In ovo administration of CpG oligodeoxynucleotides and the recombinant microneme protein MIC2 protects against Eimeria infections.
We have previously demonstrated that short oligodeoxynucleotides containing unmethylated CpG motifs (CpG ODNs) exert a positive effect on weight loss and oocyst shedding associated with Eimeria infection when injected in vivo. The present work investigated the effects of in ovo vaccination with CpG ODNs and an Eimeria recombinant microneme protein (MIC2), alone or in combination, on susceptibility to coccidiosis. In ovo injection of CpG ODNs alone enhanced resistance to experimental Eimeria acervulina infection as best exemplified by reduced oocyst shedding. Two CpG ODNs reduced the oocyst load, but did not affect weight gain. When co-administered with the recombinant microneme protein, both ODNs reduced oocyst shedding; however, only ODN D19 plus MIC2 consistently improved weight gain. Vaccinating with ODN 2006 or MIC2 protein curtailed oocyst shedding but did not enhance weight gain in Eimeria tenella-infected birds. Co-administration of CpG ODN and MIC2 did not have an additive effect in reducing the oocyst output; however, it resulted in the highest and lowest Ab response before and after Eimeria tenella infection, respectively. Collectively, CpG ODNs administered in ovo demonstrated immunoenhancing and adjuvant effects following Eimeria infections.
Dalloul
Rami A
RA
Animal Parasitic Diseases Laboratory, Animal and Natural Resources Institute, BARC-East, Building 1040, ARS, USDA, Beltsville, MD 20705, USA.
Lillehoj
Hyun S
HS
Klinman
Dennis M
DM
Ding
Xicheng
X
Min
Wongi
W
Heckert
Robert A
RA
Lillehoj
Erik P
EP
D000818:Animals; D000913:Antibodies, Protozoan / Q000032:analysis / Q000096:biosynthesis; D002460:Cell Line; D002642:Chick Embryo; D003048:Coccidiosis / Q000469:parasitology / Q000517:prevention & control*; D018899:CpG Islands / Q000276:immunology*; D004539:Eimeria / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005243:Feces / Q000469:parasitology; D009569:Nitric Oxide / Q000378:metabolism; D009841:Oligonucleotides / Q000276:immunology*; D015800:Protozoan Proteins / Q000627:therapeutic use*; D016052:Protozoan Vaccines / Q000276:immunology*; D014614:Vaccines, Synthetic / Q000276:immunology; D015430:Weight Gain
D000913:Antibodies, Protozoan; D009841:Oligonucleotides; D015800:Protozoan Proteins; D016052:Protozoan Vaccines; D014614:Vaccines, Synthetic; D009569:Nitric Oxide