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)

Studies of Sertoli cell structure, maturation, and function have been aided by the use of in vitro systems. Although numerous papers have appeared that utilize the Sertoli cell culture model, few papers have dealt with the characterization of these cells under various culture environments. Recently, it has been reported that the addition of serum to the culture medium prevents induction of long cytoplasmic appendages in cultured Sertoli cells that have been treated with FSH, TSH, or c-AMP. The purpose of this investigation was to determine which serum components, obtained by gel filtration, are capable of inhibiting the morphological response induced by FSH, TSH, or c-AMP. Sertoli cell-enriched cultures were prepared using collagenase and trypsin digestion, each followed by gravity sedimentation. Untreated cells grown on plastic or glass substrates assumed an epithelioid appearance after several days. Cells treated with FSH, TSH, or c-AMP formed long cytoplasmic appendages after 1-2 days. This response was prevented or reversed by the addition of fetal calf serum (10%), crystallized bovine serum albumin (0.25%-2%), or purified albumin obtained by gel filtration of whole serum (0.25%). It was also found that fractions that elute between the void volume and the initial albumin fractions (molecular weights of approximately 50,000 and greater) mimic the hormone-induced response after only 10-12 hours. The results of this investigation indicate that albumin is the primary serum component responsible for inhibiting morphological alterations induced by FSH, TSH, and c-AMP. Furthermore, it is apparent that the production of long filamentous cytoplasmic appendages in Sertoli cells can be induced by a wide variety of substances.
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PMID:Effects of serum components on the morphology of Sertoli cells in culture. 625 34

The soluble material produced from a 96-hour digest of sonicated human glomerular basement membranes with purified collagenase was shown to contain at least 12 components by sodium dodecyl sulphate-polyacrylamide gel electrophoresis with molecular weights ranging from 20 x 10(3) to greater than 200 x 10(3) daltons. Five of these components produced antigenic peaks after two-dimensional immunoelectrophoresis into agar plates containing rabbit antiserum to the solubilised glomerular basement membrane. Two groups of antigenic components were demonstrated in these gels by two-dimensional immunoelectrophoresis autoradiographic techniques utilising 125I-labelled collagenase-digested human glomerular basement membranes reacted with antibodies eluted at acid pH from the kidney of the Goodpasture's patient. This acid eluate was shown to contain contaminants of alpha 1-antitrypsin and albumin co-eluting with the antibodies bound to the glomerular basement membrane. After removal of these contaminants, the antibodies were linked to cyanogen bromide-activated Sepharose and used to affinity purify four antigenic fractions from the collagenase-digested glomerular basement membrane. These fractions were eluted by 0.2 M glycine pH 2.8 and with 0.5 M ammonium thiocyanate and had molecular weights of 22-25, 43-45, 65-70 and 205 x 10(3) daltons. The smaller molecular weight components were shown to be common to both included and excluded fractions obtained by Ultragel AcA 44 chromatography of the digested material in 10 mM phosphate pH 8. This suggests that the larger molecular weight component would be an aggregate of a smaller component. Preliminary carbohydrate and amino acid analyses indicated that the different elution procedures elicited antigens with different chemical characteristics.
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PMID:Isolation of human glomerular basement membrane antigens by affinity chromatography utilising Goodpasture's kidney antibody eluates. 627 70

Using EDTA extraction and collagenase digestion, rat bone and rat skin were compared in terms of their content of hydroxyproline, hexoses, uronic aicd, sialic acid and plasma proteins. The collagen content of the organic matrix from both tissues was similar. Greater differences were observed in the sialic acid and uronic acid content of the matrix, bone containing higher amounts; smaller differences were found in the levels of hexoses, albumin, IgG and alpha 1 acid-glycoprotein, which are higher in EDTA extracts from bone. The DEAE-cellulose chromatography of the EDTA extracts and soluble collagenase digests indicated the presence of a variety of glycoproteins and a proteoglycan fraction. An acidic glycoprotein, corresponding to sialoprotein, was present in bone but not in skin extracts.
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PMID:Biochemical analyses of EDTA extracts and collagenase digests from bone and skin of Wistar rats. 628 4

The study of human endothelial cells in tissue culture has been previously limited to umbilical vein, a large vessel source, and microvascular endothelium from human foreskin, spleen, and adrenal. Microvascular endothelium cultured from these sources have required matrix-coated culture flasks, tumor-conditioned medium, or 50% human serum for growth and subcultivation. To obtain cultures of microvascular endothelium with less stringent growth requirements, human adipose tissue was digested with collagenase and endothelial cells were separated from other stromal elements by sequential filtration and layering cells onto 5% albumin. Using standard medium containing 10% fetal calf serum, these cells grew readily to confluence and survived serial passages. When the cultures were subconfluent, cytoplasmic extensions and a capillary-like morphology were observed. Confluent cultures displayed the "cobblestone" appearance characteristic of other endothelial preparations. Electron microscopy demonstrated the presence of characteristic tight junctions and pinocytotic vesicles. Immunofluorescent staining for Factor VIII was positive, and cultures contained angiotensin-converting enzyme activity. Thus, cultures of human microvascular endothelium were readily obtained from adipose tissue and required only standard medium with 10% serum for growth and subcultivation. This system can be used to study human endothelial cell biology and may prove useful in the study of pathologic states such as diabetic microvasculopathy and tumor angiogenesis.
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PMID:Isolation and culture of microvascular endothelium from human adipose tissue. 630 56

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

A new method for preparing non-parenchymal rat liver cells (NPC) is described. The liver cell suspension, prepared by perfusing the liver with collagenase, was treated with enterotoxin from Clostridium perfringens for 15 min. The enterotoxin made the parenchymal cells leaky, and these cells could be separated from the NPC by centrifugation in a solution containing Nycodenz (20%, w/v). During the centrifugation, the NPC floated, while the parenchymal cells sedimented. The yield of NPC per liver (200 g rat) was about 250 X 10(6) cells. The NPC were further separated into endothelial cells, Kupffer cells and stellate cells by centrifugal elutriation. This method was particularly useful for preparing endothelial cells in high yield (100 X 10(6) cells per liver). Intravenously injected formaldehyde-treated albumin was selectively taken up by the endothelial cells. Isolated endothelial cells in suspension as well as in surface culture maintained their ability to endocytose this ligand.
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PMID:Preparation of isolated liver endothelial cells and Kupffer cells in high yield by means of an enterotoxin. 631 61

Collagen and noncollagenous proteins (NCP) have been studied in Wistar rats according to the age and sex. The total amounts of bone matrix proteins, EDTA extracts and the soluble collagenase resistant fraction (SCRF) decreases with aging while the insoluble collagenase resistant fraction (ICRF) increases. No consistent sex-differences have been observed. In the bone matrix, the sialic acid and hexose contents increase with age, the uronic acid value decreases while hydroxyproline does not change. In the EDTA extracts, the collagen extractability decreases markedly with age, the sialic acid content increases while the hexose and uronic acid contents do not vary. Plasma proteins (albumin, orosomucoid and IgG) also do not change with aging. In the collagenase digests, no age and sex differences were found in the collagen and noncollagenous proteins of the SCRF while in the ICRF a decrease was observed for hexoses, uronic acid and sialic acid and an increase for hydroxyproline from the third month onwards.
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PMID:Age and sex variations of bone matrix proteins in Wistar rats. 641 33

Fetal human hepatocytes were isolated by collagenase digestion of liver fragments and cultured either alone or mixed with rat liver epithelial cells. Whereas they did not survive more than 2-3 weeks and showed rapid morphologic and functional alterations in conventional culture, fetal hepatocytes survived and retained or reverted to a globular morphology for several weeks and showed active albumin secretion for at least 13 days when cultured with rat liver cells. Increased levels of secreted albumin correlated with deposition of an insoluble extracellular material containing fibronectin and type III collagen located principally between the two cell types and around parenchymal cells. These observations show that fetal human hepatocytes are able to interact in vitro with another epithelial liver cell type obtained from a divergent species and that these cell-cell interactions influence both hepatocyte survival and expression of albumin.
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PMID:Modulation of human fetal hepatocyte survival and differentiation by interactions with a rat liver epithelial cell line. 646 60

The isolation of Xenopus liver, lung and testis cells by collagenase digestion of the tissue, followed by Percoll density gradient centrifugation, was characterized by the preferential synthesis of two proteins whose size and charge were similar to 70 and 85 kD heat-shock proteins. The synthesis of these two heat-shock-like proteins, relative to that of total protein, declined gradually in the first 3-4 days after the cells were plated out for primary culture. In fresh primary cultures of liver parenchymal cells albumin mRNA concentration declined rapidly and plateaued at 3-4 days of culture. Freshly isolated male Xenopus hepatocytes were refractory to induction by estrogen of vitellogenin gene transcription but they reacquired hormonal response during the first 3 days of culture. Both of these differentiated phenotypic functions of the Xenopus hepatocytes were quantitatively associated with the decline in synthesis of hsp-like proteins in freshly prepared primary cell cultures. Freshly isolated or heat-shocked hepatocytes exhibited a rounded shape with little intercellular contacts, whereas during the recovery period of 3 days they acquired a flattened shape with a high degree of intercellular and cell-substratum interaction. These results present the first evidence for the preferential synthesis of heat-shock-like proteins by procedures for establishing primary cell cultures. They emphasize the necessity of monitoring normal and heat-shock protein synthesis and cell morphology before using primary cell cultures for studying normal regulatory and developmental processes.
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PMID:Culture shock. Synthesis of heat-shock-like proteins in fresh primary cell cultures. 654 Nov 49

We present a simple and improved method for in situ localization of albumin and collagen mRNAs in isolated mouse hepatocytes. The cells were isolated by collagenase perfusion, mincing, and differential centrifugation. Nick-translated 3H-labeled mouse albumin cDNA (pmalb-2) and chicken pro-alpha 2(I) collagen cDNA (pCg45) probes were then hybridized with the cells in silane-treated microcentrifuge tubes. The cells were transferred and fixed to a microscope slide and hybridization was evaluated semiquantitatively by counting exposure of grains in autoradiographic emulsion placed over the cells. With this method of in situ hybridization, all hepatocytes appear to have significant, but highly variable, amounts of albumin mRNA. In addition, type I procollagen mRNA appears to be present at low abundance in hepatocytes. These results indicate that in situ hybridization can effectively demonstrate the presence of specific low- or high-abundance mRNAs in isolated well-differentiated eukaryotic cells.
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PMID:Use of in situ hybridization to identify collagen and albumin mRNAs in isolated mouse hepatocytes. 657 92


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