Toxicity of NDV for Mouse Lungs

Abstract

Summary The toxicity of NDV, as measured in mouse lungs, has been described. It has been shown that pulmonary consolidation and death follow the intranasal instillation of large doses of virus and that these effects are caused by the virus, rather than by nonviral components of the inoculum. The gross and microscopic appearance of the lung lesions has been described. The pulmonary toxicity of NDV suspensions is abolished by procedures which destroy the property of infectivity for eggs and is neutralized by specific immune serum. After intranasal instillation, NDV appears to be rapidly adsorbed on lung tissue, and the toxic reaction cannot be suppressed by immune serum given promptly by the same route. Attempts to protect mice by vaccination either by the intraperitoneal or intranasal route were unsuccessful, although vaccinated mice develop antibodies capable of neutralizing the toxicity of virus suspensions in vitro. Multiplication of NDV virus in mouse lungs cannot be demonstrated even though measurements of the concentration of virus in lungs are made at frequent intervals. An hypothesis which might explain the mechanism of cell injury in virus infections, as well as in toxic reactions, has been formulated, and some of its implications were discussed.