Kinetics of large-scale production of bovine leukocyte interferon, using three viral inducers

Kinetics of large-scale production of naturally derived bovine leukocyte interferon (IFN) was investigated using Sendai virus, Newcastle disease virus, and infectious bovine rhinotracheitis virus inducers. Cultures were tested for IFN production every 6 hours for 66 hours. The effect of varying the priming dose of Sendai virus from 0 to 50% of total virus dose and the effect of varying the priming time from 0 to 4 hours before induction also were investigated. Other factors explored were effects of varying the fetal bovine serum concentration (from 0 to 8%) and individual cow donors on bovine IFN titers. Highest bovine leukocyte IFN titers (15,314 U/ml) were obtained using Sendai virus (priming dose, 60 hemagglutinating units/ml; inducing dose, 240 hemagglutinating units/ml) and incubating for 12 hours. Up to 24 L (over 360 million U) of naturally derived leukocyte IFN were produced at one time.