Hamster Kidney Cell Tissue Cultures for Propagation of Japanese B Encephalitis Virus. ∗

Summary

(1) Monolayer HKC tissue cultures can be prepared on a routine basis by methods essentially identical with those currently in use for preparation of monkey kidney tissue cultures. In screen tests with 13 arthropod-borne agents and 3 types of polio-virus. HKC proved markedly susceptible to the CPE of Japanese B encephalitis. West Nile, Uganda S. Ilheus. Bunyamwera, and Semliki Forest viruses, only moderately susceptible to effects of the St. Louis encephalitis agent and the New Guinea C, Hawaiian, and Trinidad strains of dengue virus. In contrast, the Ntaya, Zika and Bwamba agents and the 3 types of poliovirus failed to show CPE. (2) Evidence has been presented for serial propagation of JBE virus through 8 serial transfers in HKC tissue cultures. CPE was eventually complete. After 6 passages the virus yield was greater than the starting inoculum, although the dilution factors had carried beyond the extinction point of infectivity of the original inoculum. (3) Identity of the Japanese B encephalitis virus after 6 serial passages in tissue culture was established by neutralization tests performed both in tissue cultures and in mice and thus indicates that the “test tube” procedure may prove useful as a serological tool in the laboratory.