Members of the interferon regulatory factor (IRF) family of DNA binding transcription factors have roles in growth regulation, antiviral responses, and transcriptional induction of interferon (IFN)-activated early response genes. The IRF family member ISGF3 gamma is the DNA binding component of IFN-stimulated gene factor 3 (ISGF3), a multicomponent complex responsible for the stimulation of IFN...

Production of type I interferon (IFN; IFN-alphabeta) increases host susceptibility to Listeria monocytogenes, whereas type II IFN (IFN-gamma) activates macrophages to resist infection. We show that these opposing immunological effects of IFN-alphabeta and IFN-gamma occur because of cross talk between the respective signaling pathways. We found that cultured macrophages infected with L. monocyto...

The capacity of different cytokines to upregulate major histocompatibility complex (MHC) expression on murine tumor cells in vitro, and on s.c. tumors or pulmonary metastases in vivo has been examined. Interleukins-1, -2, and -4 (IL-1, -2, -4), tumor necrosis factor-alpha (TNF-alpha), alpha-interferon (IFN-alpha), and gamma-interferon (IFN-gamma), were incubated with tissue culture lines of mur...

Antibody neutralization studies have established interferon gamma (IFN-gamma) as a critical mediator of endotoxic shock. The advent of IFN-gamma receptor negative (IFN gamma R-/-) mutant mice has enabled a more direct assessment of the role of IFN-gamma in endotoxin (lipopolysaccharide [LPS]-induced shock. We report that IFN gamma R-/- mice have an increased resistance to LPS-induced toxicity, ...

PKR, an interferon (IFN)-inducible protein kinase activated by double-stranded RNA, inhibits translation by phosphorylating the initiation factor eIF2alpha chain. We show that human IFN-gamma mRNA uses local activation of PKR in the cell to control its own translation yield. IFN-gamma mRNA activates PKR through a pseudoknot in its 5' untranslated region. Mutations that impair pseudoknot stabili...

Lumin was orally administered to mice daily for 3 d, and on the day following the final administration, mice were sacrificed and splenocytes were stimulated with lipopolysaccharide (LPS). Splenocytes obtained from lumin-treated mice showed enhanced production of interferon gamma (IFN-gamma) and increased percentages of CD3+ cells. Although T cells are considered to be the source of IFN-gamma, i...

Interleukin-4 (IL-4) and interleukin-10 (IL-10) were evaluated for their ability to inhibit the production of nitric oxide (NO) by interferon-gamma (IFN-gamma)- or lipopolysaccharide (LPS)-activated murine macrophages (RAW 264.7 and J774.2). Macrophages pre-treated with IL-4 and then stimulated with IFN-gamma or LPS showed significant inhibition in their ability to produce NO as measured by nit...

Total saponin of heat-processed ginseng (TSHG) stimulated the production of nitric oxide (NO) in interferon-gamma (IFN-gamma)-primed macrophages through the increased expression of inducible nitric oxide synthase (iNOS). However, TSHG by itself had a very weak effect on the NO synthesis without IFN-gamma priming. The saponins of white ginseng inhibited the NO production in lipopolysaccharide (L...

Listeria infection results in the induction of gamma interferon (IFN-gamma)-producing T lymphocytes. Blocking of the costimulatory molecule B7 in vivo led to a marked decrease in antigen-specific production of IFN-gamma and interleukin-2 by lymphocytes. Blocking of both B7-1 (CD80) and B7-2 (CD86) was required in order to inhibit cytokine production, indicating that either molecule could act al...

Evidence from in vitro studies suggests that gamma interferon (IFN-gamma) and nitric oxide (NO) are important in host defense against the protozoan parasite Entamoeba histolytica. We used SCID mice with targeted disruption of the IFN-gamma receptor gene and mice with targeted disruption of the gene encoding inducible NO synthase to show that IFN-gamma plays a role in the innate immunity to ameb...