CLONING AND CHARACTERIZATION OF A SURFACE-ANTIGEN OF EIMERIA-TENELLA MEROZOITES AND EXPRESSION USING A RECOMBINANT VACCINIA VIRUS

A rabbit serum raised against Eimeria tenella merozoites was used to screen a lambdagt11 cDNA library made from merozoite mRNA of E. tenella. The insert of the phage clone lambdaMz 5-7 revealed an open reading frame consisting of 945 nucleotides, encoding a 33-kDa protein. This size is consistent with the size of a protein translated in vitro from merozoite mRNA and immunoprecipitated with monospecific anti-Mzp 5-7 antibodies, A smaller protein of 24 kDa, located on the surface of the parasite, also reacted with the monospecific antiserum and is the potential processed form of the Mzp 5-7. Furthermore, a recombinant vaccinia virus expressing the Mzp 5-7 antigen was constructed and used to immunize chickens.