Properties of an EBV-B cell line derived interleukin 1 (IL 1) receptor

The properties of an human IL 1 receptor on a human EBV-B line were studied. Purified human IL 1-..beta.. produced by a myelomonocytic cell line (THP-1) was labeled with /sup 125/I by the Bolton-Hunter method without loss of biological activity. Among four EBV-B cell lines tested, a pre-B cell type (VDS-O) specifically bound the most /sup 125/I IL-..beta... Maximal binding was reached within 20 min at 4/sup 0/C. Scatchard analysis of the binding of /sup 125/I-IL 1-..beta.. to VDS-O cells yielded a Kd of 2.4-5.9 x 10/sup -00/ M with 110 to 220 binding (receptor) sites/cell. The binding of /sup 125/I-IL 1-..beta.. to VDS-O cells was inhibited by anti-human IL 1 antibody, natural and recombinant human IL 1-..cap alpha.. as well as IL 1-..beta.., but not by IFN-..cap alpha.., TNF, or LT, suggesting that IL 1-..cap alpha.. and IL 1-..beta.. specifically bind to the same receptor. The mw of the IL 1 receptor on human EBV-B cells was estimated to be 60 Kd both by a chemical crosslinking method and by HPLC gel filtration analysis of solubilized receptor extracted from membranes by a nonionic detergent (CHAPS). The pI of solubilized human IL 1 receptor was 7.3 by HPLC chromatofocusing. Datamore » showing that VDS-O cells proliferate in response to exogenously added IL 1, express IL 1 receptors and also produce IL 1 all support the hypothesis that IL 1 may function as an autocrine signal for B lymphocytes.« less