Effects of cytosine-phosphate-guanosine oligodinucleotides (CpG-ODNs) on oral immunization with protein antigen or replicating parasite

摘要

The purpose of this research was to investigate selected methods of mucosalimmunization for commercial chickens. Induction of mucosal immunity in commercialchickens through the use of orally administered subunit vaccines or throughimmunomodulation of the host??s response to live vaccines may be a viable means tocontrol enteric infections in commercial poultry. In the present investigations weevaluated a means for delivering protein antigen in the drinking water and the use ofCpG-ODNs, a recently reported mucosal adjuvant, in order to both improve thisresponse and to modulate the host??s immune response when vaccinated with field strainsof Eimeria acervulina and Eimeria tenella.In order to evaluate the efficacy of immunizing commercial poultry with subunitvaccines through the drinking water we chose the model antigen Bovine Serum Albumin(BSA). Chicks were administered BSA via intraperitoneal (I.P.) injection, oral cropgavage, or orally through the addition of BSA to the drinking water. These experimentsdemonstrated the efficacy of drinking water administration to induce antibodyproduction in the serum, intestine, and bile. When BSA was co-administered with CpGODNswe observed a modest increase in this response dependent upon dose.To evaluate the immunomodulation of the host response to live parasite usingCpG-ODNs we used three administration models. The first was a single dose of CpGODNswith a trickle immunization regime of Eimeria acervulina. The second was coadministrationof CpG-ODNs with a clinical dose of Eimeria acervulina or tenella. Thethird was pre-administration of CpG-ODNs 24 hours prior to the clinical dose of eitherspecies. These studies demonstrate that the first and third models were effective inreducing lesions and improving performance.