Abstract
Production of an interferon-like substance was demonstrated in primary chick embryo cells inoculated with human adenoviruses. In this rescept various examined types behaved similarly. Treatment of the virus with homologous immune serum, heat or trypsin resulted in the loss of its inducing capacity. The presence of mycoplasma had no influence on the induction of the interferonlike substance due to adenoviruses. The studied characteristics of the interferon-like substance due to adenoviruses resemble those of the interferons previously reported.