Inoculation of Mice with Poliomyelitis Virus

Abstract

Nungester 1 demonstrated that when poliomyelitis virus was combined with mucin and injected intraperitoneally into 76 mice, death occurred in 22, muscular weakness in 13 and flaccid paralysis in 2 animals. The brains and cords of 12 of the 22 mice that died and 7 controls were examined by Weil. 2 In 2, the picture seen closely resembled the histopathology found in M. rhesus monkeys that died of poliomyelitis. These results were sufficiently important to encourage further work along the same line.

Commercial gastric mucin powder was sterilized dry by autoclaving, a 5% emulsion prepared and used as a diluent to make up a 2% suspension of potent poliomyelitis virus. All injections were made the same day that the mixture was prepared and each mouse received 1 cc. intraperitoneally. The results are tabulated in Table I. In controls, the diluent was either normal saline, normal cord in mucin, or mucin in saline. In one group, the diluent for the mucin and virus was convalescent poliomyelitis serum.

All mice of group I that died following the inoculation of virus and much showed a small amount of clear, straw-colored fluid in the peritoneal cavity. The upper part of the small intestine was swollen and yellow reddish brown in color. There was slight or moderate hyperemia of the lungs. A few had enlargement of the spleen and hyperemia of the liver. Autopsy examination of the mice of groups II and III showed their organs to be normal, while those of group V showed some swelling and redness of the small intestine, but it was distinctly less marked than that seen in the animals of group I.