Abstract

Tissue sections embedded in paraffin and fixed in formalin from 32 patients with Hodgkin's disease, representing the major histological subtypes, were studied using two granulocyte specific monoclonal antibodies (Leu-M1 and 3C4) and an HLA-D region specific monoclonal antibody (TAL-IB5). Reed-Sternberg cells were stained with one or other of the antigranulocyte antibodies in the nodular sclerosing and lymphocyte depleted subtypes. Reed-Sternberg cells in all but three cases of mixed cellularity Hodgkin's disease were positive with both Leu-M1 and 3C4. One case stained with only Leu-M1, and two cases were consistently negative with both antibodies. HLA-DR was widely expressed in the Reed-Sternberg cells of all three subtypes. In the four cases of lymphocyte predominant Hodgkin's disease the multinucleated Reed-Sternberg cells did not stain with either antigranulocyte antibody but were strongly positive with anti-HLA-DR. Twenty five cases of non-Hodgkin's lymphoma, in which there were multinucleated giant cells resembling Reed-Sternberg cells, were studied in a similar way. These cases included pleomorphic T cell and B cell lymphomas, histiocytic lymphomas, and malignant histiocytosis of the intestine. In none of these did the multinucleated cells stain with either antigranulocyte antibody, but in most cases the multinucleated cells stained with anti-HLA-DR. In two cases of the tumour stage of mycosis fungoides dot like intracytoplasmic staining was shown in the tumour cells with both antigranulocyte markers. The monoclonal antigranulocyte antibodies Leu-M1 and 3C4 are of considerable value in both the diagnosis and the differential diagnosis of Hodgkin's disease and are particularly valuable in that they can be applied to tissue fixed in formalin and embedded in paraffin. Antibody to HLA-DR, while useful, is of less value.