Interferon-alpha yields from Sendai virus-induced human leukocyte cultures are enhanced by lowering the incubation...

Increased yields of Sendai virus-induced human leukocyte interferon (IFN-alpha) were obtained by lowering the incubation temperature from the initial 37 degrees C within 1 to 6 h after the addition of virus. Maximal stimulation was found when this was done 2 to 4 h after induction and when the lowered temperature was between 29 and 32 degrees C. Compared to cultures kept at 37 degrees C throughout, the resulting IFN-alpha yields were enhanced by 2.5- to 3-fold. This was mainly due to prolonged synthesis of IFN-alpha, which could be observed up to 20 h after induction, whereas in cultures kept at 37 degrees C the production of IFN-alpha had practically ceased approx. 10 h after the addition of virus.