Analysis of the Cytotoxic T Lymphocyte Response of MHC-defined Swine to Foot-and-mouth Disease Virus (170.14)

Abstract Foot-and-mouth disease (FMD) is a disease of cloven-hoofed animals that remains a threat to the livestock industry. FMD virus (FMDV) causes an acute infection characterized by fever and the formation of vesicles on the feet and tongue. This picornavirus is classified into seven serotypes and the current killed-virus vaccines provide antibody-mediated protection that is serotype specific. A next-generation vaccine that relies on non-replicating recombinant human adenovirus 5 (Ad5) has been shown to induce neutralizing antibodies. To date, the role of cytotoxic T lymphocytes (CTLs) has been marginally explored. We have shown that swine vaccinated with an Ad5 vectored vaccine that targets the CTL response exhibited greater CTL killing of MHC-matched target cells compared to swine given the aforementioned Ad5 FMDV vaccine. In two trials with the T cell vaccine, the CTL response showed limited epitope specificity by class I MHC tetramer staining. Using these assays, we now show that FMDV infection also elicits a CTL response with broader epitope specificity than that induced by vaccination. These data provide a basis for evaluating whether CTLs can protect against disease following virus challenge.