title: Biology and biochemistry of T cell-derived lymphokines. I. The coordinate synthesis of interleukin 2 and colony-stimulating factors in a murine T cell lymphoma.
abstract: Two cloned murine T cell lymphomas of identical lineage exhibit coordinate control of the synthesis of two lymphokines. One line, LBRM-33 5A4, growing in culture can be activated by phytohemagglutinin (PHA) to secrete Interleukin 2 (IL 2), a T cell growth factor, and colony-stimulating factor (CSF), a granulocyte/macrophage growth factor. In the absence of PHA, 5A4 cells do not produce IL 2 or CSF. The second line, LBRM-33 1A5, is incapable of IL 2 and CSF production after treatment with PHA. Stimulation of 1A5 cells with Interleukin 1 (IL 1) converts these cells to a state in which subsequent treatment with PHA leads to the production of IL 2 and CSF. When the 5A4 cell line is recloned, variant subclones can be isolated that do not produce IL 2 or CSF upon stimulation with PHA. The frequency of occurrence of nonproducing variants from 5A4 cells is approximately 1 in 20. Such clones appear to retain a stable nonproducer phenotype. Treatment of a number of these variant subclones with IL 1 prior to exposure to PHA results in the secretion of both IL 2 and CSF from cells. Thus, cell lines derived from cloned LBRM-33 tumor cells either produce both IL 2 and CSF upon stimulation with PHA or they do not produce either lymphokine. These results indicate that the synthesis of IL 2 and CSF in T cells may share common regulatory mechanisms. Further, the LBRM cells appear to be capable of oscillation between two phenotypes representing different states of lymphokine-producing cells.
mesh_terms: D000818:Animals; D002469:Cell Separation; D002999:Clone Cells / Q000276:immunology; D003115:Colony-Stimulating Factors / Q000096:biosynthesis*; D007376:Interleukin-2 / Q000096:biosynthesis*; D008213:Lymphocyte Activation; D008223:Lymphoma / Q000276:immunology*; D051379:Mice; D009374:Neoplasms, Experimental / Q000276:immunology; D010641:Phenotype; D010835:Phytohemagglutinins / Q000494:pharmacology; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D003115:Colony-Stimulating Factors; D007376:Interleukin-2; D010835:Phytohemagglutinins