The physiological interferon response: IV. Production of interferon by the perfused human placenta at term.

Human placentas at term, free of bacterial and viral diseases, have been perfused and maintained sterile for up to 13 hr. Several parameters indicate that the organs remained viable and released interferon into the perfusate in a progressive fashion. The amount of interferon was small and the individual variations indicate that there are "poor" and "good" placenta producers. Both interferons -alpha and -beta were produced with a prevalence of the latter type. The partial acid lability and the type heterogeneity suggest that under physiological conditions the placentas produce unusual interferons, the function of which remains speculative.