The effect of beta interferon on dendritic cells and cytokine synthesis by CD4+ T cells.

Background: Dendritic cells (DC) are a key regulator of the immune response, and interferon-beta (IFN-beta) is considered an immunomodulatory molecule for DC.

Objective: The purpose of this study was to evaluate the ability of IFN-beta treated DC to induce cytokine secretion by CD4+ T cells.

Methods: Dendritic cells were generated from blood monocytes with granulocyte-monocyte colony-stimulating factor and interleukin-4 with or without IFN-beta. We analyzed the production of CD4+ T helper cytokines (IL-17, IFN-gamma and IL-10) in the supernatant of the dendritic cell-T cell co- cultures by ELISA. We also studied the effects of HLA-G and costimulatory molecules on immature and mature DC.

Results: IFN-gamma and IL-17 decreased significantly in the presence of HLA-G-bearing DC compared to control cultures (p<0.05).

Conclusions: Using the mixed leukocyte reaction, we found that DC treated with IFN-beta mediated the inhibition of T cell activation via cytokine production. We conclude that this is important for preventing overactivation of the immune system.