Optimal control of interferon-gamma and tumor necrosis factor-alpha by interleukin-10 produced in response to one HLA-DR mismatch during the primary mixed lymphocyte reaction.
Interleukin (IL)-10 is an immunosuppressive cytokine potentially involved in the control of the allogeneic response. Several studies failed to detect it in mixed lymphocyte reaction supernatants. However, experiments using IL-10-specific antibodies, revealing its inhibitory action on interferon (IFN)-gamma and tumor necrosis factor (TNF)-alpha, provided indirect evidence that endogenous IL-10 was produced. The aim of the present work is to elucidate the role of IL-10 during mixed lymphocyte reaction and to investigate the influence of HLA-DR antigens on its production and on the regulatory loop involving TNF-alpha and IFN-gamma. Using a highly sensitive ELISA, a significant (P < 0.0001) but low IL-10 release could be detected (33.7 +/- 3.6 pg/ml) in response to HLA-DR disparities. However, IL-10 release was not graded as 1 DR mismatch (MM)-induced maximal secretion (32.3 +/- 5.1 pg/ml). This contrasted with TNF-alpha and IFN-gamma productions, which significantly increased in 2 DR MM pairs. Addition to IL-10-specific antibodies resulted in higher enhancement of INF-gamma (235 +/- 38% vs. 122 +/- 39%, P = 0.02) and, to a lesser extent, TNF-alpha (147 +/- 56% vs. 112 +/- 20%, NS) in 1 compared with 2 DR MM pairs. We conclude that the 1 DR MM setting is associated with optimal IL-10 secretion and more efficient inhibition of IFN-gamma and TNF-alpha compared with the 2 DR MM configuration. Although promoting enhanced IFN-gamma and TNF-alpha release, introduction of an additional DR MM does not result in increased IL-10 production. These data indicating that the IL-10 regulatory feedback loop is more effective in 1 DR rather than complete DR incompatibility could have an impact on matching policies for planned transfusion.
Toungouz
M
M
Department of Immunology and Transfusion, Erasme Hospital, Brussels Free University, Belgium.
Denys
C
C
de Groote
D
D
Andrien
M
M
Dupont
E
E
D019138:Antibodies, Blocking / Q000494:pharmacology; D001803:Blood Transfusion / Q000379:methods; D004797:Enzyme-Linked Immunosorbent Assay; D005246:Feedback; D006084:Graft Rejection / Q000517:prevention & control; D006684:HLA-DR Antigens; D006650:Histocompatibility Testing; D006801:Humans; D007165:Immunosuppression Therapy / Q000379:methods; D066298:In Vitro Techniques; D007371:Interferon-gamma / Q000096:biosynthesis*; D016753:Interleukin-10 / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D008070:Lipopolysaccharides / Q000494:pharmacology; D007959:Lymphocyte Culture Test, Mixed; D009500:Neutralization Tests; D014181:Transplantation Immunology; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis*
D019138:Antibodies, Blocking; D006684:HLA-DR Antigens; D008070:Lipopolysaccharides; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D007371:Interferon-gamma