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 human umbilical cord vein model was used to study the interaction of human blood with vein intima after treatment with certain enzymes. Treatment of the intima with neuraminidase produced little in the way of morphologic change, and studies showed no increase in the retention of platelets labeled with chromium 51. Treatment of vein intima with collagenase produced severe morphologic changes, with exposure of coarse and fine subendothelial fibers, but with the retention of platelets little enhanced, as determined morphologically or radiometrically. On the other hand, treatment of vein intima with trypsin resulted in loss of endothelium in some areas, with exposure of coarse subendothelial fibers that produced a marked increase in platelet retention, as determined both morphologically and radiometrically. Exposure of the vein intima to thrombin produced apparent contraction of endothelial cells, with focal exposure of subendothelium and platelet adhesion.
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PMID:A human model for study of blood-vascular wall interactions. Effects of enzymatic treatment of intima. 625 5

All strains of Legionella pneumophila tested produced detectable levels of extracellular protease, phosphatase, lipase, deoxyribonuclease, ribonuclease, and beta-lactamase activity. Weak starch hydrolysis was also demonstrated for all strains. Elastase, collagenase, phospholipase C, hyaluronidase, chondroitinase, neuraminidase, or coagulase were not detected in any of these laboratory-maintained strains.
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PMID:Extracellular enzymes of Legionella pneumophila. 626 49

Supernatants harvested from peripheral blood mononuclear cells (PBMC) incubated either with the non-specific mitogen phytohaemagglutinin-P (PHA) or with the specific antigen tuberculin purified protein derivative for 72 h decreased collagen synthesis by dermal fibroblasts. PHA-induced mononuclear cell factors (PHA-MCF) responsible for decreases in collagen synthesis by dermal fibroblasts were localized by column chromatography on Sephacryl S-200 to fractions of 30,000-60,000 daltons. Proteolytic enzymes destroyed the activity of PHA-MCF, but after incubation with neuraminidase some activity of these factors remained. The activity of PHA-MCF was not inhibited by incubation with the monosaccharides L-fucose, L-rhamnose, N-acetylglucosamine, and alpha-methyl-D-mannoside but was partially destroyed by heating at 80 degrees C for 10 min. The factors were not mitogenic to PBMC. These factors did not appear to resemble any previously characterized factors produced by non-adherent mononuclear cells. The mechanism by which these factors decreased fibroblast collagen synthesis appeared complex. There was no detectable increase in the release of collagenase by fibroblasts, nor was a cytotoxic effect apparent. Increased PGE2 production by fibroblasts could not be related to the factor-induced decrease in fibroblast collagen synthesis.
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PMID:Mononuclear cell factors that inhibit fibroblast collagen synthesis. II. Properties of the factors. 630 50

Recent studies of hepatitis B virus suggest that polymeric human serum albumin may facilitate the attachment of the virus via albumin receptors to hepatocytes during the infectious process. If this hypothesis is correct, hepatocytes should express binding sites for polymeric albumin. We employed the red blood cell adherence test using albumin-coated red blood cells as indicator cells on frozen sections of normal human livers to demonstrate these binding sites. Hepatocytes showed binding activity for both polymeric and monomeric albumin from different species. The receptor-ligand interaction was temperature and pH dependent, Ca++ independent and not altered by mercaptoethanol treatment. The binding activity was sensitive to neuraminidase and pronase, but resistant to trypsin, lipase and collagenase digestion. These findings suggest that human hepatocytes display species-non-specific albumin binding sites, which are glycoproteins.
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PMID:Albumin binding sites of human hepatocytes. 631 67

Attempts were made to clarify the mechanism of platelet aggregation and to characterize the platelet aggregating material employing established human cancer cell lines. Eleven out of the nineteen human cancer cell lines investigated showed platelet aggregating activity. The existence of divalent cation was required for the platelet aggregation induced by HMV-1 tumor cells. The platelet aggregations induced by tumor cells (HMV-1, PC-10, 3LL) were not suppressed by specific thrombin inhibitor (MD-805). The platelet aggregating activities of tumor cells (HMV-1, M 7609) were diminished by treatment with trypsin but not with collagenase or neuraminidase. Aggregating activity was preserved with a preparation of membrane from these tumor cells, although it was abolished by heating(100 degrees C 15 min) or sonication. By SDS PAGE (autoradiography), membrane proteins with MW of 20,000 daltons which specifically bound to platelets were commonly found in cells with platelet aggregating activity (HMV-1, M 7609), but were absent in platelet non-aggregating cells (HGC-25). It is therefore concluded that platelet aggregation induced by human tumor cells does not require the coexistence of thrombin, but is evoked by direct interaction of platelets with aggregating proteins (MW 20,000 daltons) on the cell membrane.
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PMID:[Studies on platelet aggregation induced by human cultured carcinoma cell lines]. 632 1

Surface markers of human gingival fibroblasts in vitro were investigated using monoclonal and heterologous antisera against a range of cell surface antigens, together with rosetting techniques to characterize surface receptors for IgG and C3. WI-38 fibroblasts and human peripheral blood monocytes were used as control cells. Human gingival fibroblasts exhibited complement receptors and beta2-microglobulin, as did WI-38 cells. Ten per cent of the human gingival fibroblasts were positive for HLA-DR antigens and additionally exhibited a granulocyte antigen not apparent on WI-38 cells. Monolayers of the gingival fibroblasts were further exposed for short periods to varying concentrations of enzymes (trypsin, collagenase and neuraminidase), bacterial extracts (lipopolysaccharide and lipoteichoic acid) and crude supra- and subgingival plaque sonicates. Surface-marker analysis was then carried out. The most noticeable effects were obtained with Vibrio cholerae neuraminidase which enhanced C3 receptor and surface antigen expression, and supragingival plaque sonicate which depressed the expression of HLA-DR and granulocyte antigens while not affecting beta2-microglobulin expression. Trypsin reduced antigen expression to a degree, but its effects were mainly on cell adherence.
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PMID:Surface markers of human gingival fibroblasts in vitro. Characterization and modulation by enzymes and bacterial products. 633 Mar 32

We have identified three germ cell surface carbohydrate antigens that exhibit a common, stage-specific pattern of expression during spermatogenesis in the mouse. IgM-class monoclonal antibodies designated "J1," "C6," and "A5" were absorbed by adult testis, but not by any adult somatic tissue tested. In indirect immunofluorescence assays using collagenase-dissociated prepuberal and adult testicular cells, these antibodies labeled the surfaces of early and late pachytene spermatocytes and round spermatids. Gonocytes from fetal and neonatal testes were not labeled. In paraffin sections of prepuberal and adult testes, sialidase treatment exposed antigens recognized by antibodies C6 and A5 on preleptotene, leptotene, and zygotene spermatocytes located near the perimeter of seminiferous tubules. The determinants recognized by antibodies J1, C6, and A5 were characterized partially using a sugar hapten inhibition assay. The binding of J1 to adult testicular cells was inhibited specifically by N-acetylglucosamine and the binding of both C6 and A5 was inhibited by N-acetyllactosamine. The glycoconjugates recognized by J1, C6, and A5 eluted from gel filtration columns with an apparent molecular weight greater than 1 X 10(6) and were sensitive to endo-beta-galactosidase (keratanase) treatment. The apparent high molecular weight of these glycoconjugates was confirmed by immunolabeling Western blots of testis extracts separated by SDS-polyacrylamide gel electrophoresis. The results suggest that polylactosamine (keratan) glycoconjugates of high molecular weight are associated with the plasma membranes of meiotic and haploid male germ cells. The effects of sialidase on antibody labeling patterns suggest that changes in cell surface sialylation accompany the transition of early meiotic germ cells to pachytene spermatocytes during spermatogenesis.
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PMID:Stage-specific expression of three cell surface carbohydrate antigens during murine spermatogenesis detected with monoclonal antibodies. 637 Jul 56

Using the sialic acid-specific lectin, limulin (LPA; from Limulus polyphemus hemolymph), the distribution and nature of sialoglycoconjugates on the surface of rat pancreatic cells has been investigated. Binding of rhodaminated LPA (Rh-LPA) or horseradish peroxidase-conjugated LPA (HRP-LPA) to fixed-frozen sections of adult rat pancreas resulted in intense linear staining of the apical surface of acinar cells with fainter staining on the basal but not the lateral cell surfaces. LPA binding was specific in that it could be abolished by 1) pretreatment of tissue sections with neuraminidase or periodic acid; 2) competition with sialic acid; and 3) incubation in Ca2+ -free buffers. Pretreatment of sections with proteases abolished LPA binding to the apical surfaces of acinar cells and also enhanced LPA binding to the lateral cell surface. Lipid extraction of sections following protease treatment markedly reduced LPA binding to the acinar cell periphery. These results suggest that LPA binding sites on the acinar cell apical surface may be primarily sialoglycoproteins, while those on the basolateral surfaces may consist in part of gangliosides. Electron microscopy of collagenase-dispersed acini exposed to HRP-LPA confirmed binding of LPA to the basal plasmalemma and, in addition, revealed staining of basal lamina when present. LPA binding to the acinar cell surface was not affected by digestion of tissue sections with hyaluronidase, heparinase, collagenase, or 6 M guanidine-HCl. Control experiments indicated that rat pancreatic secretory proteins contain undetectable amounts of sialoglycoproteins and thus that the apical localization of LPA is not due to adherent secretory proteins. Islets of Langerhans were always uniformly and heavily stained with LPA conjugates; this staining was protease insensitive. Appearance of LPA binding sites was examined on embryonic pancreatic epithelia. At day 15 of gestation, Rh-LPA stained the entire periphery of the epithelial cells, including the lateral cell surface, although more intense staining was already noted on the apical surface. This pattern persisted through day 17 of gestation, but by day 19 an adult staining pattern was observed with loss of staining of the lateral cell surfaces.
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PMID:Distribution of sialoglycoconjugates on acinar cells of the mammalian pancreas. 675 68

Culture-produced subendothelium (SE) has been prepared from cultured porcine aortic endothelial cells (ECs) by a rapid freeze-thaw, ice-shearing method. En face preparations of this in situ SE material are essentially free of intact or damaged cells and cell debris and consisted of an extensive meshwork of microfibrillar and amorphous material. Washed porcine platelets reacted extensively with this SE material and were associated with the SE as single adherent platelets, single spread platelets, and varying-sized platelet aggregates or 'microthrombi'. Platelet aggregates were associated only with the damaged or frayed edges of the SE, and the platelets had undergone extensive SE-induced contraction and degranulation, as indicated by transmission electron microscopy. Platelet-SE interaction was affected by pH, calcium, platelet concentration, rapid shaking and exposure time. Platelet-SE interaction was significantly enhanced by the addition of 0.1-1% citrated plasma or purified porcine F.VIIIR:WF. Pretreatment of the SE with thrombin, elastase, neuraminidase or hyaluronidase had no effect on platelet-SE interaction, whereas pretreatment with pepsin, plasmin, trypsin, alpha-chymotrypsin or collagenase decreased or completely abolished all platelet-SE interaction. Extraction of the SE with various solutions (high salt, detergents, etc.) had no effect on platelet-SE interaction, only solutions containing sodium dodecyl sulfate completely abolished all platelet-SE interaction.
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PMID:Culture-produced subendothelium. I. Platelet interaction and properties. 680 25

Lymphocyte subpopulations in peripheral blood (PBL) and intestinal mucosa (IML) of 10 patients with inflammatory bowel disease (IBD) were compared with those of 11 non-IBD controls. PBL were separated on Ficoll/hypaque gradients, and IML were isolated by incubation in dithiothreitol, EDTA, and collagenase. These methods yielded cells of good viability and with intact HLA A and B-antigens. T-cells, identified by neuraminidase-treated sheep RBC rosettes and non-specific esterase staining, comprised approximately 91% of the IML from normal mucosa of all groups. B-cells, identified by erythrocyte-antibody-complement rosettes and surface immunoglobulins, were only 7% of these IML populations. Cell yields were two-fold or more greater from abnormal IBD mucosa, with T-cells ranging from 55 to 95% and B-cells from 2 to 36%. The percentage of Fc receptor bearing cells was low in all specimens. By these methods, T-lymphocytes predominated in intestinal mucosa of both IBD and non-IBD patients, but there is marked increase in the percentage of B-cells isolated from abnormal mucosa in IBD.
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PMID:Lymphocyte subpopulations of intestinal mucosa in inflammatory bowel disease. 696 6


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