Neoplastic kappa and lambda cells in a B-PLL with chromosome translocations of both light chain gene regions.
We describe a chromosome translocation t(2;13) (p11-12;p11) involving the kappa (kappa) light chain gene region (2p11-12), and a subsequent translocation t(11;22) (q23;11) involving the lambda (lambda) light chain gene region (22q11) within the same clone, in a patient with B-cell prolymphocytic leukaemia (B-PLL), of whose peripheral mononuclear cells 82% expressed (kappa) chains and 8% expressed (lambda) chains. Electron microscope (EM) studies using the immunogold method showed that both kappa- and lambda-producing cells were prolymphocytes. Immunoglobulin (Ig) gene analysis by Southern blotting demonstrated rearrangement of both Ig heavy (H) chain genes and one kappa gene. Although a lambda gene rearrangement corresponding to the minor lambda-positive population was not detected, a small monoclonal (M) band of IgM-lambda was present in the serum. The chromosome translocations and the pattern of light chain expression, particularly the lambda-producing cells, are discussed in the light of the restricted light chain expression observed in Burkitt's lymphomas with variant translocations involving the light chain genes.
D001402:B-Lymphocytes; D005260:Female; D006801:Humans; D007147:Immunoglobulin Light Chains / Q000235:genetics*; D007145:Immunoglobulin kappa-Chains / Q000235:genetics*; D007146:Immunoglobulin lambda-Chains / Q000235:genetics*; D007945:Leukemia, Lymphoid / Q000235:genetics* / Q000276:immunology; D008875:Middle Aged; D010641:Phenotype; D014178:Translocation, Genetic
D007147:Immunoglobulin Light Chains; D007145:Immunoglobulin kappa-Chains; D007146:Immunoglobulin lambda-Chains