High Yield Culture of Human Fibroblasts on Microcarriers: A First Step in Production of Fibroblast-Derived Interferon (Human Beta Interferon)

Abstract

Production of large quantities of diploid human fibroblasts in small culture volumes can be achieved using microcarrier culture techniques. Modification of the microcarrier culture procedure to include a virtually static attachment period and a reduced culture volume during the first 6 h of culture doubled the attachment efficiency of the cells, improved the culture growth rate and increased final cell yields. Using the modified culture procedure, yields > 2 .times. 106 cells/ml could be regularly obtained when 7-8 viable cells/microcarrier were used to inoculate a culture containing 3 mg of Cytodex 1 microcarriers/ml. A protocol for the mass production of human .beta. interferon from microcarrier cultures is described. After priming the culture with .beta. interferon the superinduction step involves use of a poly (I) .cntdot. poly(C)/DEAE-dextran complex. Modifications to the microcarrier culture procedure and to the interferon production sequence enable the production of 3 .times. 108 IU of interferon from a 5 l microcarrier culture of human fibroblasts. This quantity of interferon corresponds to a yield of approximately 30 IU/103 cells or 2 .times. 104 IU/mg of microcarrier.