Human leukocyte interferon: Isolation and characterization of several molecular forms

Purification of human leukocyte interferon by high-performance liquid chromatography yielded eight major interferon species. These were characterized by their molecular weight, amino acid composition, and antiviral activity on human and bovine cells. The molecular weights of the purified species ranged from 16,000 to 21,000. The tryptic peptide profiles of all the pure species were compared. Both amino acid compositions and tryptic peptide profiles revealed a structural similarity among the various species.