Purification of avian T cell growth factor and immune interferon using gel filtration high resolution chromatography

A protocol was outlined to separate and purify chicken T cell growth factor or IL-2 and gamma interferon from conditioned medium of Con A activated spleen cells. IL-2 was associated primarily with a protein of 30 kDa in SDS-PAGE and in high resolution gel filtration chromatography. Chicken IL-2 was of low hydrophobicity. A second species of molecular weight 14 kDa was also identified by high resolution gel filtration chromatography. Purified IL-2 gave only 50% of the maximum growth response obtained with IL-2 in crude conditioned medium. Gamma interferon activity was associated primarily with protein of 17 kDa and a second peak of activity was detected with protein of 36 kDa. I-IFN was not cross reactive with human cells and was pH sensitive.