title: Stimulated human peripheral T cells produce high amounts of IL-35 protein in a proliferation-dependent manner.
abstract: The p35 subunit of IL-12 and the Epstein-Barr virus-induced gene 3 (EBI3) have been shown to form a heterodimeric cytokine, named interleukin-35 (IL-35). Recently, mRNA expression of both IL-12p35 and EBI3 was clearly shown in stimulated human T effector cells. Here, we investigated the production of IL-35 protein in human anti-CD3/CD28-stimulated pan T cells as well as T cell subpopulations using a specific human IL-35 ELISA system. We measured high concentrations of IL-35 (up to 3 ng/ml) in cell culture supernatants of stimulated pan T cells as well as CD4(+), CD8(+) and CD4(+)CD25(-) T cell subpopulations at 72 h after stimulation. Very low amounts of IL-35, in the range of 100pg/ml, were detectable in supernatants of resting T cells. These observations could be confirmed using a dot-blot assay for IL-12p35 and EBI3. High concentrations of IL-35 could be also measured in cell culture supernatants of both, resting and stimulated CD4(+)CD25(+) T cells. In order to learn more about the regulation of IL-35 production, we studied the effect of dexamethasone, cyclosporine A and rapamycin on IL-35 production of anti-CD3/CD28-stimulated human pan T cells as well as CD4(+) and CD8(+) T cell subpopulations. All three drugs significantly suppressed IL-35 production of these cells in a proliferation-dependent manner. In summary, we could show that stimulated human peripheral blood T cells of healthy donors produce high amounts of IL-35 protein. However, the biological function of this cytokine remains to be elucidated.
authors.affiliation: Institute of Molecular and Clinical Immunology, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.
authors.forename: Karina
authors.initials: K
authors.lastname: Guttek
authors.forename: Dirk
authors.initials: D
authors.lastname: Reinhold
mesh_terms: D018106:CD28 Antigens / Q000276:immunology; D017252:CD3 Complex / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D049109:Cell Proliferation; D016572:Cyclosporine / Q000494:pharmacology; D003907:Dexamethasone / Q000494:pharmacology; D006801:Humans; D053765:Interleukin-12 Subunit p35 / Q000032:analysis / Q000378:metabolism; D053645:Interleukin-2 Receptor alpha Subunit / Q000378:metabolism; D007378:Interleukins / Q000032:analysis / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D008213:Lymphocyte Activation / Q000187:drug effects / Q000276:immunology; D015778:Minor Histocompatibility Antigens; D020123:Sirolimus / Q000494:pharmacology
chemical_list: D018106:CD28 Antigens; D017252:CD3 Complex; C097732:EBI3 protein, human; D053765:Interleukin-12 Subunit p35; D053645:Interleukin-2 Receptor alpha Subunit; D007378:Interleukins; D015778:Minor Histocompatibility Antigens; C532417:interleukin-35, human; D003907:Dexamethasone; D016572:Cyclosporine; D020123:Sirolimus
keywords: Cyclosporine A; Dexamethasone; EBI3; ELISA; Epstein–Barr virus-induced gene 3; FoxP3; IL; IL-35; PBMC; Stimulated human T cells; TGF-ß; forkhead box P3; interleukin; peripheral blood mononuclear cells; transforming growth facor-beta