Chronic lymphocytic leukemia progenitor cells carry the antigens T65, BA-1, and Ia.
CLL B cells may be induced to form B-cell colonies in vitro. Colonies formed are monoclonal and appear to reflect the circulating malignant B-cell clone in vitro. Using hybridoma-produced monoclonal antibodies (MAB) and an in vitro B-cell colony assay, we have provided a characterization of the antigenic phenotype of the clonogenic CLL B cell. B-cell colony growth in both patients and normals was not altered by prior incubation with either MAB or complement (C') alone. CLL B-cell colony formation was markedly reduced after treatment with T101 and C', while normal colonies were unaffected (8 +/- 2 versus 107 +/- 10). None of the residual CLL B-cell colonies after T-101 and C' treatment reacted with T-101. However, BA-1 and la reactivity were still seen in residual CLL B-cell colonies following T-101 treatment. In contrast, a similar percentage reduction of B-cell colony growth was seen for both normals and CLL patients following treatment with BA-1 (76% versus 81%) and Q5/13 (89% versus 92%). These studies suggest that the CLL progenitor cell is characterized by the phenotype la+, BA-1+, T-101+. Better definition of the CLL progenitor cell has potential implications with regards to clinical utilization of MAB in the treatment of CLL.
D000911:Antibodies, Monoclonal / Q000276:immunology; D000951:Antigens, Neoplasm / Q000235:genetics*; D000954:Antigens, Surface / Q000032:analysis; D001402:B-Lymphocytes / Q000276:immunology; D002999:Clone Cells / Q000473:pathology; D003114:Colony-Forming Units Assay; D006801:Humans; D007945:Leukemia, Lymphoid / Q000276:immunology* / Q000473:pathology; D010641:Phenotype
D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D000954:Antigens, Surface