Interferon Regulatory Factor (IRF)3 is a crucial transcription factor during innate immune responses. Here we show IRF3 also has a role in adaptive T cell immune responses. Expression of IFN-γ, IL-17, and Granzyme B (GrB) during in vitro T cell responses was impaired when either dendritic cells (DCs) or T cells were derived from IRF3KO mice. Unexpectedly, IRF3-dependent NK-activating molecule (INAM), which is an NK cell activating factor of the DC innate immune response, was induced during the T cell response. Additionally, supernatants from responding T cells induced ISG54 in the RAW264.7 macrophage cell line in an IRF3 dependent manner. Moreover, addition of anti-IFN-γ prevented supernatant induction of ISG54 and recombinant IFN-γ stimulated ISG54 expression. Thus, IRF3 in APCs and T cells is required for optimal T-cell effector function and the ability of T cells to influence innate immune function of APCs.
Keywords: Dendritic cells; Granzyme-B; Innate immunity; Interferon Regulatory Factor-3; Interferon stimulated gene-54; Interferon-γ; Interleukin-17; T cells.
Copyright © 2016 Elsevier Inc. All rights reserved.