Protection of Mice from Neurotoxic Action of Influenza Virus by "Heat Inactivated" Receptor Destroying Enzyme.

Abstract
Summary and Conclusion 1. Exposure of a solution of partially purified receptor destroying enzyme (RDE) to a temperature of 120°C for 30 minutes completely inactivated its erythrocyte receptor destroying activity but failed to inactivate its capacity to protect mice from the neurotoxic effect of influenza A virus. 2. It is concluded that heat denatured RDE is either still capable of protecting mice or that partially purified RDE contains a heat stable impurity that is capable of protecting mice but that does not affect hemagglutination.