The Role of Interferon in the Protection of ICR Swiss Male Mice by the Nondiabetogenic Variant of Encephalomyocarditis Virus Against Virus-Induced Diabetes Mellitus

The production of murine diabetes mellitus by the diabetogenic variant of encephalomyocarditis virus (EMCV-D) is prevented in mice preinfected for 24 h with nondiabetogenic virus (EMCV-B). It has been suggested that the protection of the animals is due to the induction of interferon (IFN) by EMCV-B. The present study was done to investigate further the role of IFN in the protection of male ICR Swiss mice against the diabetogenic effects of EMCV-D virus. The results show that this mouse strain is protected only by viable EMCV-B given by either the i.v. or i.p. route of inoculation and that the protection is not abrogated by anti-IFN γ-globulin. Further, the animals were not protected by either IFN-α, IFN- β, or IFN- α/β at concentrations shown previously to protect mice against the lethal effects of other variants of EMCV. The data provide further evidence that, in the ICR Swiss mouse, IFN does not play a major role in protecting pancreatic β-cells against infection by EMCV-D.