title: Protective immunity against Eimeria acervulina following in ovo immunization with a recombinant subunit vaccine and cytokine genes.
abstract: A purified recombinant protein from Eimeria acervulina (3-1E) was used to vaccinate chickens in ovo against coccidiosis both alone and in combination with expression plasmids encoding the interleukin 1 (IL-1), IL-2, IL-6, IL-8, IL-15, IL-16, IL-17, IL-18, or gamma interferon (IFN-gamma) gene. When used alone, vaccination with 100 or 500 mug of 3-1E resulted in significantly decreased oocyst shedding compared with that in nonvaccinated chickens. Simultaneous vaccination of the 3-1E protein with the IL-1, -15, -16, or -17 gene induced higher serum antibody responses than 3-1E alone. To evaluate protective intestinal immunity, vaccinated birds were challenged with live E. acervulina oocysts 14 days posthatch, and fecal-oocyst shedding and body weight gain were determined as parameters of coccidiosis. Chickens vaccinated with 3-1E protein showed significantly lower oocyst shedding and normal body weight gain than nonvaccinated and infected controls. Simultaneous immunization with 3-1E and the IL-2, -15, -17, or -18 or IFN-gamma gene further reduced oocyst shedding compared with that achieved with 3-1E alone. These results provide the first evidence that in ovo vaccination with the recombinant 3-1E Eimeria protein induces protective intestinal immunity against coccidiosis, and this effect was enhanced by coadministration of genes encoding immunity-related cytokines.
authors.affiliation: Animal Parasitic Diseases Laboratory, Animal and Natural Resources Institute, United States Department of Agriculture, BARC-East, Building 1043, Beltsville, MD 20705, USA.
authors.forename: Xicheng
authors.initials: X
authors.lastname: Ding
authors.forename: Hyun S
authors.initials: HS
authors.lastname: Lillehoj
authors.forename: Marco A
authors.initials: MA
authors.lastname: Quiroz
authors.forename: Erich
authors.initials: E
authors.lastname: Bevensee
authors.forename: Erik P
authors.initials: EP
authors.lastname: Lillehoj
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D002645:Chickens / Q000469:parasitology*; D003048:Coccidiosis / Q000517:prevention & control / Q000662:veterinary*; D016207:Cytokines / Q000235:genetics*; D004531:Eggs; D004539:Eimeria / Q000276:immunology*; D005243:Feces / Q000469:parasitology; D015316:Genetic Therapy; D011201:Poultry Diseases / Q000517:prevention & control*; D016052:Protozoan Vaccines / Q000276:immunology*; D014611:Vaccination; D022223:Vaccines, Subunit / Q000276:immunology; D014614:Vaccines, Synthetic / Q000276:immunology*
chemical_list: D000913:Antibodies, Protozoan; D016207:Cytokines; D016052:Protozoan Vaccines; D022223:Vaccines, Subunit; D014614:Vaccines, Synthetic