Cell-mediated immunity to vesicular stomatitis virus infections in mice.

The T cell-mediated immune responses of mice against vesicular stomatitis virus (VSV) were assessed by measuring direct primary foot pad swelling after local VSV infection and cytotoxic activity in spleens. The cytolytic activity was mediated by T cells since it was anti-theta + complement sensitive, was restricted by the K and D region but not the I region of H-2 and rapidly increased after 4 days but decreased 8 days after systemic or local infection. Cytolytic activity was virus-specific as reciprocally tested with VSV and vaccina virus immune T cells. Measurable activity on day 7 depended on infectious virus dose, virus virulence, and non-H-2 genetic background of the host. More than half of the cytolytic activity wasblocked specifically by either immune anti-H2 or rabbit anti-VSV antisera. Analysis of the kinetics of appearance of antigenic changes using metabolic inhibitors, revealed that the changes that rendered target cells susceptible to lysis after infection, occurred within the first hour after infection.