Evaluation of the cell-mediated immune response to reduced doses of Mycobacterium avium ssp. paratuberculosis vaccine in cattle.
Vaccination against Johne's disease with an inactivated, oil-adjuvanted Mycobacterium avium ssp. paratuberculosis (MAP) bacterin can reduce clinical signs in infected herds; however, the development of indurated swelling at the injection site limits vaccine acceptability to producers. This study determined whether a reduced dose of vaccine antigen, with a full dose of adjuvant, would produce comparable T cell-mediated immune responses with smaller lesions. T cell responses induced by in vitro stimulation with MAP antigen from calves vaccinated with full, half, and quarter doses of antigen were evaluated 2, 4, and 9 months after vaccination by multi-parameter flow cytometry (FCM) and the whole blood interferon-gamma (WB IFN-gamma) assay. The WB IFN-gamma responses were significantly elevated in vaccinated animals, but did not differ significantly between doses. FCM demonstrated antigen-specific responses for both IFN-gamma and IL-4 in the CD4 T cell population from vaccinated animals, while CD8 T cells and gammadelta T cells mainly responded with increased IFN-gamma. Dose may have affected some T cell subset parameters at some time points, but intradermal skin test responses, WB IFN-gamma production, IFN-gamma responses by T cell subsets in FCM were not significantly different between full, half, or quarter doses of antigen. Injection site lesions were smaller in animals vaccinated with a lower dose of antigen, but reached statistical significance (P<0.05) in the half dose group only.
Platt
Ratree
R
Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA.
Thoen
Charles O
CO
Stalberger
Robert J
RJ
Chiang
Yu-Wei
YW
Roth
James A
JA
D000276:Adjuvants, Immunologic / Q000008:administration & dosage; D000818:Animals; D000942:Antigens, Bacterial / Q000008:administration & dosage; D001428:Bacterial Vaccines / Q000008:administration & dosage* / Q000009:adverse effects; D002417:Cattle; D002418:Cattle Diseases / Q000276:immunology* / Q000517:prevention & control*; D004306:Dose-Response Relationship, Immunologic; D007111:Immunity, Cellular; D007371:Interferon-gamma / Q000097:blood; D015847:Interleukin-4 / Q000097:blood; D016927:Mycobacterium avium subsp. paratuberculosis / Q000276:immunology*; D010283:Paratuberculosis / Q000276:immunology* / Q000517:prevention & control*; D016176:T-Lymphocyte Subsets / Q000276:immunology; D014611:Vaccination / Q000009:adverse effects / Q000379:methods / Q000662:veterinary*
D000276:Adjuvants, Immunologic; D000942:Antigens, Bacterial; D001428:Bacterial Vaccines; D015847:Interleukin-4; D007371:Interferon-gamma