CD30 LIGAND EXPRESSION IN NONMALIGNANT AND HODGKINS DISEASE-INVOLVED LYMPHOID-TISSUES

The CD30 ligand (CD30L) is a type II transmembrane glycoprotein of the tumor necrosis factor ligand superfamily. Recent cloning of CD30L has enabled studies to explore its function and tissue distribution. For instance, recombinant CD30L has been shown to co-stimulate T cells and to net as mitogen for Hodgkin's disease (HD)-derived cell lines. The counter-receptor for cD30L, ie, CD30, is a type I cytokine receptor th at is highly expressed by activated T cells, Hodgkin and Reed-Sternber g (H-RS) cells, and anaplastic large cell lymphoma cells. In the prese nt study, recombinant membrane-bound and soluble human CD30L were inst rumental to raise a monoclonal antibody (M80) recognizing membrane-bou nd CD30L on transfected and native cells With this reagent, a panel of cultured lymphoma-derived cell lines as well as primary normal, react ive, and HD-involved lymphoid tissues were examined for expression of CD30L immuno-staining and flow cytometry. In reactive lymph nodes and tonsils, CD30L was expressed by a small subset of lymphoid cells, hist iocytes, and granulocytes. Higher levels of CD30L expression were note d in HD lesions among bystander cells, ie, T cells and granulocytes th at surrounded H-RS cells. Native CD30L displayed at the cell surface w as functionally active as shown by the ability of fixed granulocytes t o interact with CD30(+) cell lines. Moreover CD30L. was detectable, al though to a lower staining intensity, in primary H-RS cells of all HD tissues investigated regardless of the histological subtype and the ph enotype of H-RS cells (ie, CD30(+)/CD40(+) versus CD30(-)/CD40(+)). Co -expression of CD30 and CD30L that was seen on H-RS cells of all, exce pt the CD30(-) nodular lymphocyte predominant, subtypes of HD may poin t to the use of this pair of molecules in paracrine and/or autocrine m itogenic cell interactions. Monoclonal antibody M80 may thus represent a useful tool for studying CD30L expression on cultured cell lines an d primary cells from normal, reactive, and malignant tissues.