|Jang, S - Research Institute Of Health And Environment|
|Lillehoj, E - University Of Maryland|
|Dupis, L - Seppic, Inc|
|Ben, Arous - Seppic, Inc|
Submitted to: Asian-Australasian Journal of Animal Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/16/2017
Publication Date: 3/21/2017
Publication URL: http://handle.nal.usda.gov/10113/5832846
Citation: Lillehoj, H.S., Jang, S.I., Panebra, A., Lillehoj, E.P., Dupis, L., Ben, A.J. 2017. In ovo vaccination using eimeria profilin and clostridium perfringens NetB proteins in montanide IMS adjuvant increases protective immunity against experimentally-induced necrotic enteritis. Asian-Australasian Journal of Animal Sciences. 30(10):1478-1485. https://doi.org/10.5713/ajas.17.0053.
Interpretive Summary: Necrotic enteritis (NE) is one of the most important enteric infectious diseases affecting global poultry production with an estimated annual economic loss of more than $2 billion, largely attributable to increases costs associated with medical treatments and impaired growth performance. Due to increasing worldwide restrictions on the use of antibiotic growth promoters, there is an increasing need for alternative strategies to reduce the incidence and severity of NE in commercial flocks. Therefore it is important to develop a novel strategy to prevent NE. In this paper, ARS scientists collaborated with scientists in France to identify important pathogen antigens and developed novel vaccination strategy to induce host protective immunity against NE. In this study, authors identified antigens from Eimeria and C. perfringens, two pathogens which cause NE, and used these two antigens to immunize developing chicken embryos. Chickens which were immunized with this vaccine showed reduced clinical signs and reduced disease pathology by attenuating the expression of proinflammatory response. Therefore, this paper demonstrates a new promising approach that can use subunit protein vaccines derived from Eimeria and C. perfringens to stimulate host immunity against NE in the presence of microemulsion in a developing embryo. Because embryo vaccination, compared with other routes of immunization, offers the advantages of reducing physiologic stress associated with post-hatch immunization and reduced labor costs, this new method of vaccinating a large number of poultry will help the global industry.
Technical Abstract: The effects of embryo vaccination with Eimeria profilin plus Clostridium perfringens NetB toxin proteins in combination with the Montanide IMS-OVO adjuvant on the chicken immune response to necrotic enteritis were investigated using an E. maxima/C. perfringens co-infection model. Eighteen-day-old broiler embryos were injected with PBS, profilin alone, profilin plus NetB proteins, or profilin and NetB combined with IMS-OVO adjuvant. Post-hatch birds were co-infected with E. maxima and C. perfringens, and body weights, intestinal lesions, serum anti-NetB antibody titers, NetB-stimulated spleen cell proliferation, and proinflammatory cytokine and chemokine mRNA levels in intestinal intraepithelial lymphocytes were measured. In ovo vaccination with profilin and NetB proteins plus IMS-OVO increased body weight gains, anti-NetB serum antibody levels, and NetB-stimulated spleen cell proliferation compared with immunization with profilin and NetB in the absence of adjuvant. By contrast, vaccination with profilin, NetB, and IMS-OVO decreased gut lesion scores and diminished the levels of transcripts encoding for LPS-induced TNF-alpha factor, tumor necrosis factor superfamily 15, and interleukin-8 compared with profilin and NetB alone. These results suggest that the IMS-OVO adjuvant potentiates host immunity to avian necrotic enteritis when administered in conjunction with the profilin and NetB proteins, and may reduce disease pathology by attenuating the expression of proinflammatory cytokines and chemokines implicated in disease pathogenesis.