IL6 and infection: Our observation of increased IL-6 after infection with mutant HSV-2 is also unlikely to have directly led to diminished mucosal viral replication of our mutant strains, as exogenous IL-6 does not alter viral replication in vitro, and in a murine ophthalmic model of disease the lack of IL-6 does not lead to increased HSV replication in vivo[52].