title: E receptors on blasts from untreated acute lymphocytic leukemia (ALL):  comparison of temperature dependence of E rosettes formed by normal and leukemic lymphoid cells.
abstract: The presence of receptors for sheep erythrocytes (E) and sufrace Ig on the bone marrow blasts was investigated in 29 children with untreated acute lymphocytic leukemia (ALL). In 6 of them more than 50% of the bone marrow blasts formed E rosettes, while in none of the 29 were surface Ig detected. The six children with rosette-forming blasts had WBS greater than 5 times 10-4/mm-3 at admission and 4 of them presented with thymic enlargement. E-positive ALL blasts and normal human thymocytes formed rosettes after incubation for 1 hr at 4 degrees C or 37 degrees C. In contrast, normal human peripheral T lymphocytes from blood, spleen, and pleural fluid also formed rosettes at 4 degrees C but these rosettes dissociated at 37 degrees C. In two patients with E-positive ALL, the disappearance from blood of cells forming rosettes at 37 degrees C during the 1st week of treatments paralleled the reduction in circulating blasts. Conversely, after 6 days of therapy almost one-half of the remaining cells formed rosettes at 4 degrees C and had the morphologic features of normal lymphocytes. We conclude that, in contrast to peripheral T cells, normal thymic cells and E-positive blasts share the property of forming E rosettes after 1-hr incubation at 37 degrees C. In patients with E-positive ALL this property may be used to evaluate drug effects upon leukemic and normal T lymphocytes.
mesh_terms: D000818:Animals; D001666:Binding Sites, Antibody; D001853:Bone Marrow / Q000276:immunology; D001854:Bone Marrow Cells; D002469:Cell Separation; D002648:Child; D004912:Erythrocytes / Q000276:immunology; D005260:Female; D005333:Fetus; D005455:Fluorescent Antibody Technique; D006412:Hematopoietic Stem Cells / Q000276:immunology; D006801:Humans; D007104:Immune Adherence Reaction; D007945:Leukemia, Lymphoid / Q000276:immunology*; D010063:Ovum; D010996:Pleural Effusion / Q000473:pathology; D011696:Purpura, Thrombocytopenic / Q000276:immunology; D012756:Sheep / Q000276:immunology; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes / Q000276:immunology*; D013696:Temperature; D013950:Thymus Gland / Q000166:cytology