Two recombinant Mycobacterium bovis BCG (rBCG) strains carrying the Eimeria tenella rhomboid gene (Rho) delivered by extrachromosomal vector pMV261 and integrative vector pMV361 were evaluated for their ability to protect chickens against E. tenella challenge. Chickens were immunized intranasal with BCG, rBCG pMV261-Rho, or rBCG pMV361-Rho twice at a 2-week interval. All the recombinant BCG immunized chickens developed specific immune responses, and there was a significant increases of the percentages of CD4(+) and CD8(+) cells compared to the control (P<0.05). Challenge experiments demonstrated that the two rBCG strains could provide significant protection against E. tenella challenge (Wang et al., 2009).
Wang et al., 2009: Wang Q, Li J, Zhang X, Liu Q, Liu C, Ma G, Cao L, Gong P, Cai Y, Zhang G. Protective immunity of recombinant Mycobacterium bovis BCG expressing rhomboid gene against Eimeria tenella challenge. Veterinary parasitology. 2009; 160(3-4); 198-203. [PubMed: 19117681].