Characterization of a high affinity interleukin-1 (IL-1) specific binding site in a human synovial sarcoma (Hs431) cell line.
A subpopulation of cells was derived from the Hs431 connective tissue sarcoma cell line which possessed high affinity (estimated Kd = 0.38-0.55 nM) binding sites for human recombinant [125I]-IL-1 alpha. Binding at 4 degrees C was slow approaching equilibrium by 4 hrs. Dissociation of [125I]-IL-1 alpha was also slow and unaffected by high concentrations of cold ligand. The binding site also underwent ligand-induced internalization at 37 degrees C. An Mr = 83,000 protein was identified in affinity crosslinking studies. Despite these similarities to previously reported IL-1 receptors, Hs431 cells did not exhibit biological responses to IL-1 which have been observed in other cell lines. IL-1 did not induce PGE2 or collagenase synthesis. IL-1 also failed to induce ornithine decarboxylase activity (ODC) or stimulate [3H]-thymidine incorporation. In contrast, the Hs431 cells did contain a functional epidermal growth factor (EGF) receptor as determined from binding studies, protein kinase activity, induction of ODC, and stimulation of [3H]-thymidine incorporation. Thus, the refractoriness of Hs431 cells to IL-1 was fairly specific and did not result from a generalized defect associated with cell transformation.
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Department of Biological Research, Janssen Research Foundation, Spring House, PA.
Garrabrant
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D001665:Binding Sites; D066246:ErbB Receptors / Q000378:metabolism; D006801:Humans; D007375:Interleukin-1 / Q000378:metabolism*; D007457:Iodine Radioisotopes; D007700:Kinetics; D011971:Receptors, Immunologic / Q000378:metabolism; D017472:Receptors, Interleukin-1; D013584:Sarcoma, Synovial / Q000378:metabolism* / Q000648:ultrastructure; D014407:Tumor Cells, Cultured
D007375:Interleukin-1; D007457:Iodine Radioisotopes; D011971:Receptors, Immunologic; D017472:Receptors, Interleukin-1; D066246:ErbB Receptors