title: B cell hyperactivity and abnormalities in T cell markers and immunoregulatory function in a patient with nucleoside phosphorylase deficiency.
abstract: We describe a 2 year old girl with nucleoside phosphorylase (PNP) deficiency, who had low blood T cell numbers and T lymphocyte blastogenic response to mitogens, hypergammaglobulinaemia, high titres of antibodies to many common antigens, various autoantibodies, a monoclonal IgM-kappa protein, an increased frequency of mature Ig containing blood B cells and a high production of Ig in vitro in unstimulated cultures. E rosetting cells showed faint or no immunofluorescence staining with monoclonal antibodies directed against T cell membrane antigens. In vitro Ig production in response to pokeweed mitogen was defective, and no T cell helper or suppressor activity was observed. It is suggested that the immunoregulatory deficiency might have caused the B cell hyperactivity.
mesh_terms: D000906:Antibodies / Q000032:analysis; D001323:Autoantibodies / Q000032:analysis; D001402:B-Lymphocytes / Q000276:immunology*; D002675:Child, Preschool; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D006942:Hypergammaglobulinemia / Q000276:immunology; D007136:Immunoglobulins / Q000096:biosynthesis; D008213:Lymphocyte Activation; D010430:Pentosyltransferases / Q000172:deficiency*; D011683:Purine-Nucleoside Phosphorylase / Q000172:deficiency*; D012397:Rosette Formation; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000906:Antibodies; D001323:Autoantibodies; D007136:Immunoglobulins; D010430:Pentosyltransferases; D011683:Purine-Nucleoside Phosphorylase