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)

Murine hepatocytes, isolated by an in situ collagenase-perfusion technique and cultured in Petri dishes, were shown to form rosettes with liver-metastasizing syngeneic tumor cells. Pretreatment of the tumor cells with neuraminidase generally increased the binding, whereas pretreatment of the liver cells with neuraminidase abolished the binding completely. The tumor-cell binding may be mediated by the previously described lectin-like receptor of hepatocytes that also was sensitive to neuraminidase treatment and that bound desialylated cells better than normal cells. Anti-H-2 sera could efficiently inhibit the rosette formation of metastatic tumor cells with the hepatocytes, which points to a possible role of H-2 molecules in this interaction of neoplastic and normal cells.
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PMID:Hepatocyte-tumor cell interaction in vitro. I. Conditions for rosette formation and inhibition by anti-H-2 antibody. 737 19

Enzymes and chemicals were used to analyse the biochemical structure of the antigenic epitope recognized by GDA-J/F3 monoclonal antibody (MoAb) in the human sperm tail fibrous sheath. Treatment of sperm dried onto slides with trypsin or dispase enzymes abolished their immunofluorescence staining with GDA-J/F3 MoAb, thus indicating the proteinaceous nature of the antigen. The proteolytic cleavage of GDA-J/F3 protein by trypsin, which also caused sperm decapitation, indicated the presence of peptide bonds involving the carboxyl groups of the basic amino acids, arginine and/or lysine. The epitope was also glycosylated as demonstrated by its sensitivity to sodium metaperiodate treatment which was dose-dependent. The GDA-J/F3 antigenic epitope lacked sialic acid since pre-treatment of spermatozoa with sialidase enzyme (neuraminidase) had no effect on their reactivity with the antibody. The lack of collagenous domains in the GDA-J/F3 antigen was demonstrated by the failure of collagenase to abrogate sperm immunostaining with the MoAb. Furthermore, type VII collagen of the skin basement membrane (BM) was previously thought of as a potential target antigen for GDA-J/F3 MoAb. This was ruled out since several monoclonal and polyclonal antibodies failed to detect the antigen in the spermatozoa using immunofluorescence and Western blotting. These data, therefore, show that the target antigen for GDA-J/F3 MoAb is a non-collagenous asialo-glycoprotein, and by inference provide the first evidence for the glycosylation of the sheath proteins as another step of post-translational modification occurring during sperm tail development.
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PMID:The target antigen for GDA-J/F3 monoclonal antibody in the human sperm tail fibrous sheath is a non-collagenous asialo-glycoprotein: implications and significance. 752 22

The viscoelastic properties of culture medium obtained from confluent 3T3-L1 preadipocytes, after differentiation with isobutyl-methylxanthine and dexamethasone, were studied with a rotational Couette viscometer. In close association with adipocyte differentiation, the culture medium showed gel-like properties, in concert with an increase in viscosity. This behavior vanishes after digestion by Streptomyces hyaluronidase or chondroitinase ABC, but not after application of collagenase, pronase, trypsin, DNase, or neuraminidase, or by treatment with EDTA or mercaptoethanol, indicating that the primary substance responsible for this behavior is hyaluronic acid. The material revealed a non-Newtonian behavior with an irreversible disruption of the network by shear force at high speeds. The viscosity of the medium, containing about 1 microgram/ml of hyaluronic acid, was calculated to be similar to that of a solution containing 1.7 mg high molecular weight hyaluronic acid per milliliter of stock culture medium. The comparison of rheological properties between the culture medium and solutions of hyaluronic acid indicated the possibility of a highly organized network in the culture medium that is more complicated than a simple interaction between homologous hyaluronic acid molecules. The non-Newtonian behavior depends on the hyaluronic acid concentration in the medium as well as on the length of exposure of the 3T3-L1 cells to the isobutyl-methylxanthine/dexamethasone mixture. The results point toward the possibility of interaction between hyaluronic acid and binding proteins.
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PMID:Rheological effects of the presence of hyaluronic acid in the extracellular media of differentiated 3T3-L1 preadipocyte cultures. 768 59

The central function of the cervix to maintain pregnancy is biochemically characterized by an increased synthesis of collagen, proteins, glycosaminoglycans (GAG) and fibronectin within the extracellular matrix, thus leading to an increase of cervical volume without significant changes of cervical consistency. During the time of cervical ripening we found a marked reduction of collagen concentration, a 2.5-fold increase in GAG content, a significant fall in dermatan sulfate concentrations from 41% to 15% of total GAG content, a 12-fold increase in hyaluronate concentrations, and a marked reduction in fibronectin, demonstrated by immunhistochemical methods. Thus, the loss of collagen and sulfated GAGs may facilitate distensibility in the ripened cervix, while the significant gain in hyaluronate associated with hydratation may explain the soft and swollen consistency. In this connection increased hyaluronate concentrations and degradation of fibronectin may play a trigger role for subsequent cervical dilatation. The dramatic changes of the cervix during parturition occurring within a few hours require the rapid activation and action of catabolic enzyme systems. Our studies showed a significant increase of sialidase-, collagenase- and elastase activities during cervical dilatation. These proteinases originate from polymorphonuclear leucocytes (pml), which accumulate in cervical capillaries at the onset of labor; this is followed by a massive leucocyte infiltration of the cervical stroma at the beginning of cervical dilatation and a degranulation of the pml at further dilatation, thus releasing collagenase and other proteinases. This process is limited by the immediate post partum insudation of the cervix by plasma containing highly potent proteinase inhibitors. The clinical aim of our basic biochemical studies is to develop new concepts in the causal treatment of cervical pathology during pregnancy.
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PMID:[Biochemical principles of cervix ripening and dilatation]. 771 6

The goal of the study was to establish the age-related responses of cultured porcine pituitary cells to growth hormone-releasing factor (GRF) and(or) somatostatin (SRIF). A culture system for dispersed porcine pituitary cells was validated. Pituitaries from female pigs of various ages (90 or 110 d of gestation, newborn, 3, 6, or 24 mo old) were enzymatically dispersed with collagenase and neuraminidase, plated (200,000 cells/well), and cultured for 3 d. Plated cells were then subjected to a 4-h challenge with increasing concentrations of GRF (10(-11) to 10(-8) M), SRIF (10(-9) to 10(-6) M), or 10(-8) M of each peptide with increasing concentrations of the other. Culture media were collected and assayed for growth hormone (GH). Pituitaries were pooled so that there were four replicates per age, and treatments were assigned to quadruplicate wells. Concentrations of GH in control wells (basal GH) were maximal at 110 d of gestation and decreased thereafter (P < .01) with increasing age of swine. All peptide combinations affected the GH response (P < .05) at all ages studied, yet GRF was more potent than SRIF in eliciting a response. Age had an effect (P < .05) on the GH response to any of the treatments; younger pigs (90, 110 d of gestation and newborns) had a greater response (P < .05) than older pigs (3, 6, and 24 mo), whereas 6- and 24-mo-old pigs responded similarly in all cases (P > .1).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Validation of a culture system for porcine pituitary cells: effects of growth hormone-releasing factor and(or) somatostatin on growth hormone secretion. 809 10

The aim of this study was to establish a reproducible and quantitative liver metastasis model in mice. The in vitro colon 26 (C-26) cultured cell line was initially taken from an in vivo transplantable C-26 adenocarcinoma tumor mass using the standard enzymatic treatments, collagenase and DNAse. In vitro cultured cells x 10(4) were introduced into the portal vein of syngeneic BALB/c mice to induce liver metastases and, 3 weeks later metastatic foci were found in approximately 50% to 70% of the mice. In contrast, C-26 cells desialylated by neuraminidase (Nase) treatment greatly increased the incidence of hepatic metastases with countable hepatic colonies being found in all mice (100%). This result seems to be related to the liver-characteristic D-galactose receptors, since pre-injection with an excess amount of galactocerebroside completely prevented tumor colonization in the liver. Thus, although we cannot disregard the involvement of other adhesion molecules in this system as yet, our experimental model may become a useful tool for the analysis of hepatic metastases from colon cancer in the future.
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PMID:A successful liver metastasis model in mice with neuraminidase treated colon 26. 821 12

Black-pigmented Gram-negative anaerobic rods are found on mucosal surfaces as indigenous flora. With mucosal damage due to disease, trauma or surgery, these organisms may invade tissues and set up infection. Other important factors determining whether or not infection results include 'inoculum' size, synergy with other organisms and production of virulence factors that include capsules, lipopolysaccharide, attachment factors, proteases, collagenase, neuraminidase, and phospholipase A; also, they may have fibrinolytic and anti-phagocytic activity and may degrade complement and IgG and IgM. Pigmented anaerobes are found in all types of infections including such serious infections as bacteraemia, endocarditis, intracranial abscess, necrotizing pneumonia and necrotizing fasciitis, generally as part of a mixed infecting flora, and they play a key role in experimental mixed infections. They dominate or are prominent in infections involving organisms originating in the oropharynx, such as central nervous system, head and neck, dental and pleuropulmonary infections. Therapy of infections involving pigmented anaerobes includes surgery plus antimicrobial agents; a significant percentage of strains produce beta-lactamase. Much remains to be done to determine the relative importance of the various taxa of black-pigmented Gram-negative anaerobes and of the different virulence factors produced by them.
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PMID:The importance of black-pigmented gram-negative anaerobes in human infections. 851 64

The dominant form of human surfactant protein D (SP-D) is a multimeric collagenous glycoprotein composed of monomeric subunits that have a molecular mass of 43 kDa under reducing conditions. However, in evaluating monoclonal antibodies to human SP-D, an additional monomeric subunit was identified with a reduced molecular mass of 50 kDa. This 50-kDa variant was detected in approximately half of the samples evaluated and was found in lavage fluid from normal subjects, patients with alveolar proteinosis or idiopathic pulmonary fibrosis and in amniotic fluid. This 50-kDa variant had the same amino-terminal sequence, amino acid composition and apparent size of the carboxy-terminal collagenase-resistant fragment (20 kDa) as the 43-kDa subunit. The major difference was in the amino-terminal portion of the molecule and was due to altered glycosylation, as determined by carbohydrate staining, chemical deglycosylation, treatment with N-glycanase and neuraminidase and reduced signals for threonine at positions 5, 9 and 10 during amino-terminal sequencing. After gel filtration chromatography, the 50-kDa form was not present in the high molecular weight fraction, which is commonly used in purification of SP-D, but was found only in the smaller molecular weight fraction of monomers and trimers of SP-D. In conclusion, the 50 kDa-form of surfactant protein D is produced by post-translational glycosylation and does not form higher ordered oligomers, but its precise physiological function remains to be determined.
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PMID:A 50-kDa variant form of human surfactant protein D. 986 12

The basal lamina of high endothelial venules (HEVs) in human palatine tonsils was intensely stained with cationic colloidal iron at pH 1.5 and with aldehyde fuchsin. This basal lamina exhibited a thick and double- or triple-layered structure forming small compartments, in which many lymphocytes were aligned. Digestion with hyaluronidase or collagenase eliminated both the colloidal iron and aldehyde fuchsin stainings of the basal lamina of HEVs. Treatment with chondroitinase ABC reduced colloidal iron staining, but did not interfere with the aldehyde fuchsin staining. Digestion with neuraminidase, keratanase, or heparitinase did not eliminate either the cationic colloidal or the aldehyde fuchsin staining. Digestion with neuraminidase reduced the colloidal iron staining on the luminal surface coat of the HEV. Electron microscopy of ultrathin sections revealed that cationic colloidal iron particles were deposited on the basal lamina of the HEV. The basal laminae of ordinary blood vessels were thin and single-layered, and stained only weakly with cationic colloidal iron. The present study suggests that negatively charged sites in the basal lamina of HEV derive mainly from a proteoglycan complex containing hyaluronic acid and chondroitin sulfate, which firmly binds collagen. This topochemical feature is suggested to be involved in the fascilitating migration of lymphocytes after passage through the endothelial layer.
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PMID:Chondroitin sulfate proteoglycan at the basal lamina beneath high endothelial cells in human palatine tonsils: a light and electron microscopic study using the cationic colloidal iron method. 1183 13

This assay employs a biotinylated heparan sulfate glycosaminoglycan (HSGAG) substrate that is covalently linked to the surface of 96-well immunoassay plates. The ratio of biotin:HSGAG and the coating concentration of substrate bound to the wells have been optimized and allow removal of biotin HSGAG within 60 min of incubation at 37 degrees C in assay buffer with a standard dilution of bacterial heparitinase or platelet heparanase. Loss of biotin signal from the well surface is detected on incubation with peroxidase-streptavidin followed by color development using 3,3',5,5'-tetramethylbenzidine as the peroxidase substrate. The new assay allows specific detection of heparanase activity in multiple samples in a total time of 3 h including a 1-h substrate digestion step and is a significant improvement with regard to sensitivity, specificity, and ease of handling of multiple samples compared to other described assays. Heparanase specifically degrades the biotinylated HSGAG substrate, when used with an optimized assay buffer. A range of enzymes including collagenase, trypsin, plasmin, pepsin, chondroitinases, hyaluronidase, and neuraminidase show no effect on the substrate under optimized assay conditions. The covalent linkage of the substrate to the well prevents leaching of substrate and allows preparation and long-term storage of substrate-coated plates. The assay can be used to detect heparanase levels in clinical samples and cell culture supernatants and is ideal as a screening method for antagonists of enzyme activity.
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PMID:A multiwell format assay for heparanase. 1292 26


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