Resistance to intestinal coccidiosis following DNA immunization with the cloned 3-1E Eimeria gene plus IL-2, IL-15, and IFN-gamma.
A cloned Eimeria acervulina gene (3-1E) was used to vaccinate chickens in ovo against coccidiosis, both alone and in combination with genes encoding interleukin (IL)-1, IL-2, IL-6, IL-8, IL-15, IL-16, IL-17, IL-18, or interferon (IFN)-gamma. Vaccination efficacy was assessed by increased serum anti-3-1E antibody titers, reduced fecal oocyst shedding, and enhanced body weight gain following experimental infection with E. acervulina. When used alone, anti-3-1E antibody titers were transiently, but reproducibly, increased at 2 wk and 3 wk posthatching in a dose-dependent manner. Similarly, significantly reduced oocyst shedding and increased weight gain were observed at relatively high-dose 3-1E vaccinations (> or =25 microg/egg). Combined immunization with the 3-1E and IL-1, IL-2, IL-15, or IFN-gamma genes induced higher serum antibody responses compared with immunization with 3-1E alone. Following parasite infection, chickens hatched from embryos given the 3-1E gene plus the IL-2 or IL-15 genes displayed significantly reduced oocyst shedding compared with those given 3-1E alone, while 3-1E plus IL-15 or IFN-gamma significantly increased weight gain compared with administration of 3-1E alone. Taken together, these results indicate that in ovo immunization with a recombinant Eimeria gene in conjunction with cytokine adjuvants stimulates protective intestinal immunity against coccidiosis.
Lillehoj
Hyun S
HS
Animal Parasitic Diseases Laboratory, Animal and Natural Resources Institute, USDA-ARS, Beltsville, MD 20705, USA.
Ding
Xicheng
X
Quiroz
Marco A
MA
Bevensee
Erich
E
Lillehoj
Erik P
EP
D000818:Animals; D002645:Chickens; D003001:Cloning, Molecular; D003048:Coccidiosis / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary*; D018076:DNA, Complementary / Q000235:genetics; D004539:Eimeria / Q000235:genetics*; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D017125:Genes, Protozoan / Q000235:genetics; D007371:Interferon-gamma / Q000235:genetics / Q000276:immunology; D007378:Interleukins / Q000235:genetics / Q000276:immunology; D010957:Plasmids / Q000235:genetics; D011201:Poultry Diseases / Q000276:immunology* / Q000469:parasitology / Q000517:prevention & control*; D013047:Specific Pathogen-Free Organisms; D014611:Vaccination / Q000662:veterinary*; D019444:Vaccines, DNA / Q000276:immunology*
D018076:DNA, Complementary; D007378:Interleukins; D019444:Vaccines, DNA; D007371:Interferon-gamma