Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.36 (hyaluronidase)
 4,606 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In vitro culture conditions enabling rat tracheal epithelial (RTE) cells to differentiate to mucociliary, mucous, or squamous phenotypes are described. Medium composition for rapid cell growth to confluence in membrane insert cultures was determined, and the effects of major modifiers of differentiation were tested. Retinoic acid (RA), collagen gel substratum, and an air-liquid interface at the level of the cell layer were required for expression of a mucociliary phenotype which most closely approximated the morphology of the tracheal epithelium in vivo. Large quantities of high molecular weight, hyaluronidase-resistant glycoconjugates, most likely mucin glycoproteins, were produced in the presence of RA when the cells were grown with or without a collagen gel and in submerged as well as in interface cultures. However, extensive ciliagenesis was dependent on the simultaneous presence of RA, collagen gel, and an air-liquid interface. When RA was omitted from the media, the cells became stratified squamous and developed a cornified apical layer in air-liquid interface cultures. This phenotype was accompanied by loss of transglutaminase (TGase) type II and keratin 18 and expression of the squamous markers TGase type I and keratin 13. The ability to modulate RTE cell phenotypes in culture will facilitate future studies investigating molecular regulation of tracheal cell proliferation, differentiation, and function.
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PMID:Rat tracheal epithelial cell differentiation in vitro. 768 43

A method for hyaluronidase activity measurement in various biologic samples is suggested, based on rivanol capacity to form a clot with hyaluronic acid inversely proportional to this acid depolymerization under the effect of hyaluronidase. This method sensitivity is ten times higher than that of the mucin clot method; any colorimetric or fluorometric method can be used for detection. The method has been adapted to measurements of commercial hyaluronidase preparations and of blood serum hyaluronidase activity.
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PMID:[Determination of hyaluronidase activity by the rivanol clot method]. 785 Feb 37

A human endometrial adenocarcinoma cell line (Ishikawa) has been shown to incorporate [3H]glucosamine and to secrete a radiolabeled high molecular weight compound which is excluded from a Sepharose CL-2B column. The excluded material was resistant to hyaluronidase, chondroitinase ABC, and heparinase. These findings rule out the possibility of this material being a proteoglycan. The susceptibility of this material to digestion with pronase, neuraminidase, and alkaline borohydride treatment strongly suggests that the excluded material is an O-glycosidic glycoprotein. The glycoprotein secreted by Ishikawa cells (ICGP) did not react immunologically with antibodies against either lactoferrin or fibronectin, but did react with an antibody made against tracheal mucin. Conversely, immunoblot analysis revealed that an antibody made against ICGP did not recognize hyaluronic acid, chondroitin, heparin, nasal turbinate mucin, bovine submaxillary gland mucin, lactoferrin, or fibronectin, but did recognize tracheal mucin. Analysis of ICGP amino acid and carbohydrate composition showed that it is rich in serine, threonine, glutamic acid, aspartic acid, and N-acetylneuraminic acid. In this respect, ICGP differs from other mucins, even though it is immunologically similar to respiratory mucin; hence we may consider ICGP to be a mucin-like glycoprotein. Secretion of ICGP can be modulated by Ca(2+)-ionophore and other mucus secretagogues, such as platelet activating factor, carbachol, and monocyte/macrophage mucus secretagogue, all mediators of lung inflammation. Ishikawa cells and anti-ICGP antibody may be used in studies on in vitro regulation of mucin-like glycoprotein synthesis and secretion in the respiratory tract as well as in the endometrium.
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PMID:Characterization of a unique mucin-like glycoprotein secreted by a human endometrial adenocarcinoma cell line (Ishikawa). 818 54

The respiratory tract contains macromolecules produced by various epithelia including tracheal and bronchial mucosa and submucosal glands. The objectives of this study were to elucidate and compare the growth and secretory profiles of epithelial cell cultures derived from the human tracheal (TC) and bronchial mucosa (BC) and submucosal glands (GC). Most experiments were done on third to fourth passage cultures. Secretory glycoconjugates were characterized by a combination of gel filtration and anion-exchange chromatography after enzymic digestion with hyaluronidase of [3H]glucosamine and [35S]sulphate incorporated glycoconjugates secreted into the culture medium. Intracellular mucin-like glycoproteins were characterized by immunohistochemical staining with a human monoclonal respiratory mucin antibody. Results showed that the three cell types exhibited variable growth rates and secretory profiles. Doubling times of GC, BC and TC were 53, 75 and 80 h respectively. Immunocytochemical staining with the mucin antibody demonstrated positive reaction in GC and BC; TC showed no significant reaction. Mucin-like glycoproteins were detected in the spent media of GC and BC whereas TC, under the same conditions, did not produce any detectable amount of the glycoconjugates. Further, the mucin-like materials produced by GC and BC differed in their relative glycosylation and sulphation levels. The production of mucin was independent of substrate and vitamin A as the cultures were propagated on the plastic surfaces and the culture medium lacked vitamin A.
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PMID:Differences in secretory profiles of epithelial cell cultures derived from human tracheal and bronchial mucosa and submucosal glands. 826 31

The extracellular group B streptococcal enzyme described in numerous reports as a neuraminidase is really a hyaluronidase. Over the past 25 years, the enzyme was routinely assayed with bovine submaxillary mucin as the substrate and by the thiobarbituric acid procedure to measure released sialic acid. Characterization of the actual compound released by the enzyme revealed it to be an alpha,beta-unsaturated derivative of hyalobiuronic acid that was derived from hyaluronic acid contaminating the mucin preparation. Previous reports describing an association of elevated levels of extracellular neuraminidase with virulent strains of group B streptococci must be reevaluated with the recognition that the enzyme is really a hyaluronidase.
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PMID:Group B streptococcal neuraminidase is actually a hyaluronidase. 833 55

Previous studies have suggested that mucin gene expression is tissue-specific; however, the relationship between unique mucin gene products and the biochemical properties of mucins is unknown. The purpose of this study was to determine the biochemical and molecular characteristics of mucin synthesized by adenocarcinoma cell lines derived from breast (ZR-75-1), stomach (MGC-803), pancreas (Capan-2), and lung (Chago K-1). Mucin was quantitated by [3H]glucosamine labeling and Sepharose CL-4B chromatography. The mucinous nature of the labeled high molecular weight glycoproteins (HMG) was verified by alkaline borohydride treatment, cesium chloride density gradient ultracentrifugation, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Specific mucin gene expression was determined using cDNA probes for 2 distinct intestinal mucins (MUC-2 and MUC-3) and one breast cancer mucin (MUC-1). Specific core mucin proteins were confirmed by immunoblots using antibodies that recognize MUC-1, MUC-2, and MUC-3 core peptides. These experiments demonstrate that all cell lines contained HMG in the medium, cytosol, and membrane fractions. The HMG was mucinous in breast, pancreatic, and lung cell lines. In contrast, most of the HMG secreted by the gastric cell line was proteoglycan-like, due to its susceptibility to hyaluronidase, heparinase, and chondroitinase avidin-biotin complex. Ion-exchange (DEAE-Sephacel) chromatography of [3H]glucosamine-labeled HMG demonstrated that the acidic or basic nature of the mucin was different in all cancer cell lines tested. Despite these differences, mRNA and immunoblot analysis suggest that all cell lines predominantly express MUC-1 apomucin, small amounts of MUC-2 apomucin, and no MUC-3. Immunoprecipitation of MUC-1-type mucin using the 139H2 monoclonal antibody demonstrated that different sizes of mucin peptides were present in all cell lines, corresponding to the known length polymorphism of this mucin. The amount and nature of carbohydrate epitopes were analyzed by immunoblots using anti-T (peanut lectin), anti-Tn (91S8 monoclonal antibody), and anti-sialosyl Tn (JT10e monoclonal antibody). T and Tn antigens were significantly higher in breast and pancreatic cells as compared with lung and gastric cell lines. These findings correlated with increased activities of polypeptidyl N-acetylgalactosaminyl transferase and beta-1,3-galactosyltransferase.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Mucin synthesis and secretion in various human epithelial cancer cell lines that express the MUC-1 mucin gene. 844 22

Pathologists routinely use histochemistry, immunohistochemistry, and electron microscopy to differentiate epithelial mesotheliomas from pulmonary adenocarcinomas. Epithelial mesotheliomas are usually mucicarmine-, PAS-diastase, and carcinoembryonic antigen-negative, whereas about 60-75% of pulmonary adenocarcinomas are mucicarmine- and PAS-diastase-positive, and about 90% express polyclonal carcinoembryonic antigen. During a pathologic evaluation of pleural neoplasms between 1975 and 1990, 10 epithelial mesotheliomas were identified that were mucicarmine- and in some instances PAS-diastase-positive (diagnosis of mesothelioma confirmed by ultrastructural examination), with four mesotheliomas focally expressing carcinoembryonic antigen. The mucicarmine, PAS-diastase, and carcinoembryonic antigen staining were usually eradicated or reduced in intensity by pretreatment of the tissue sections with hyaluronidase, suggesting that hyaluronic acid was responsible for the positive mucin reactions. In three cases the epithelial mesotheliomas showed focal regions of mucicarmine, PAS-d-, and Alcian blue-hyaluronidase-resistant staining. In contrast, 10 mucicarmine-, PAS-diastase-, Alcian blue-, and carcinoembryonic antigen-positive pulmonary adenocarcinomas were not affected by hyaluronidase pretreatment of the tissue. Besides the usual ultrastructural features of well- to moderately well-differentiated epithelial mesotheliomas, the mucin-positive epithelial mesotheliomas often showed medium-electron-dense secretory material covering the microvilli, aggregates of medium electron-dense material in association with the microvilli, producing an ultrastructural morphology that has been observed only in epithelial mesotheliomas.
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PMID:Mucin-positive epithelial mesotheliomas: a histochemical, immunohistochemical, and ultrastructural comparison with mucin-producing pulmonary adenocarcinomas. 883 37

A 71-year-old asbestos-exposed male with symptoms suggestive of asbestosis for the previous 8 years presented with abdominal distension and ascites. Clinically, a diagnosis of mesothelioma carcinoma was made. Light microscopy of an omental biopsy failed to advance the diagnosis: The tumor was a solid, papillary, and glandular neoplasm lacking mucin and hyaluronidase-sensitive Alcian blue staining material. Immunohistochemistry gave positive results for Ber-EP4, LeuM1, and CEA, markers, favoring carcinoma. Electron microscopy revealed processes in channels and lumina, which were long, slender, and uncoated with a length: diameter ratio of 19.7. A few possessed small rootlets. A glycocalyx and glycocalyceal bodies were not seen. Other features included tonofibrils, a basal lamina, and desmosomes. The patient died 3 months following the onset of abdominal symptoms. Autopsy findings included solid and papillary tumor throughout the peritoneum, but no intrinsic tumor of the gastrointestinal tract or elsewhere. Arriving at a final diagnosis was complicated by immunohistochemistry, which favored carcinoma, and ultrastructure, which suggested mesothelioma. Taking into account all lines of evidence, it was concluded that the tumor was probably a mesothelioma but one with some features developed to an extent more typical of carcinoma.
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PMID:Malignant epithelial mesothelioma of the peritoneum: observations on a problem case. 883 40

Excessive production of airway mucus is a characteristic feature of many chronic inflammatory lung diseases. Although current pharmacological approaches to excessive mucus production are limited, glucocorticoids appear to be the most effective among a few useful drugs. The exact evidence for the effectiveness of glucocorticoids on mucus production has not been fully elucidated to date. The purpose of this study is to clarify the effect of dexamethasone on mucus production and mucin gene expression in a human pulmonary mucoepidermoid carcinoma cell line (NCI-H292). NCI-H292 cells produced hyaluronidase-resistant high-molecular-weight glycoconjugates (HMWG), which elute in the void volume on Sepharose CL-4B column chromatography. Dexamethasone significantly suppressed the basal production of [3H]glucosamine-or [3H]serine-labeled HMWG in NCI-H292 cells. In Northern blot analysis, dexamethasone attenuated steady-state mRNA levels of MUC-2 and MUC-5AC mucin genes. These data indicate that dexamethasone suppresses the basal production of HMWG and decreases steady-state mRNA levels of mucin genes in airway mucus-producing cancer cells.
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PMID:Dexamethasone suppresses mucus production and MUC-2 and MUC-5AC gene expression by NCI-H292 cells. 884 99

GSM06 is a cell line established from the stomach of transgenic mouse harboring a temperature-sensitive simian virus 40 (SV40) large T-antigen gene. 3H-labeled macromolecules produced by the cells incubated with [3H] glucosamine were characterized to examine whether or not GSM06 cells synthesize mucin (mucus glycoprotein). The GSM06 cells grew until a confluent monolayer formed at 33 degrees C (the permissive temperature for SV40 large T-antigen expression), and the 3H-labeled macromolecules appeared in both cell extract and medium during culture for at least 1 week. Unexpectedly, almost all 3H-labeled macromolecules, which were excluded from a column of Sepharose CL-4B, were identified as hyaluronan by analyses using Sepharose CL-2B chromatography, cesium trifluoroacetate equilibrium centrifugation, treatment with dithiothreitol, and trypsin, hyaluronidase, and chondroitinase ABC digestion. At a nonpermissive temperature (39 degrees C), GSM06 cells grew only slightly, but produced much more hyaluronan than at 33 degrees C. The results indicate that GSM06 cells produce not mucin, but hyaluronan, and that the expression of large T-antigen may influence hyaluronan synthesis in GSM06 cells.
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PMID:Immortalized gastric epithelial cell line GSM06 synthesizes hyaluronan under the influence of simian virus 40 large T-antigen expression. 927 76


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