title: Differential effects of IL-10 on proliferation and cytokine production of human gamma/delta and alpha/beta T cells.
abstract: Gamma/delta TCR bearing T lymphocytes represent a T-cell subset whose functional relevance remains unclear. Nevertheless these T cells may play a role in the early immune response against bacteria. Until now the regulatory mechanisms on this response have not been investigated. The study described here evaluated the immunoregulatory effects of Interleukin-10 on gamma/delta and alpha/beta TCR-positive T-cell clones and freshly isolated peripheral-blood mononuclear cells (PBMC). IL-10 has been shown previously to inhibit lectin and antigen-induced proliferation and cytokine production by alpha/beta T cells. The results outlined below show that rhIL-10 strongly inhibits lectin-induced production of IFN-gamma, TNF-alpha, IL-2, and to a lesser degree proliferation and IL-4 production of both T-cell subsets. As IL-10 did not inhibit proliferation but at the same time strongly suppressed cytokine production in various experiments, the hypothesis that it could function as a growth factor for human T cells as has been described for murine thymocytes was tested. The data demonstrate that, although the gamma/delta T-cell clones tested do not produce IL-10 they can use it as a growth factor in combination with IL-2, IL-4 or alone. Furthermore, IL-10 has the same properties on human alpha/beta T-cell clones and PBMC. In summary, it is shown that IL-10 has pleiotropic effects on gamma/delta and alpha/beta TCR+ T cells by inhibiting lectin-induced cytokine production and by acting as a growth factor for these cells alone or in combination with IL-2 or IL-4.
authors.affiliation: First Department of Medicine, University of Mainz, Germany.
authors.forename: J F
authors.initials: JF
authors.lastname: Schlaak
authors.forename: E
authors.initials: E
authors.lastname: Hermann
authors.forename: H
authors.initials: H
authors.lastname: Gallati
authors.forename: K H
authors.initials: KH
authors.lastname: Meyer zum Büschenfelde
authors.forename: B
authors.initials: B
authors.lastname: Fleischer
mesh_terms: D017252:CD3 Complex / Q000276:immunology; D016207:Cytokines / Q000096:biosynthesis*; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis; D016753:Interleukin-10 / Q000494:pharmacology*; D007376:Interleukin-2 / Q000096:biosynthesis / Q000494:pharmacology; D015847:Interleukin-4 / Q000096:biosynthesis / Q000494:pharmacology; D037102:Lectins / Q000494:pharmacology; D008213:Lymphocyte Activation; D008264:Macrophages / Q000276:immunology; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000032:analysis*; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000032:analysis*; D011994:Recombinant Proteins / Q000494:pharmacology; D016176:T-Lymphocyte Subsets / Q000166:cytology / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
chemical_list: D017252:CD3 Complex; D016207:Cytokines; D007376:Interleukin-2; D037102:Lectins; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D015847:Interleukin-4; D007371:Interferon-gamma