Lymphokine-mediated induction of cytolytic activity in a T cell hybridoma.
Functionally inducible CTL hybridomas were constructed by fusing alloantigen-specific T cells (C57BL/6 alpha-DBA/2) with cells from the rat thymoma line W/FU (C58NT)D. A cloned hybridoma line (KSH.4.13.6) that was specifically cytolytic in the presence of activated rat spleen cell supernatant fluid (rat Con A SN) lost activity when transferred to normal medium. However, a cytolytic activity could be reinduced by culturing KSH.4.13.6 cells in medium containing rat Con A SN or secondary mixed leukocyte culture SN. By using various sources of SN, it was found that cytolytic induction required two different factors. PMA-induced EL-4 SN and SN from antigen-activated cloned T cells, neither of which were capable of inducing cytolytic activity alone, were able to synergize in the cytolytic induction of KSH.4.13.6 IFN-gamma and IL 1 failed to induce cytolytic activity even in the presence of EL-4 SN. Furthermore, this hybridoma produced macrophage activating factor (MAF) upon culture in rat Con A SN, although MAF production could not be induced by either specific antigen or lectins. The kinetics of induction and loss of cytolytic activity mediated by rat Con A SN were similar to those of the induction of MAF production. However, EL-4 SN, which by itself was incapable of inducing cytolytic activity, was able to induce MAF production in the KSH.4.13.6 hybrid to an extent similar to that induced by rat Con A SN. These results suggest that the induction of cytolytic activity and of MAF production in this cloned hybridoma cell line are regulated by different mechanisms. Such a functionally inducible T cell hybrid may provide a tool for biochemical and molecular analysis of T cell function and regulation, and of the characterization of cytokines required for CTL differentiation.
D000818:Animals; D002460:Cell Line; D003470:Culture Media; D003602:Cytotoxicity, Immunologic; D006825:Hybridomas / Q000276:immunology*; D007700:Kinetics; D007941:Leukemia P388 / Q000276:immunology; D008222:Lymphokines / Q000276:immunology* / Q000302:isolation & purification; D016215:Macrophage-Activating Factors; D012515:Mast-Cell Sarcoma; D051379:Mice; D051381:Rats; D013601:T-Lymphocytes / Q000276:immunology*; D013945:Thymoma / Q000276:immunology; D013953:Thymus Neoplasms / Q000276:immunology
D003470:Culture Media; D008222:Lymphokines; D016215:Macrophage-Activating Factors