Large-scale production and concentration of human lymphoid interferon

A stable and predictable production system is described for pilot plant quantities (milligram) of human lymphoid interferon, using suspension culture of an African Burkitt's lymphoma derived cell line Namalva with induction by Newcastle disease virus, B-1 strain. Cell cultures were grown in impeller-driven 50-liter fermentors with dilution of the postinduction culture using serum-free medium. High levels of dissolved oxygen were necessary for optimum cell growth. A total of 4,207 liters of interferon culture was produced in a series of 116 fermentor runs. An average yield of 3.5 log(10) international units of interferon per ml was realized before processing. Trichloroacetic acid was used to precipitate the interferon. An average of 3.35 log(10) international units of interferon per ml was recovered in the final nonpurified product.