Poliomyelitis Viruses in Tissue Culture. IV. Protein-Free Nutrient Media in Stationary and Roller Tube Cultures. ∗

Summary

Poliomyelitis virus may be propagated in test tube, plasma-clot cultures of monkey testicular tissue in the absence of protein in the fluid phase of the nutrient medium. The tubes may be held stationary with the fragments submerged under a thin layer of medium, or they may be turned in a roller drum. The medium used contained lactalbumin enzymatic hydrolysate, serum ultrafiltrate, and balanced salt solution. With such a medium, fibroblasts grow out within 4 days after the cultures are made, and are then suitable for use in virus titrations and neutralization tests in which the presence of virus is indicated by its cytopathogenic effect on the fibroblasts. Also such cultures continue to produce virus for a period of about four weeks, long after the degeneration of the fibroblasts.