title: Disorders of regulatory T cells in patients with selective IgA deficiency and its relationship to associated autoimmune phenomena.
abstract: In vitro lymphocyte function of 13 patients with selective IgA deficiency was studied. IgG, IgA and IgM secretion by pokeweed mitogen-stimulated peripheral blood lymphocytes from normal donors and IgA deficient patients was measured by an enzyme-linked immunosorbent assay. Addition of concanavalin A or hydrocortisone and co-cultures of B and T cell enriched populations from patients and normal donors, allowed us to investigate B cell Ig production and T cell regulatory abnormalities. IgA production by these patients' B cells was either absent or very low, as compared to their total Ig production, even in the presence of optimal T cell help. Several T cell immunoregulatory abnormalities were seen in different patients. A moderate increase in suppressor activity selective for IgA production was observed in some, but does not appear to play a major role in the pathogenesis of the IgA deficiency. In others, with associated autoimmune phenomena, a decrease in suppressor T cell function was found.
mesh_terms: D000293:Adolescent; D000328:Adult; D001327:Autoimmune Diseases / Q000276:immunology*; D001402:B-Lymphocytes / Q000276:immunology; D002478:Cells, Cultured; D002648:Child; D002675:Child, Preschool; D004406:Dysgammaglobulinemia / Q000276:immunology*; D005260:Female; D006801:Humans; D017098:IgA Deficiency; D007136:Immunoglobulins / Q000096:biosynthesis; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D014066:Palatine Tonsil / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology
chemical_list: D007136:Immunoglobulins