Effect of temperature on the induction of interferons by endotoxin and virus.

Postic, Bosko (University of Pittsburgh, Pittsburgh, Pa.), Catherine DeAngelis, Mary K. Breinig, and Monto Ho. Effect of temperature on the induction of interferons by endotoxin and virus. J. Bacteriol. 91:1277-1281. 1966.-The effect of ambient and body temperature on interferon formation in rabbits injected intravenously with virus differed from that seen after injection of endotoxin. Newcastle disease virus-induced interferon (VII) was elevated by increasing ambient temperature to 35 C, whereas cooling of the rabbit at 4 C resulted in low VII levels. Neither of these conditions affected the titers of endotoxin-induced interferon (EII). However, a significant enhancement of EII levels was found in sera of shorn rabbits, in which the body temperature was lower than in unshorn animals by 1.0 to 1.5 F and the pyrogenic response to endotoxin was less by about 2 F. This enhancement of EII by relatively low body temperatures was also in striking contrast to the reported enhancing effect of high body temperature of the rabbit on the lethal action of endotoxin. It is suggested that the temperature optimum for formation of EII is lower than for formation of VII.