Chick interferon: heterogeneity of electric charge.

Chick interferon from allantoic fluid, virus-induced and partly purified, consists of several active components of different charge. The components are separable by elution at different pH values from a carboxymethyl-Sephadex column; they also occupy different pH zones in electrofocusing gradients. Most of the interferon is, however, isoelectric near neutrality.