Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UMLS:C0038362 (
stomatitis
)
8,852
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The IFN-tau are type I IFN expressed by the early trophoblast of cattle and sheep but have activity on human cells and have been predicted to have potential therapeutic value. We have compared a series of mutant bovine and ovine IFN-tau with regard to their ability to inhibit the proliferation of Daudi cells and to evoke an antiviral (AV) response in WISH cells. Whereas Daudi cell growth was inhibited by Bo-IFN-tau1 in the 1 nM range, WISH cells were much less responsive, requiring exposure to 150 nM for protection against vesicular
stomatitis
virus. Replacement of lysines at positions 34, 107, 121, and 132 in Bo-IFN-tau, which are in regions predicted to interact with the type I receptor, led to modest but significant alterations in antiproliferative (AP) and AV activities. Replacement of the lysine residues at 160 and 164 had marked effects on biopotency, with K160 being particularly important. The different IFN-tau were able to activate the transcription factors
ISGF3
and AAF (GAF) in Daudi cells at concentrations that correlated reasonably well with their AP potencies. Stat activation occurred in WISH cells in response to approximately 2 nM Bo-IFN-tau1, but
ISGF3
formation could not be demonstrated even at the 100-fold higher IFN-tau concentrations that gave viral protection. Pretreatment of WISH cells with Hu-IFN-gamma allowed
ISGF3
formation to be observed in response to subsequent treatment with Bo-IFN-tau1 or type I human IFN but did not increase the AV responsiveness of the cells. No evidence was found that IFN-tau elicit uniquely different responses on human cells than type I Hu-IFN, except they are much less potent. The data emphasize the importance of a region near the carboxyl terminus for the functional activity of type I IFN, and that although ISFG3 formation may be necessary, its mere presence is not sufficient to provide an antiviral response.
...
PMID:The antiproliferative and antiviral activities of IFN-tau variants in human cells. 945 65
During pregnancy, trophoblast cells of the placenta contact maternal immune cells and yet are protected from attack. One mechanism that may account for this is that trophoblasts show altered expression of major histocompatibility complex (MHC) antigens. The gene for human leukocyte antigen G (HLA-G), a nonclassical gene, is expressed at high levels in trophoblast. Unlike other MHC class I genes, the HLA-G gene lacks an interferon (IFN) response element. Moreover, we demonstrate here that IFN, which regulates classical MHC class I genes in other cell types, does not affect these genes in trophoblast, owing to inactivation of an IFNalpha signaling pathway. Trophoblast cells (JEG-3 and JAR) were found to be selectively refractory to IFN. Specifically, although IFNalpha induced the transcription factors STAT1, STAT2, and IFN regulatory factor-1, and a protective response against encephalomyocarditis virus, it failed to protect the cells from vesicular
stomatitis
virus, activate a transfected MHC class I gene promoter, and induce the transcription factor IFN-stimulated gene factor (ISGF)-3. The lack of
ISGF3
DNA-binding activity apparently was due to diminished p48/ISGF3gamma subunit activity since
ISGF3
DNA-binding activity and IFNalpha induction of MHC class I promoter activity were reconstituted by p48/ISGF3gamma supplementation. These data indicate that a specific IFN signaling pathway is inactive in JEG-3 trophoblast cells because of altered activity of p48/ISGF3gamma, and they suggest IFN insensitivity as a mechanism that may help promote feto-placental survival.
...
PMID:Defective induction of the transcription factor interferon-stimulated gene factor-3 and interferon alpha insensitivity in human trophoblast cells. 991 96
Alternative splicing leads to the expression of multiple isoforms of the subunits (IFNAR1 and IFNAR2) of the type I IFN receptor. Here we describe two transcripts representing extracellular forms of ovine IFNAR1 and show that soluble extracellular forms of both IFNAR2 and IFNAR1, prepared in recombinant form in Escherichia coli, have antiviral (AV) activity in the absence of IFN. Exposure of Madin-Darby bovine kidney cells to the extracellular domain (R2E) of IFNAR2 at concentrations as low as 10 nM afforded complete protection against vesicular
stomatitis
virus and led to the rapid activation of the transcription factors
ISGF3
and GAF. Although R2E can bind IFN (K(d) approximately 70 nM), activity was observed irrespective of whether or not ligand was present. R2E was inactive on mouse L929 cells but active on L929 cells expressing a membraneanchored, ovine/human chimeric IFNAR2 with an ovine extracellular domain. The data suggest that AV activity is conferred by the ability of soluble R2E to associate with the transfected IFNAR2 subunit rather than resident murine IFNAR1. Soluble extracellular forms of IFNAR1 have lower AV activity than R2E on Madin-Darby bovine kidney cells but are less species-specific and protect wild-type L929 cells as efficiently as the transfected cell line, presumably by interacting with one of the murine receptor subunits.
...
PMID:Antiviral activities of the soluble extracellular domains of type I interferon receptors. 1134 74