title: Spurious E rosette formation in B cell chronic lymphocytic leukemia due to monoclonal anti-sheep RBC antibody.
abstract: The apparent simultaneous presence of surface markers characteristic of both B and T cells is a phenomenon being described with increasing frequency in patients with chronic lymphocytic leukemia (CLL). We describe a patient with CLL whose B lymphocytes possessed surface immunoglobulin reactive with neuraminidase-treated sheep erythrocytes (SRBCs) and produced E rosette formation. Cytofluorography using monoclonal antibodies demonstrated the B cell nature of these cells and the absence of the SRBC receptor. Further documentation that the binding of SRBCs was mediated through immunologic reaction included E rosette formation inhibition by monospecific antisera and hemagglutination of SRBCs by a paraprotein isolated from the patient's serum. Fusion of the CLL cells with a human hypoxanthine-aminopterin-thymidine-sensitive plasma cell line resulted in the production of human hybridomas that secreted the SRBC-reactive IgM antibody. An analysis of clinical histories of CLL patients whose cells exhibited this phenomenon from both immunologic and clinical perspectives is presented.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000502:physiology*; D000954:Antigens, Surface / Q000032:analysis; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D001667:Binding, Competitive; D001789:Blood Group Antigens / Q000276:immunology*; D005189:False Positive Reactions; D006386:Hemagglutination Tests; D006801:Humans; D006825:Hybridomas / Q000276:immunology / Q000378:metabolism; D007075:Immunoglobulin M / Q000502:physiology; D007945:Leukemia, Lymphoid / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D011947:Receptors, Antigen, B-Cell / Q000032:analysis; D012397:Rosette Formation; D012756:Sheep
chemical_list: D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D001789:Blood Group Antigens; D007075:Immunoglobulin M; D011947:Receptors, Antigen, B-Cell