COPPER CHELATE AFFINITY CHROMATOGRAPHY OF HUMAN FIBROBLAST AND LEUKOCYTE INTERFERONS

Human fibroblast and human leucocyte interferons display a strong affinity for the copper chelate of bis-carboxymethyl amino agarose, binding tenaciously over a wide pH range (7.4 to 4.0). Their binding is apparently irreversible on a sorbent saturated with copper (24.8 μmol of Cu2+/ml of column bed). However, both interferons can be partially recoverd from sorbents of lower copper content, prepared by leaching the columns with sodium citrate at pH 9.0. The recovery of fibroblast interferon from a leached sorbent (5.8 μmol of Cu2+/ml of column bed) is about 30% and that of leucocyte interferon about 60%. Moreover, the strength of binding of leucocyte interferon can be modulated by leaching copper chelateagarose with citrate of varying concentration.