PHORBOL-MYRISTATE ACETATE-STIMULATED PRODUCTION OF INTERLEUKIN-2 BY T-CELL LYMPHOMA AND CONSTITUTIVE PRODUCTION BY DERIVED HYBRIDOMAS

  • 1 January 1984
    • journal article
    • research article
    • Vol. 31  (5) , 497-505
Abstract
To isolate a stable tumor cell line source of IL-2 (TCGF), 19 murine T-cell lines and their derivatives were screened for both constitutive and mitogen-stimulated IL-2 production. The cloned subline of a mouse thymic lymphoma EL-4 designated as EL-4TF could be stimulated with PMA [phorbol myristate acetate] to produce 80 U/ml of IL-2. A TK- EL-4TFR mutant line was selected from the EL-4TF cell population by treatment with 5-BrdUrd [5-bromodeoxyuridine]. The EL-4-TFR cells were stimulated with PMA and fused with the cells of thymic lymphoma BW5147. The resulting BH3 hybrid cell population was repeatedly cloned and tested for constitutive IL-2 production: 2 of the BH3 hybridoma clones produced IL-2 constitutively. The IL-2 of EL-4TF origin supported permanent in vitro growth of IL-2 dependent, tumor-specific T killer cell line CTLL when present in culture medium at a concentration of at least 0.1. U/ml. Since the EL-4TF-derived IL-2 preparations were contaminated with PMA, it was of interest whether PMA alone has a growth-promoting activity in CTLL cell cultures. Permanent cultivation of CTLL cells in an IL-2-free medium containing PMA was not possible. However, both mitogenic and co-mitogenic effects of PMA on CTLL cells were observed.