The expression of gamma delta T cell receptor and the prevalence of primed, activated and IgA-bound T cells in Behçet's syndrome.
Mucosal ulceration of the oral, and to a lesser extent genital tissues is an essential feature of Behçet's syndrome and is associated with changes in the IgA class of immune responses. Indeed, a significant increase in the proportion of cytophilic IgA1 was found in circulating CD8 and CD4 cells (P less than 0.01), with a corresponding decrease in IgA-Fc receptors on these T cells. Furthermore, 30-40% of the cytophilic IgA1 on T cells may have been of the polymeric secretory type and the rest of the monomeric variety. IgA isotype of B cells was also significantly increased (P less than 0.001), without an overall change in circulating B cells. However, a surprising finding was the significant up-regulation of gamma delta T cell receptor in the CD8 (P less than 0.01) in the absence of a change in the proportion of alpha beta T cell receptor. The results suggest that some common microbial antigen might initiate at the mucosal surface an immune defence reaction characterized by T cells with gamma delta receptors and IgA-specific B cells. However, IgA1 bound to circulating T cells may down-regulate the central T cell function.
Fortune
F
F
Department of Immunology, United Medical School, Guy's Hospital, London, England.
Walker
J
J
Lehner
T
T
D000328:Adult; D001402:B-Lymphocytes / Q000378:metabolism; D001528:Behcet Syndrome / Q000276:immunology* / Q000378:metabolism; D005260:Female; D006801:Humans; D007070:Immunoglobulin A / Q000378:metabolism*; D007144:Immunoglobulin J-Chains / Q000378:metabolism; D016130:Immunophenotyping; D007958:Leukocyte Count; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D011948:Receptors, Antigen, T-Cell / Q000378:metabolism*; D011961:Receptors, Fc / Q000378:metabolism; D016176:T-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D015854:Up-Regulation
D007070:Immunoglobulin A; D007144:Immunoglobulin J-Chains; D011948:Receptors, Antigen, T-Cell; D011961:Receptors, Fc