The effect of interferon on chicken spleen lymphocytes

The inhibitory activity of chicken interferon has been investigated on phytohemagglutinin (PHA)-induced DNA synthesis of chicken spleen lymphocytes inoculated with type 12 adenovirus and was purified by selective adsorption on Na-Al-silicate. As a control, the culture fluid of chicken leukocytes purified in the same manner was used. In some instances the control preparation also showed a slight inhibitory effect. To prove that the immunosuppressive activity of our interferon preparation was indeed due to its interferon content both the interferon and the control preparation were purified further by chromatography on Sephadex G 100 superfine gel. Only the fractions with antiviral activity of interferon preparation inhibited the PHA-response of the lymphocytes. The fractions with the same molecular weight of control preparation were without effect.