title: Lack of proliferative response by gluten-specific T cells in the blood and gut of patients with dermatitis herpetiformis.
abstract: The majority of patients with Dermatitis Herpetiformis (DH) have a gluten-sensitive enteropathy which may be triggered by a T cell-mediated immune response to gluten. Using a proliferative assay, the responses to gluten fraction III, recall antigens and mitogens of peripheral blood mononuclear cells (PBMC) and gut T cell lines (TCL) isolated from patients with Dermatitis Herpetiformis (DH) and normal controls were studied. In most cases, neither PBMC nor gut T cell lines (which were predominantly CD3+, CD4+, TCR alpha beta +) from either controls or patients proliferated in response to gluten fraction III alone. However, the addition of 10 U/ml IL-2 to PBMC cultures containing gluten fraction III resulted in a marked increase in proliferation in 9/19 DH patients and 7/11 controls compared to IL-2 alone. Furthermore, gluten-induced upregulation of IL-2 receptor (CD25) expression was demonstrated on PBMC from 4/4 patients with DH and 2/3 controls after 7 days' culture with antigen. A similar effect by exogenous IL-2, or the same concentration of IL-4, was observed in 8/11 (P = 0.02) and 5/6 respectively DH, and 3/4 normal gut T cell lines. No difference was observed in the response of DH and control PBMC to Tetanus toxin, Candida albicans and PPD; both normal and DH gut T cell lines were unresponsive to these antigens. However, the addition of IL-2 increased the response to Candida albicans by DH gut T cell lines. Moreover, the response of DH gut T cell lines to PHA (P < 0.001), Concanavalin A and anti-CD3 were markedly reduced compared to PBMC from the same patients. These findings suggest that gluten-specific T cells present in the blood and gut of normal and DH individuals are activated by but do not proliferate in response to specific antigen.
mesh_terms: D002176:Candida albicans / Q000276:immunology; D002460:Cell Line; D003874:Dermatitis Herpetiformis / Q000097:blood / Q000276:immunology*; D019084:Fluorescent Antibody Technique, Indirect; D005983:Glutens / Q000276:immunology* / Q000494:pharmacology; D006801:Humans; D007156:Immunologic Memory; D007376:Interleukin-2 / Q000494:pharmacology; D015847:Interleukin-4 / Q000494:pharmacology; D007421:Intestine, Small / Q000276:immunology; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects; D008934:Mitogens / Q000494:pharmacology; D015375:Receptors, Interleukin-2 / Q000378:metabolism; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology*; D013745:Tetanus Toxoid / Q000494:pharmacology; D014373:Tuberculin / Q000494:pharmacology
chemical_list: D007376:Interleukin-2; D008934:Mitogens; D015375:Receptors, Interleukin-2; D013745:Tetanus Toxoid; D014373:Tuberculin; D015847:Interleukin-4; D005983:Glutens