Susceptibility of Mice to Infection with the Mahoney Strain of Type 1 Poliomyelitis Virus.

Abstract

Using criss-cross passages between mice and tissue cultures (monkey kidney) a line of the Mahoney strain type 1 poliomyelitis virus was adapted to the intracerebral route in mice. Various passages were titrated in tissue cultures and mice inoculated intraspinally, intracerebrally and intraven. and an increase in potency for tissue cultures and mice demonstrated. The last passage contained more than l07.5ID50/ml. for tissue cultures, 102.5ID50/ml. for the intracerebral route and approx. 10 ID50/ml. for the intraven. route in 4 wks. old CFW mice. The cytopatho-genic effect in tissue cultures and the infectiv.ity in mice was neutralized by an anti-type 1 (Brunhilde) immune serum.