Isolation of two species of human lymphoblastoid (Namalva) cell-derived interferon that differ in rates of clearance, size, and cell specificity.

Chromatography of human lymphoblastoid (Namalva) interferon on blue dextran Sepharose has separated the interferon activity into two species which differ in affinity to the dye Cibacron Blue F3GA. The separated species differ also in rates of clearance from the circulation of mice, size, and specificity toward human and bovine cells. The species retained by the dye manifests a slower clearance rate, is about 20,000 mol. wt., and is equally active on both human fibroblasts FS-11A and bovine cell line MDBK. The unretained species disappears from the circulation at a faster rate, is 16,000 mol. wt., is active on bovine cells, but almost inactive on human cells. It is suggested that a comparative study of the two species may aid in the elucidation of the causes responsible for the rapid clearance or bioinactivation of interferon.