In summary, these results support the idea that IL-1 production is not required either for control of VSV replication in vivo, or for the induction of protective immune responses to VSV antigens after intramuscular immunization. Because the relative magnitude of immune response to foreign antigens expressed by VSV is generally similar to the relative magnitude of the immune response to VSVs own antigens [56] , we predict that IL-1 would also not be required for the induction of immune responses to vaccine antigens expressed by VSV. Nonetheless, determining whether IL-1 is important for the response to foreign (vaccine) antigens expressed by an rVSV will be an important direction for further study.