title: Functional properties of T cells in patients with chronic T gamma lymphocytosis and chronic T cell neoplasia.
abstract: The expanded T cell populations of 10 patients with either T gamma lymphocytosis (five patients) or proven chronic T cell malignancy (five patients) were analyzed with respect to functional activity in vitro, including proliferative responses to mitogens, cytotoxic activity (killer [K] and natural killer [NK] cell activity), and regulatory activity on pokeweed mitogen- (PWM) induced immunoglobulin (Ig) synthesis (help and suppression) in comparison with marker phenotypes. In each of the five patients with T gamma lymphocytosis, only one out of three functionally distinct cell types was found: T gamma-K cells, T gamma-S cells, or T gamma-NK/K cells, which mediated K-cell activity, suppressive activity, and both NK and K cell activity, respectively. An expanded T gamma-K cell population was demonstrated in three patients with neutropenia with or without recurrent infections. T gamma-S cells were found in a patient with severe hypogammaglobulinemia, and T gamma-NK/K cells in one patient with asymptomatic lymphocytosis. T gamma-K and T gamma-S cells had a similar surface-marker profile (E+ or E-, Fc gamma+, OKT1-3+4-8+I1-M1-), whereas that of T gamma-NK/K cells was different (E+, Fc gamma+, OKT1-3-4-8-I1+M1+). Longitudinal studies of three untreated patients with T gamma-K lymphocytosis showed that the abnormalities were persistent but not progressive. In contrast, five patients with chronic T cell malignancy (two with T-CLL, two with cutaneous T cell lymphoma [CTCL], and one with T-PLL) all had progressive disease. The neoplastic cells in these cases were E+, Fc gamma-OKT1+4+6- with variable expression of the OKT3 and OKT8 markers. The only functional activity observed in these cells was suppressive activity by OKT3-4+8- cells from a patient with CTCL.
mesh_terms: D000328:Adult; D000368:Aged; D002908:Chronic Disease; D003602:Cytotoxicity, Immunologic; D005260:Female; D006801:Humans; D007075:Immunoglobulin M / Q000096:biosynthesis; D007694:Killer Cells, Natural / Q000276:immunology; D007945:Leukemia, Lymphoid / Q000276:immunology; D008213:Lymphocyte Activation; D008218:Lymphocytosis / Q000276:immunology*; D008223:Lymphoma / Q000276:immunology; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology
chemical_list: D007075:Immunoglobulin M