T cell mediated immunoregulation plays an important role in protective immunity. The central molecular interaction, which dictates the selection of the specificity of T cells, depends on the interaction between MHC molecules and peptides derived from degraded antigenic structures. Here, we studied this interaction between bovine MHC class II molecules and peptides derived from foot and mouth disease virus (FMDV). Progress during the last decade in our understanding of the mechanisms underlying antigen recognition by T lymphocytes, opens the possibility to apply this knowledge in new approaches for the development of vaccines.

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