title: Quantitation of human thymus-leukemia-associated antigen in established hematopoietic cell lines by radioimmunoassay.
abstract: A competitive radioimmunoassay for a saline-soluble human thymus-leukemia-associated antigen (HThy-L) was applied for quantitation of this antigen in leukemia and normal hematopoietic cell lines. Highly increased quantities of HThy-L were detected in all T-cell leukemia lines tested, regardless of the presence or absence of receptors for sheep erythrocytes. This elevated level of HThy-L in combination with high terminal deoxynucleotidyl transferase and adenosine deaminase activities and the presence of a T-lymphocyte-specific surface antigen appear to represent stable phenotypic characteristics of T-cell lines. Most normal B-cell lines had low quantities of HTy-L. The level of HThy-L was slightly elevated in a considerable number of lymphoma B-cell lines and in all non-T, non-B leukemia cell lines tested. No relationship existed between quantities of HThy-L and an expression of different surface immunoglobulin isotypes in B-cell lines. Low quantities of HThy-L were detected in leukemia myeloid and myeloma cell lines as well as in B-cell leukemia lines originating from patients with B-cells acute lymphoblastic leukemia. Apparently, the increased quantities of HThy-L in T-cell leukemia lines may be related to certain stages of T-cell differentiation at which leukemia cell transformation occurs.
mesh_terms: D000951:Antigens, Neoplasm / Q000032:analysis*; D001402:B-Lymphocytes / Q000276:immunology; D002051:Burkitt Lymphoma / Q000276:immunology; D002454:Cell Differentiation; D002460:Cell Line; D006412:Hematopoietic Stem Cells / Q000276:immunology*; D006801:Humans; D007938:Leukemia / Q000276:immunology*; D007945:Leukemia, Lymphoid / Q000276:immunology; D015470:Leukemia, Myeloid, Acute / Q000276:immunology; D009101:Multiple Myeloma / Q000276:immunology; D011863:Radioimmunoassay; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000951:Antigens, Neoplasm