Heterogeneity of interleukin 1 production in cultured Reed-Sternberg cell lines HDLM-1, HDLM-1d, and KM-H2.

Interleukin 1 (IL-1) is known for its role in modulating the immune response and is required for initiation of lymphocyte proliferation by means of increased IL-2 production by lymphocytes. Previously, the expression of IL-1 in H-RS cells in tissue sections was shown by using immunoperoxidase staining. For further confirmation, the production of IL-1 in cultured cells of the H-RS cell lines HDLM-1, HDLM-1d, and KM-H2 was examined by using a murine D10.G4.1 T cell proliferation bioassay and Northern blot hybridization with specific IL-1 cDNA probes. It was confirmed that two types of H-RS cells, HDLM-1 and KM-H2, can secrete IL-1, especially after treatment with phorbol ester. The amounts of IL-1 in H-RS cell culture medium ranged from approximately 0.5 to 2.5 ng/ml. The major IL-1 secreted by HDLM-1 cells was IL-1 alpha, and by KM-H2 cells was IL-1 beta. HDLM-1d cells did not produce IL-1. This finding indicates the heterogeneity of IL-1 production in H-RS cells. Such heterogeneity may apply to H-RS cells in vivo, based on the variable IL-1 staining of these cells in lymphoid tissues.