Studies on the innate resistance of mice to infection with mousepox. II. Route of inoculation and resistance; and some observations on the inheritance of resistance.

Abstract

SUMMARYThe response of mice to ectromelia virus depends on the route of injection and the differences between C57 Bl and a susceptible strain of mice have been studied using different routes of injection.The difference in susceptibility between C57 Bl and stock mice appears earliest following the intravenous injection of ectromelia virus, and following splenectomy this difference is abolished.The strain difference is most pronounced when the virus is injected into the footpad. It is reduced to a minimum after intracerebral injection, probably because not enough antibody reaches the brain tissue. All resistance is abolished after intraperitoneal injection and for this no explanation is advanced.Following the intranasal instillation of virus, C57 Bl mice are less resistant because they die of the pneumonia which follows a vigorous local response in the lungs. They succumb to doses of virus which are not lethal by the footpad route, and with larger doses they even die earlier than stock mice.The difference in susceptibility following different routes of inoculation can be explained in terms of the difference in effectiveness of the antibody response and it has been shown that resistance is inherited as a single, autosomal, dominant factor.