Abnormal histamine-induced suppressor-cell function in atopic subjects.
To detect a potential defect in immunoregulatory function in atopic subjects, we studied histamine-induced suppressor-T-cell activity and histamine Type 1 and Type 2 receptors on T cells. Peripheral-blood mononuclear cells from 16 atopic subjects generated less histamine-induced suppressor activity than did those from 20 nonatopic normal controls (P less than 0.005). The percentage of T lymphocytes bearing histamine Type 2 receptors was lower in the atopic group than in the control group (P less than 0.001), but the percentage of cells with Type 1 receptors was the same in both groups. In the atopic subjects, the functional suppressor-cell abnormality positively correlated with the decreased phenotypic expression of histamine Type 2 receptors. No abnormality in concanavalin A-induced suppressor activity was detected in these subjects. Nonatopic control subjects with systemic mastocytosis had normal functional and phenotypic data, suggesting that chronic activation of atopic T cells in vivo by circulating histamine does not explain the abnormal histamine-induced suppressor response.
D000293:Adolescent; D000328:Adult; D002478:Cells, Cultured; D003208:Concanavalin A / Q000494:pharmacology; D005260:Female; D006632:Histamine / Q000494:pharmacology*; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D011969:Receptors, Histamine H1 / Q000032:analysis; D011970:Receptors, Histamine H2 / Q000032:analysis; D013601:T-Lymphocytes / Q000032:analysis; D050378:T-Lymphocytes, Regulatory / Q000187:drug effects / Q000276:immunology*
D011969:Receptors, Histamine H1; D011970:Receptors, Histamine H2; D003208:Concanavalin A; D006632:Histamine