Does physiological interferon play a role in Mengo virus infection of mice?

NZB, BALB/c and C3H mice, differing in their production of physiological interferon (IFN), were used as models to investigate its role in their resistance to Mengo virus infection. These mouse strains also differ in their susceptibility to the infection. NZB and BALB/c mice, producing higher titers of physiological IFN than C3H mice, proved to be less resistant to the infection than the latter mouse strain. This suggests that physiological IFN does not play protective role against Mengo virus infection in NZB and BALB/c mice. Instead, the higher level of in vitro spontaneously released physiological macrophage IFN correlated with the higher death rate in Mengo virus infected mice (NZB > BALB/c > C3H). Our results suggest a reverse correlation between the amount of detectable physiological IFN and resistance to the infection.