title: Enhancement of IgE synthesis and histamine release by T cell factors derived from atopic patients with bronchial asthma.
abstract: Culture supernatants of unstimulated T cells (TCS) derived from normal donors or from atopic patients with bronchial asthma were tested for their ability to regulate the spontaneous IgE synthesis by B cells of normal and atopic subjects. The same TCS were also tested for their influence on the histamine release from leukocytes of house dust mites-sensitive patients. Addition of TCS to B cell cultures from allergic donors induced a dose-dependent increase of the spontaneous IgE production without affecting the synthesis of IgG, IgM, and IgA. The potentiating activity of TCS was observed only in B cell cultures spontaneously producing IgE; TCS were still active on irradiated B cells. The maximal IgE-enhancing activity was observed when TCS were added at the onset of B cell cultures. The supernatants of T cells lysed at day 0 did not contain IgE-potentiating factors. The antigen-induced but not the spontaneous histamine release from leukocytes of house dust mite-sensitive patients was enhanced by pretreatment with TCS from allergic donors. The enhancing activities of TCS on IgE synthesis and on histamine release could be removed by absorption with IgE-Sepharose and subsequently recovered by elution with glycine buffer. The results indicate that T cells of patients with asthma spontaneously release IgE-binding factors capable of increasing both the spontaneous IgE synthesis by B cells and the antigen-induced histamine release.
mesh_terms: D001249:Asthma / Q000097:blood* / Q000150:complications; D001402:B-Lymphocytes / Q000378:metabolism; D001688:Biological Products / Q000494:pharmacology*; D016207:Cytokines; D006636:Histamine Release; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000097:blood* / Q000150:complications; D007073:Immunoglobulin E / Q000096:biosynthesis*; D013601:T-Lymphocytes / Q000378:metabolism
chemical_list: D001688:Biological Products; D016207:Cytokines; D007073:Immunoglobulin E