Production and Purification of Human Leukocyte Interferon

Abstract

Interferon production in human leukocyte suspensions induced by Newcastle disease virus is significantly affected by the pH of the culture. The optimal pH for interferon production is higher than the physiological pH level. Human leukocyte interferon has at least three types of surface charge as demonstrated by DEAE-cellulose column chromatography. The molecular wight of these three types of interferon, as measured by gel chromatography on several kinds of Sephadex is equally 25000. The main fraction of human leukocyte interferon was purified approximately 1400-fold by a sequence of procedures which involved ammonium sulfate salting out, CM- and DEAE-cellulose column chro-matography and gel filtration on Sephadex G-50. Human leukocyte interferon of a high specific ac-tivity of about 2130000 units/mg of protein was thus obtained.