ARS | Publication request: COSTIMULATORY MOLECULES AUGMENT DNA VACCINE-INDUCED IMMUNITY TO EXPERIMENTAL BOVINE TUBERCULOSIS

Submitted to: Research Workers in Animal Diseases Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: November 9, 2003
Publication Date: November 9, 2003
Citation: Maue, A.C., Waters, W.R., Palmer, M.V., Whipple, D.L., Minion, F.C., Brown, W.C., Estes, D.M. 2003. Costimulatory molecules augment dna vaccine-induced immunity to experimental bovine tuberculosis. Proceedings of the 84th Annual Meeting of the Conference of Research Workers in Animal Diseases. p. 120.

Technical Abstract: DNA vaccination is known to elicit robust cellular and humoral responses to encoded antigen. The co-administration of costimulatory molecules CD80 (B7-1), CD86 (B7-2) and CD40L (CD154) has been shown to enhance immune responses in several murine models. The role of costimulatory molecules in large animal models remains incompletely characterized. We have shown that the co-administration of CD80 and CD86, in addition to an existing candidate subunit DNA vaccine (ESAT-6) to bovine tuberculosis, enhances immune responses before and after challenge with virulent Mycobacterium bovis. ESAT/80/86 vaccinated cattle had increases in IgG1 and IgG2a serum antibody responses to rESAT-6 when compared to vector-treated animals. ESAT-6 DNA vaccinates also showed increases in antigen-specific IFN-g production and proliferative responses when compared to control animals. In addition, vaccination reduced bacterial load in the lungs and mediastinal lymph nodes of infected animals. ESAT/80/86 vaccinates had decreased pathology in the lungs and lymph nodes, as visualized by X-ray densitometry, gross examination and microscopic analysis. These results demonstrate that the co-administration of costimulatory molecules with antigen enhances bovine immune responses to DNA vaccination.