Lymphocyte surface characteristics in malignant lymphoma.

The surface of lymphocytes obtained from fresh biopsy specimens from 41 patients with malignant lymphoma and from 30 normal subjects or patients with non-neoplastic lymphadenopathy were investigated. Immunoglobulin on the cell surface was used to identify B cells, whereas T cells were recognized by their reactivity with an antithymocyte antiserum and their ability to form rosettes with sheep erythrocytes. Normal and inflammatory lymph nodes were composed predominantly of T lymphocytes, as were nodes from 14 patients with Hodgkin's disease. Two thymomas were T cell proliferations, whereas a node from a patient with ataxia-telangiectasia was devoid of T lymphocytes. The presence of immunoglobulin on the cell surface indicated that 19 of 21 lymphocytic lymphomas were B cell proliferations, whereas the cells from 3 histiocytic lymphomas (reticulum cell sarcomas) and 1 mixed histiocytic and lymphocytic lymphoma were devoid of surface immunoglobulin. In immunoglobulin-positive tumors, one predominant heavy chain and one predominant light chain could usually be identified, thus establishing the clonal character of the neoplastic proliferation. Ten of 11 diffuse poorly differentiated lymphocytic lymphomas were composed of cells with large amounts of surface immunoglobulin, whereas only 1 of 5 diffuse well differentiated lymphocytic tumors contained such abundant surface immunoglobulin. The surface immunoglobulin data indicate the existence of at least two subspecies of B cell neoplasms. A small lymphocyte with sparse surface immunoglobulin proliferates as diffuse well differentiated lymphocytic lymphoma and chronic lymphocytic leukemia, whereas a larger lymphocyte with abundant surface immunoglobulin proliferates as diffuse poorly differentiated lymphocytic lymphoma and lymphosarcoma cell leukemia.