Protective immunity induced with the antigens fractionated by affinity chromatography from the second generation schizonts of Leucocytozoon caulleryi

A crude extract of the 2nd generation schizonts (2GS) of Leucocytozoon caulleryi and chicken serum containing serum-soluble antigens were applied to an immunoaffinity column using immunoglobulin of chickens recovered from L. caulleryi infections. The fractionated antibody-bound proteins showed several bands between 70 kDa and 35 kDa by the electrophoretic analysis. By immunization of chickens, the fractionated proteins conferred the protection at varying degrees comparable to that conferred by the unfractionated original materials. These results indicated that antiserum against 2GS can recognize the proteins involved in protective immunity.