Trypanosoma evansi: Immunochemical studies of variant surface glycoprotein

Abstract

Trypanosomal soluble proteins were resolved in low ionic strength phosphate buffer (pH 8.0) through anion exchanger diethylaminoethyl (DEAE) cellulose columns. The unbound protein revealed a polypeptide mass of 66-67 kDa on sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS- PAGE). This antigen showed a strong precipitin arc in immunoelectrophoresis with homologous hyperimmune serum. The same protein was used as immunogen @ 20, 60, 120 and 320µg/ mouse in 4 groups of mice. None of the dose schedule elicited sufficient immune response and did not protect the mice after homologous challenge. Besides, the maximum dose of 320 µg/mouse enhanced the mean survival of 13 days only.