Production of interferon from cultured cells has required the presence of serum in the cell culture medium although it may be omitted during the period of interferon induction. In the system reported here a fully defined medium, free of protein, is employed. This permits the culture of the cells and all phases of interferon induction and release to be studied under completely defined conditions. The final product can easily be separated from its inducers to yield a preparation of high specific activity.
The ls strain of mouse fibroblasts, adapted to grow in suspension, has been under regular culture in this laboratory (Griffiths & Pirt, 1967; Birch & Pirt, 1969, 1970, 1971; Blaker & Pirt, 1971) in the protein-free medium (Birch & Pirt, 1970). The only polymer used in the medium is the uncharged polysaccharide methylcellulose.
BIRCHJ. R., PIRTS. J.1970; Improvements in a chemically defined medium for the growth of mouse cells (strain LS) in suspension. Journal of Cell Science 7:661
BIRCHJ. R., PIRTS. J.1971; The quantitative glucose and mineral requirements of mouse LS (suspension) cells in a chemically defined medium. Journal of Cell Science 8:693
BLAKERG. J., PIRTS. J.1971; The uptake of vitamins by mouse fibroblast cells (strain LS) during growth on a chemically defined medium. Journal of Cell Science 8:701
BUCKK. W., CHAINE. B., HIMMELWEITF.1971; A comparison of interferon induction in mice by purified Penicillium chrysogenum virus and derived double-stranded RNA. Journal of General Virology 12:131
DIANZANIF., CANTAGALLIP., GAGNONIS., RITAG.1968; Effect of DEAE-dextran on production of interferon induced by synthetic double-stranded RNA in L cell cultures. Proceedings of the Society for Experimental Biology and Medicine 128:708
DIANZANIF., GAGNONIS., CANTAGALLIP.1970; Studies on the potentiating effect of DEAE-dextran on interferon production induced by double-stranded synthetic polynucleotides. Annals of the New York Academy of Sciences 173:727
FALCOFFE., FALCOFFR., FOURNIERF., CHANYC.1966; Production en masse, purification partielle et caracterisation d’un interferon destine des essais therapeutique humains. Annales de l’Institut Pasteur III:562
FIELDA. K., TYTTELA. A., LAMPSONG. P., HILLEMANM. R.1967; Inducers of interferon and host resistance: II. Multistranded synthetic polynucleotide complexes. Proceedings of the National Academy of Sciences of the United States of America 58:1004
GRIFFITHSJ. B., PIRTS. J.1967; The uptake of amino acids by mouse cells (strain LS) during growth in batch culture and chemostat culture: the influence of cell growth rate. Proceedings of the Royal Society B 168:421
LOCKARTR. Z.1966 Biological properties of interferons. Criteria for acceptance of a viral inhibitor as an interferon. The Interferons Ed. by FinterN. B. Amsterdam; North Holland Publishing Company:
TILLESJ. G.1970; Diethylaminoethyl-dextran enhancement of interferon induction by a complexed polyribonucleotide. Proceedings of the Society for Experimental Biology and Medicine 133:1334
YOUNGNERJ. S., SCOTTA. W., HALLUMJ. V., STINEBRINGW. R.1966; Interferon induction by inactivated Newcastle disease virus in cell cultures and mice. Journal of Bacteriology 92:862