Heterogeneity of antigenic proteins in Indian isolates of Theileria annulata

Antigenic heterogeneity was studied in SDS-PAGE based protein profile and Western blotting based immunodominant protein pattern of in vitro cultured Theileria annulata schizonts of the three isolates collected from Gujarat, Rajasthan and Haryana states of India. A total of 29 protein bands of apparent molecular weight ranging between 97 kDa to 14 kDa, having 17 major and 12 minor proteins, were observed for all the three T. annulata isolates. Out of these, two proteins of 72 kDa and 29 kDa were absent in the lysate of uninfected bovine mononuclear cells indicating that these are schizont specific. Immunoblotting of schizont lysate of the three isolates with antiserum against each other revealed several immunoreactive proteins of different predicted molecular weights. A 37 kDa protein could be immunoblotted from Anand isolate only with homologous antiserum indicating that the protein is specific to this isolate. Although none of three isolates of T. annulata collected from three different parts of India differed in their protein profile yet they exhibit different immunoreactive proteins in schizonts of the three isolates when blotted with heterologous antiserum.