Members of the IFN regulatory factor (IRF) family regulate gene expression critical to immune response, hemopoiesis, and proliferation. Although related by homology at their N-terminal DNA-binding domain, they display individual functional properties. The distinct properties result from differences in regulated expression, response to activating signals, and interaction with DNA regulatory elem...

Interferon regulatory factor 4 (IRF-4) plays important functions in B- and T-cell development and immune response regulation and was originally identified as the product of a proto-oncogene involved in chromosomal translocations in multiple myeloma. Although IRF-4 is expressed in myeloid cells, its function in that lineage is not known. The closely related family member IRF-8 is a critical regu...

Epstein-Barr virus (EBV) infection is associated with several human malignancies. Interferon (IFN) regulatory factor 7 (IRF-7) has several splicing variants, and at least the major splicing variant (IRF-7A) has oncogenic potential and is associated with EBV transformation processes. IRF-7C is an alternative splicing variant with only the DNA-binding domain of IRF-7. Whether IRF-7C is present un...

Recent studies implicate the interferon (IFN) regulatory factors (IRF) IRF-3 and IRF-7 as key activators of the alpha/beta IFN (IFN-alpha/beta) genes as well as the RANTES chemokine gene. Using coexpression analysis, the human IFNB, IFNA1, and RANTES promoters were stimulated by IRF-3 coexpression, whereas the IFNA4, IFNA7, and IFNA14 promoters were preferentially induced by IRF-7 only. Chimeri...

The cloning and functional characterization of a novel interferon regulatory factor (IRF), IRF-10, are described. IRF-10 is most closely related to IRF-4 but differs in both its constitutive and inducible expression. The expression of IRF-10 is inducible by interferons (IFNs) and by concanavalin A. In contrast to that of other IRFs, the inducible expression of IRF-10 is characterized by delayed...

Interferon regulatory factor-1 (IRF-1) is a transcription factor that regulates interferon-induced genes and type I interferons. Recently, studies of IRF-l-deficient mice have revealed that IRF-I regulates the induction of molecules that play important roles in inflammation, such as inducible nitric oxide synthase (iNOS) and interleukin-l beta-converting enzyme (ICE). To study the role of IRF-1...

Dendritic cells (DCs) are bone marrow (BM)-derived APCs central to both innate and adaptive immunity. DCs are a heterogeneous cell population composed of multiple subsets with diverse functions. The mechanism governing the generation of multiple DC subsets is, however, poorly understood. In this study we investigated the roles of closely related transcription factors, IFN regulatory factor (IRF...

Interferon-gamma (IFN-gamma) is a pleiotropic cytokine with potent antitumor effects, both in vitro and in vivo. The antitumor activity of IFN-gamma is mediated in part through IFN regulatory factor-1 (IRF-1) and may be blocked by IRF-2. To test our hypothesis that some tumors escape the antitumor effects of IFN-gamma by cellular changes reflected in IRF-1 and IRF-2 expression, we examined IRF-...

Interferon regulatory factor-1 (IRF-1) is a tumor-suppressor gene induced by interferon-γ (IFNγ) and plays an important role in the cell death of hepatocellular carcinoma (HCC). HCC tumors evade death in part by downregulating IRF-1 expression, yet the molecular mechanisms accounting for IRF-1 suppression in HCC have not yet been characterized. Previous studies have shown that microRNA-23a (miR...

PURPOSE IRF-5 is a direct transducer of virus-mediated and TLR-mediated signaling pathways for the expression of cytokines and chemokines which form homodimers or heterodimers with IRF-7. However, direct IRF-5-specific monoclonal antibodies (mAbs) are not available at present. These could be used to further evaluate the functions of IRF-5. In this study, we produced and characterized three mous...