Effect of thymus extract and late thymectomy on interferon generation

: No production of interferon was observed in ten-day mice in response to the injection of the Newcastle disease virus. Single injection of the calf thymus extract fraction obtained by the method of Gujlling et al. to newborn mice induced the capacity of interferon genesis in the animals at the age of ten days. Adult rats produced interferon in response to Newcastle disease virus. The intensity of interferon synthesis was unaltered 2 to 3 months after thymectomy.