Production of large quantities of interferon with calf testicular cells and leucocytes.

Interferon (IF) was induced in calf testicle monolayer cultures and leucocycte suspension cultures with Semliki forest virus and Newcastle disease virus to evaluate the potency of those cells for producing IF in large quantities for clinical experiments. Interferon activity was measured by an RNA-inhibition test using Semliki forest virus as challenge. To produce 10(6) units of IF, leucocytes from 67-5 litres of blood or 7-2 X 10(9) testicle cells were needed.