title: Studies on the clonal origin of human B cell leukemia using monoclonal anti-idiotype antibodies.
abstract: The clonal origin of an IgA1 kappa B cell leukemia in a 71-year-old man (WF) was examined using a monoclonal anti-Id antibody and a panel of monoclonal anti-VH antibodies. Immunofluorescent studies revealed that all surface IgA1 kappa + leukemic cells in WF's blood and 10% of the IgM+ B cells in his bone marrow expressed the WF Id. Three percent of the IgA1 kappa + leukemic cells in blood also expressed gamma-chains in their cytoplasm. Approximately 0.1%, 1%, and 10% of bone marrow mononuclear cells, respectively, expressed mu-chains, gamma-chains, and alpha-chains in their cytoplasm, but no detectable light chains or surface immunoglobulins. These mu, gamma, and alpha-positive cells had the convoluted nucleus and narrow cytoplasm characteristic of normal mu+ pre-B cells. Sequential isotype switching among this unusual pre-B population was indicated by co-expression of mu-chains and alpha-chains by 11% and 63%, respectively, of the gamma pre-B cells. These pre-B cells and the surface alpha-chains and cytoplasmic gamma-chains of the leukemic B cells were reactive with one of four monoclonal anti-VH antibodies. The data suggest malignant transformation of the clone before isotype switching, and also imply light chain precommitment at the pre-B cell level of differentiation.
mesh_terms: D000368:Aged; D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology*; D001853:Bone Marrow / Q000276:immunology; D001854:Bone Marrow Cells; D002478:Cells, Cultured; D002999:Clone Cells / Q000276:immunology; D006801:Humans; D006825:Hybridomas / Q000276:immunology; D007070:Immunoglobulin A / Q000096:biosynthesis / Q000145:classification; D007130:Immunoglobulin Idiotypes / Q000276:immunology*; D007945:Leukemia, Lymphoid / Q000276:immunology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C
chemical_list: D000911:Antibodies, Monoclonal; D007070:Immunoglobulin A; D007130:Immunoglobulin Idiotypes