Surface immunoglobulins of lymphocytes in chronic lymphocytic leukemia and disseminated lymphosarcoma

Immunofluorescent staining was used to study the incidence of heavy and light chain determinants on the surface of blood lymphocytes from nine normal individuals, fourteen patients with chronic lymphocytic leukemia (CLL), seven patients with lymphosarcoma cell leukemia (LSL), and one hairy cell leukemia. In CLL, 46% of the lymphocytes stained for the μ chain component of the IgM immunoglobulin; this finding suggests a clonal lymphocytic population. In contrast, the surface immunoglobulins in LSL showed a preponderance of both γ and μ chains. The concomitant distribution of both heavy chain molecules on the same lymphocyte was further shown by double fluorescent staining. These results support the hypothesis that CLL and LSL are distinct lymphoproliferative disorders and that they arise from two different types of lymphocytes.