A comparison of the protective effect against Mengo virus infection in mice of interferons induced by polyI: C and Mengo virus

PolyI: C (complexed polyinosinic and polycytidylic acids) has been demonstrated to protect mice against infection with lethal doses of a highly virulent mutant of Mengo virus. However, the serum interferon titers it induced were considerably lower and of much shorter duration than the interferon titers induced by infection with the Mengo virus mutant. Evidence has been obtained that the interferon induced by polyI: C is as effective against Mengo virus infection as polyI: C itself. It has also been shown that, unit for unit (measured by the plaque reduction of vesicular stomatitis virus), the polyI: C-induced interferon is much more effective against Mengo virus infection than the Mengo virus-induced interferon itself.