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

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Query: EC:3.4.24.3 (collagenase)
18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A reproducible method for isolation of mouse nasal lymphocytes was developed. The cells were released from tissue fragments of dissected mouse nose by enzyme extraction with collagenase and separated by a stepwise Percoll gradient centrifugation. The partially purified nasal lymphocyte fraction from normal BALB/c mice contained CD4+ T cells (18-23%), CD8+ T cells (7-10%) and B cells (20-38%), when analysed with a FACScan fluorescence analyser. The ratio of T to B cells and that of CD4+ to CD8+ T cells in the nasal cell fraction were about twice as high as those in Peyer's path lymphocytes. The nasal lymphocyte fraction from the mice infected with influenza virus was then characterized. The nasal lymphocytes contained a twice larger number of CD4+ and a three times larger number of CD8+ T cells than those of normal mice 7 days after infection. They produced IFN-gamma which increased after infection. They contained the cells secreting influenza virus-specific IgA and IgG antibodies 4 weeks after infection. Moreover, the nasal lymphocytes from infected C3H mice lysed the virus infected-target cells. These results suggest that this method can successfully be used for investigating cellular dynamics of mucosal immunity in the upper respiratory tract of experimental animals.
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PMID:Characterization of mouse nasal lymphocytes isolated by enzymatic extraction with collagenase. 749 Apr 57

MHC class II molecules expressed in lymphoid and nonlymphoid cells act as signal-transducer molecules. We demonstrate that engagement of MHC class II molecules on human IFN-gamma-treated fibroblast-like synoviocytes by their natural ligand, the staphylococcal enterotoxin A (SEA), selectively induces the production of interstitial collagenase over the expression of the tissue inhibitor of metalloproteinase (TIMP). Collagenase gene expression required de novo protein synthesis and was accompanied by high levels of PGE2 production, suggesting its implication in this response. Two inhibitors that affect prostaglandin biosynthesis, indomethacin and arachidonyl-trifluoromethyl-ketone, inhibited both PGE2 production and collagenase gene expression. The addition of exogenous PGE2 to inhibitor-treated cells partially restored the SEA-induced collagenase, indicating a role for PGE2 in this response. As cyclooxygenases (COX-1 and -2), cytosolic phospholipase A2 (cPLA2), and secreted PLA2 (sPLA2) are the enzymes potentially implicated in prostaglandin synthesis, their involvement in SEA-induced collagenase was investigated. The mRNA levels of COX-2 and cPLA2 rapidly increased following ligation of MHC class II molecules, while COX-1 and sPLA2 mRNA levels were unchanged and transiently depressed, respectively. SEA-induced COX-2 mRNA was translated adequately to protein, whereas cPLA2 protein level was not enhanced, but rapidly phosphorylated, a process previously linked to the enzyme activation. In conclusion, this work demonstrates a selective induction of collagenase gene expression over its natural inhibitor TIMP in human IFN-gamma-treated fibroblast-like synoviocytes mediated, at least in part, by PGE2, and provides evidence that signaling via MHC class II molecules induces the production of PGE2 through enhanced production of COX-2 and possibly activation of the cPLA2.
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PMID:Superantigen-induced collagenase gene expression in human IFN-gamma-treated fibroblast-like synoviocytes involves prostaglandin E2. Evidence for a role of cyclooxygenase-2 and cytosolic phospholipase A2. 756 Oct 55

The expression of the matrix-degrading enzymes collagenase and stromelysin is modulated by a variety of biologic and pharmacologic agents. IFN-gamma has potent effects on metalloproteinase production and therefore may play an important role in preventing excessive connective tissue degradation during inflammation and repair. We investigated the mechanisms of collagenase and stromelysin regulation by IFN-gamma in human dermal fibroblasts. IFN-gamma (300 U/ml) prevented the stimulation of metalloproteinase gene expression by IL-1 beta. In addition, incubation of fibroblasts with IFN-gamma resulted in a marked increase in cellular indoleamine 2,3-dioxygenase (IDO) mRNA, a > 90% depletion of tryptophan, and a corresponding > 30-fold increase in the tryptophan metabolite kynurenine in the culture media. Reducing the concentration of tryptophan from 25 microM to 0 markedly diminished the ability of fibroblasts to increase collagenase and stromelysin mRNA and collagenase production in response to IL-1 beta. Addition of exogenous tryptophan (25-50 micrograms/ml) to cultures that had been tryptophan depleted by pretreatment with IFN-gamma for 48 h restored the fibroblast response to IL-1 beta or PMA, but had no effect on IFN-gamma-induced HLA-DR alpha chain mRNA expression. These results indicate that inhibition of collagenase and stromelysin gene expression by IFN-gamma in fibroblasts is associated with activation of IDO and enhanced cellular tryptophan metabolism. Tryptophan degradation and ensuing tryptophan depletion may account, at least in part, for the inhibitory effect of IFN-gamma on metalloproteinase production in dermal fibroblasts.
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PMID:Inhibition of collagenase and stromelysin gene expression by interferon-gamma in human dermal fibroblasts is mediated in part via induction of tryptophan degradation. 761 20

Matrix metalloproteases (MMP) constitute a family of proteolytic enzymes degrading extracellular matrix components. Their activity is inhibited by tissue inhibitors of metalloproteases (TIMP). Previous studies have demonstrated that various cytokines can modulate MMP and TIMP gene expression. In this study, we demonstrate that interferon-gamma coordinately upregulates MMP-1 (interstitial collagenase) and MMP-3 (stromelysin-1) gene expression in cultured keratinocytes, as determined at the mRNA steady-state levels, and this effect is dependent on on-going protein synthesis. In contrast, there was no effect on TIMP-1 gene expression. Enhanced MMP-1 expression by IFN-gamma was also demonstrated at the protein level by Western analysis. Transient transfections with MMP-1 and MMP-3 promoter/reporter gene constructs revealed no response to IFN-gamma, whereas incubation of keratinocytes with this cytokine appeared to stabilize the MMP-1 mRNA, resulting in reduced turnover of the transcript. These data suggest that IFN-gamma enhances MMP gene expression at the post-transcriptional level. The altered MMP expression by IFN-gamma without concomitant effect on TIMP gene expression potentially leads to imbalance between these proteases and their inhibitors, and enhanced proteolytic activity may play a role in the remodeling of cutaneous tissue involving inflammatory processes, such as wound healing.
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PMID:Interferon-gamma coordinately upregulates matrix metalloprotease (MMP)-1 and MMP-3, but not tissue inhibitor of metalloproteases (TIMP), expression in cultured keratinocytes. 786 Oct 7

The purpose of this study was to determine how interferons alpha and gamma influence the expression of M(r) 72,000 type-IV collagenase (gelatinase A) and M(r) 92,000 type-VI collagenase (gelatinase B) genes and whether there are differences in their gene expression. Special emphasis was focused on the treatment time. Total cellular RNA from A2058 human melanoma cells treated for various time periods with IFN-alpha or gamma was analyzed by Northern- and slot-blot hybridization. Both M(r) 72,000 and M(r) 92,000 type-IV collagenase mRNAs were detectable in A2058 cells and mRNA levels for both gelatinases were significantly up-regulated in the cells treated for a short time period with either IFN-alpha or gamma. In contrast, a long-term treatment (7 days) with these drugs markedly down-regulated the genes for both gelatinase A and B. Zymographic analysis showed that human melanoma primarily secretes the gelatinase-A activity, which showed changes similar to those seen in the corresponding mRNA after the treatments with interferons. The expression of gelatinase-B activity was, however, detectable only transiently during the stimulating phase with IFN-alpha. Western immunoblot analysis showed that alterations in the levels of immunoreactive protein of gelatinase A in the cells correlated with the mRNA levels after the treatments. These findings suggest that IFN-alpha and IFN-gamma are potent regulators of both M(r) 72,000 and M(r) 92,000 type-IV collagenase/gelatinase A and B genes in human melanoma showing biphasic and parallel effects on mRNA levels of both enzymes, depending on the treatment time, and that the M(r) 72,000 metalloproteinase/gelatinase A is the predominant basement-membrane-degrading type-IV collagenase in human melanoma.
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PMID:Modulation of M(r) 72,000 and M(r) 92,000 type-IV collagenase (gelatinase A and B) gene expression by interferons alpha and gamma in human melanoma. 805 55

Monolayer cultures of renal tubular (hKEC) cells were established. These cells formed empty spheroids after 2-3 weeks of culture in a collagen gel matrix. A subcellular polarity from the apex to basement was induced in these "spheroidal" hKEC cells. The weak expression of laminin at the outer surface was evident on spheroidal but not on monolayered hKEC cells. The regulation of HLA-ABC, DR, and intercellular adhesion molecule-1 (ICAM-1) antigens on hKEC cells in the gel matrix was investigated utilizing digestion of gel matrix by collagenase. Enzymatic digestion of the collagen gel did not significantly affect the surface expression of HLA-ABC and ICAM-1, but reduced HLA-DR expression as shown by flow cytometry. The MHC and ICAM-1 molecules on both spheroid-forming and monolayered hKEC cells were upregulated by adding a supernatant of mixed lymphocyte reaction (MLR) and recombinant human interferon (IFN)-gamma. HLA-DR antigen expression was inconsistently induced on the hKEC cells cultured in collagen gel without MLR supernatant or IFN-gamma. In contrast, no HLA-DR expression was found on monolayered hKEC cells in the absence of MLR supernatant or IFN-gamma. Spheroid-forming hKEC cells, when dispersed by enzymatic digestion, were more susceptible to cytolysis by lymphokine-activated killer (LAK) cells than were the enzymatically dispersed, monolayered cells in the 51Cr-release assay. The LAK cells were seen to migrate into the collagen gel and kill the hKEC cells. Thus, LAK cells may function to favor the acceleration of graft rejection.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Susceptibility of renal tubular cells to lymphokine-activated killer (LAK) cells: application of culture system using a collagen gel matrix. 809 21

We recently described mutual antagonism between IFN-gamma and TNF-alpha on human fibroblast-like synoviocytes (FLS). TNF-alpha inhibits IFN-gamma-induced HLA-DR expression and IFN-gamma blocks TNF-alpha-dependent synoviocyte proliferation, collagenase production, and GM-CSF secretion. To study the mechanism of antagonism we have analyzed the effect these factors on the expression of cytokine surface receptors. 125I-Labeled cytokine binding was measured on cultured FLS and the results were analyzed by Scatchard plots. Unstimulated synoviocytes expressed 9300 +/- 1560 IFN-gamma binding sites per cell. A single class of high-affinity receptor was observed (Kd = 4.5 +/- 2.5 x 10(-10) M). TNF-alpha did not competitively inhibit 125I-IFN-gamma binding. When FLS were incubated with TNF-alpha (100 ng/ml), there was a paradoxical 49.5 +/- 5.6% increase in the number of binding sites for IFN-gamma (P = 0.001), with no change in the Kd. Unstimulated FLS also expressed 2850 +/- 700 TNF-alpha receptors per cells, with a single Kd consistent with the lower-affinity TNF-alpha receptor (7.4 +/- 0.2 x 10(-10) M). IFN-gamma did not directly interfere with TNF-alpha binding. Preincubation of FLS with 100 U/ml of IFN-gamma resulted in a 28.9 +/- 9.0% increase in TNF-alpha receptor expression (P < 0.008), with no change in the Kd. Low levels of the soluble 55-kD TNF receptor were detected in FLS supernatants. IFN-gamma did not effect soluble TNF receptor production.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Mutual antagonism between interferon-gamma and tumor necrosis factor-alpha on fibroblast-like synoviocytes: paradoxical induction of IFN-gamma and TNF-alpha receptor expression. 839 45

Human vascular endothelial cells (HUVEC) exhibit various immunological functions, i.e. expression of HLA class-II antigens after incubation with IFN-gamma or antigen presenting function. It has also been reported that HUVEC are able to produce IL-1, IL-6, GM-CSF and immunologically active cleavage products of arachidonic acid. In our study we investigated whether various cytokines, namely IL-1, IL-2, IL-6, GM-CSF and IFN-gamma, do alter the proliferative capacity of HUVEC, the production of van Willebrandt factor (vWF) and the expression of MHC class-II antigens. HUVEC were prepared by the collagenase digestion of human umbilical veins. Monolayers of cells were incubated with cytokines in different concentrations for 24 and 48 h. IFN-gamma inhibits the HUVEC [3H]thymidine uptake in a dose-dependent manner. Suppression of proliferation (40.1%) could be observed after 24 h incubation with 100 U IFN-gamma/ml. IL-1 was a more effective inhibitor of HUVEC proliferation (54% at 10 U/ml and 24 h incubation and 48.4% after 48 h) than IFN-gamma. IL-6 and GM-CSF showed an increasing effect on proliferation with 226% and 151% of the control group, respectively. IFN-gamma after an incubation period of 12 h and IL-1 after 24 h reduced the vWF content by about 30%. Bright MHC class-II expression was induced only by IFN-gamma. In conclusion, some of the immunoregulative cytokines might play an important role in the control of HUVEC proliferation.
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PMID:Effects of interleukin-1, -2, -4, -6, interferon-gamma and granulocyte/macrophage colony stimulating factor on human vascular endothelial cells. 850 49

End organ ischemia, fragmentation of elastic membranes, and aneurysm formation in patients with giant cell vasculitis results from an inflammation destroying the mural layers of large and medium sized arteries. Although the inflammatory infiltrate extends through all layers of the affected blood vessel, the most pronounced changes involve the intima and the internal elastic lamina. Analysis of the functional profile of tissue infiltrating CD68+ cells demonstrates that different subsets of macrophages can be distinguished. TGFbeta1-expressing CD68+ cells coproduce IL-1beta and IL-6, are negative for inducible nitric oxide synthase (iNOS), and exhibit a strong preference for localization in the adventitia. The adventitial homing of TGFbeta1+ CD68+ cells places them in the vicinity of IFN-gamma secreting CD4+ T cells which also accumulate in the exterior layer of the artery. Conversely, iNOS expressing CD68+ cells are negative for TGFbeta and are almost exclusively found in the intimal layer of the inflamed artery. The intimal-medial junction is the preferred site for 72-kD collagenase expressing CD68+ cells. Thus, TGFbeta1-producing macrophages colocalize with activated CD4+ T cells and home to an area of inflammation which is distant from the site of tissue damage but critical in regulating cellular influx, suggesting that TGFbeta1 functions as a proinflammatory mediator in this disease. iNOS- and 72-kD collagenase-producing macrophages accumulate at the center of pathology implying a role of these products in tissue destruction. These data indicate that the microenvironment controls the topographical arrangement as well as the functional commitment of macrophages.
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PMID:Correlation of the topographical arrangement and the functional pattern of tissue-infiltrating macrophages in giant cell arteritis. 883 14

Tetracyclines inhibit matrix metalloproteinases (MMP) and attenuate connective tissue degradation in a wide variety of human and animal disorders. Chemically modified tetracyclines (CMT) have been synthesized in which the antibacterial potency has been eliminated but in which the anti-MMP efficacy is retained. Nitric oxide (NO) modulates MMP synthesis and activity in mesangial cells in vitro. Therefore, we examined whether CMT inhibit iNOS gene and protein expression and NO production in cultured rat mesangial cells. Mesangial cells were maintained in media containing IFN-gamma and LPS for 24-72 h. Test media contained either no further additives or CMT-1, 3, 5, or 8 at concentrations of 1, 2.5, 5, and 10 micrograms/ml. iNOS gene and protein expression were assessed and NO production was determined by the Griess reaction. Incubation of mesangial cells with CMT-3 and CMT-8 resulted in time- and dose-dependent inhibition of NO production that was maximal at 48 h (< 20% of control) and at a drug concentration of 5 micrograms/ml (P < 0.05). Addition of CMT-1 had a modest (40%) inhibitory effect and CMT-5 did not alter NO production. The impact of CMT on NO production was directly related to their potency as collagenase inhibitors. Moreover, CMT-induced changes in NO synthesis were associated with parallel alterations in steady-state iNOS mRNA abundance and protein expression. These agents may be useful to ameliorate NO-dependent glomerular inflammation.
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PMID:Chemically modified tetracyclines inhibit inducible nitric oxide synthase expression and nitric oxide production in cultured rat mesangial cells. 895 13


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