title: Alteration in T lymphocyte subpopulations in inflammatory bowel disease.
abstract: Peripheral blood mononuclear cells from thirty-one patients with inflammatory bowel disease (ulcerative colitis and Crohn's disease) were analysed for the proportions and absolute numbers of total T cells, and for the T cell subpopulations carrying Fc receptors for either IgM (Tmu cells) or IgG (T gamma cells). Twenty-six control subjects were studied simultaneously. Total T cell numbers were normal in patients with inflammatory bowel disease but there was a marked reduction in the proportion and absolute numbers of Tmu cells in patients, whether their disease was active or in remission. T gamma cells were normal. Simultaneous assessment of lymphocyte response to mitogens in vitro was performed in a group of patients. Responses to phytohaemagglutinin, concanavalin A and pokeweed mitogen were decreased and a positive correlation was found between the number of circulating Tmu cells and the responses to mitogens in vitro. These studies demonstrate that despite the presence of normal numbers of total T cells in inflammatory bowel disease, there is a marked imbalance in T cell subpopulations that correlates with mitogen responsiveness. This imbalance provides a possible cellular basis for the defect in cell-mediated immunity seen in these patients.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003093:Colitis, Ulcerative / Q000276:immunology*; D003424:Crohn Disease / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology; D007075:Immunoglobulin M / Q000276:immunology; D007958:Leukocyte Count; D008213:Lymphocyte Activation; D008875:Middle Aged; D008934:Mitogens / Q000494:pharmacology; D011961:Receptors, Fc / Q000032:analysis; D013601:T-Lymphocytes / Q000145:classification* / Q000276:immunology
chemical_list: D007074:Immunoglobulin G; D007075:Immunoglobulin M; D008934:Mitogens; D011961:Receptors, Fc