An elaborate collection of lymphocytes exists which protect mucosal regions against infectious pathogens. These lymphocytes have been found to be linked, by preferential recirculatory pathways, in what has been termed a "common mucosal immune system". Thus, immunization at one mucosal site been associated with the generation of responses at distal mucosal regions. We have used mucosal infection with reovirus to explore basic questions of gut mucosal immunology. In this application we will extend our studies of mucosal immunology to the oral cavity. In particular, we propose to use two viral models to analyze the B and T cell responses in the oral region after various routes of immunization. We will continue our analysis of mucosal immunity using reovirus as a model. In addition, we will initiate a new direction for our laboratory by using mucosal infection with herpesvirus as a model for studies of viral-specific immunity in the oral cavity.