant T helper cell Type 1 (Th1) response with significant increase in levels of IFNγ and TNFα. Lethal challenge with T. evansi blood-form trypomastigotes post immunization generated a β tubulin specific recall response and a stronger Th1 type serum cytokine profile which correlated with an extended survival and better control of parasitemia in the immunized mice.