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)

Normal human glomerular basement membrane (H-GBM) was solubilized by collagenase and subjected to crossed immunoelectrophoresis with rabbit antibodies against H-GBM. Seven precipitates appeared with the mobility of alpha, beta, and gamma globulins. Only two of these precipitates might be specific for GBM, since the other precipitates disappeared after absorption of the antiserum with liver and placenta. In normal human urine one precipitate, cross-reacting with one of the H-GBM precipitates, was found; this precipitate could also be demonstrated in human placenta and liver.
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PMID:Immunological characterization of human glomerular basement membrane antigens. 5 80

A method is described that uses trypsin digestion combined with collagenase-hyaluronidase which produces a population of gap junction vesicles. The hexagonal lattice of subunits ("connexons") comprising the gapjunctions appears unaltered by various structural criteria and by buoyant density measurements. The gap junction vesciles are closed by either a single or a double profile of nonjunctional "membrane," which presents a smooth, particle-free fracture face. Horseradish peroxidase and cytochrome c studies have revealed that about 20% of the gap junction vesicles are impermeable to proteins 12,000 daltons or larger. The increased purity of the trypsinized junction preparation suggests that one of the disulfide reduction products of the gap-junction principal protein may be a nonjunctional contaminating peptide. The gap junction appears to be composed of a single 18,000-dalton protein, connexin, which may be reduced to a single 9,000-dalton peak. The number of peptides in this reduced peak are still unknown.
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PMID:In vitro formation of gap junction vesicles. 5 58

The occurrence of intracellular fibrillar material (frequently banded) has been studied in normal costal and tracheal chondrocytes of rats at various ages ranging from 1 to 90 days. The study methods have included digestion with collagenase, electron histochemical techniques and routine electron microscopy. Banded fibrillar material has been observed intracellularly in vesicles or in electron-dense bodies in perichondrial and subperichondrial chondrocytes from rats of all ages. These fibrils and extracellular collagen fibrils are partially and equally degradable by collagenase, they are positive after staining with phosphotungstic acid or with silver nitrate methenamine, and their lucency corresponds with that of collagen when they are stained only with lead citrate. They have not been observed in intracellular clefts. They, therefore, seem to be formed intracellularly and to be exocytosed subsequently. Large vesicles and electron-dense bodies seem to be derived from Golgi saccules. A mechanism whereby banded intracellular fibrils could be formed from tropocollagen molecules is postulated. The frequency of occurrence and the diameter of intracellular fibrils seems to increase with increasing age.
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PMID:Periodic fibrillar material in intracellular vesicles and in electron-dense bodies in chondrocytes of rat costal and tracheal cartilage at various ages. 5 69

Mouse spleen cells were subjected to a fractionation procedure designed to enrich for 4-hydroxy-3-iodo-5-nitro-phenylacetyl (NIP)- or DNP-specific B lymphocytes, which depended on adherence of specific cells to a layer of hapten-gelatin at 4 degrees C, recovery of bound cells by melting, and digestion of adherent antigen by collagenase. A population of cells resulted which contained 90% typical B cells and 37% of cells capable of binding a fluorescent, haptenated polymeric protein. Fractionated cells were reacted in vitro with fluorescent conjugates of the specific haptens with polymerized flagellin [NIP-polymerized flagellin (POL)-tetramethylrhodamine isothiocyanate conjugate or DNP-POL-fluorescein isothiocyanate conjugate] under a variety of conditions, with the aim of investigating the behavior of Ig receptors on B lymphocytes after exposure to antigen; Experiments were performed with immunogenic and tolerogenic concentrations of antigen. Furthermore, four experimental designs were used, namely: (a) brief labeling with fluorescent antigen followed by culture without antigen (pulse design); (b) culture in the continuous presence of fluorescent antigen (continuous-labeling design); (c) culture in the continuous presence of nonlabeled antigen followed by labeling of unoccupied receptors by fluorescent antigen (receptor status design); and (d) culture with nonlabeled antigen for 2 h followed by incubation without further antigen for 20 h and labeling with fluorescent antigen (modulation design). Further insight into receptor occupancy and distribution was gained by the use of fluorescent antihapten and antiglobulin reagents. It was found that both immunogenic and tolerogenic antigen concentrations caused rapid patching and capping of the receptors to which they attached, followed by endocytosis and probably some shedding of Ig receptors. However, a proportion of cells continued to bear some cell surface antigen for 24 h. The immunogenic antigen concentration failed to completely remove the receptor coat from the cell surface. At all stages of immunogenesis, plentiful unoccupied receptors could be demonstrated. The tolerogenic concentration nearly saturated available receptors, and in its continuous presence, only few unoccupied or antigen-occupied surface receptors could be detected after 24 h of culture. Experiments of the modulation design showed that brief incubation with the tolerogenic concentration appeared to suppress receptor resynthesis, as few new receptors could be demonstrated after 20 h of further culture without antigen. Experiments were performed to determine whether fractionated cells prepared from spleens of 8-day-old mice showed an unusual tendency for modulation, even with immunogenic antigen concentrations. They were found to behave essentially like adult fractionated cells. The results are discussed in the framework of current theories of B-lymphocyte activation and tolerization.
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PMID:Antigen-induced aggregation and modulation of receptors on hapten-specific B lymphocytes. 5 58

1. The immunological cross-reactivity between rabbit collagenases from a variety of normal and pathological sources was examined. The specific antibody raised against collagenase secreted from normal rabbit synovial fibroblasts gave reactions of complete identity with collagenases secreted from fibroblasts derived from rabbit skin, and from synovium from experimentally arthritic rabbits. 2. The rabbit fibroblast collagenase was immunologically identical with collagenases obtained from the organ culture medium of normal rabbit skin, synovium, ear fibrocartilage and subchondral bone. 3. Collagenases from the culture media of normal rabbit synovium and from hyperplastic synovium of rabbits made experimentally arthritic were identical. 4. The collagenase secreted from rabbit fibroblasts gave a reaction completely identical with that of a collagenase extracted directly from a rabbit carcinoma. 5. IgG (immunoglobulin G) from a specific antiserum to rabbit fibroblast collagenase was a potent inhibitor of the collagenases obtained from the culture media of the various rabbit cells and tissues. 6. Collagenases from human synovium and from mouse macrophages and bone were neither precipitated nor inhibited by antibodies to rabbit collagenase. 7. No immunoreactive material was found in lysates of rabbit polymorphonuclear leucocyte granules with the specific antisera to rabbit fibroblast collagenase. No evidence for inactive forms of rabbit collagenase in lysates of the rabbit synovial fibroblasts could be found, either by double immunodiffusion against the specific collagenase, or by displacement of active enzyme from inhibition by the IgG.
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PMID:Rabbit collagenase. Immunological identity of the enzymes released from cells and tissues in normal and pathological conditions. 5 76

Tissue collagenases have been implicated in corneal ulceration in human corneal disease and in ulceration of the rabbit cornea that has served as a model system. Such enzymes from the rabbit and human cornea are inhibited by metal-binding agents of the EDTA type, by thiols, and by the human serum antiprotease alpha2-macroglobulin. Determination of the relative efficacies of collagenase inhibitors indicates that EDTA and Ca-EDTA are about one hundred times more effective on a molar basis than L-cysteine and its derivatives, N-acetyl-L-cysteine and D-penicillamine. The alpha2-macroglobulin on a molar basis, is superior as an inhibitor to the metal-binding agents and thiols. Although Ca may be a necessary cofactor of the corneal collagenases, such a requirement has not been established unequivocally. Inhibition and isotope studies do indicate a requirement for Zn. Thiols are thought to inhibit corneal collagenases by binding to or removing an intrinsic metal cofactor (Zn), and/or possibly by reducing one or more disulfide bonds. Inhibition by both EDTA-type agents and thiols is largely reversible by dialysis. The human alpha2-macroglobulin appears to inhibit corneal colleagenases irreversibly by forming tight complexes with them. Ca-EDTA, cysteine, and acetylcysteine, given as eyedrops, are able to prevent or retard ulceration in the alkali-burned rabbit cornea. They appear to have some efficacy in the prevention of corneal ulceration in humans. EDTA-type compounds are quite stable under routine storage, while acetylcysteine is more stable than cysteine. EDTA is quite toxic and should not be used as eye medication. Ca-EDTA has a low toxicity, and cysteine and acetylcysteine have even lower toxicity. It is not yet certain which inhibitor has the most favorable therapeutic index for clinical use, or is the optimal mode of drug delivery known. However, the collagenase inhibitors seem to have therapeutic promise in the prevention of corneal ulceration.
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PMID:Collagenase inhibitors: rationale for their use in treating corneal ulceration. 5 40

An inactive collagenase was harvested from both serum-free and serum-supplemented fibroblast monolayer cultures in periods of active collagen synthesis. The latent collagenase did not hydrolyze collagen and did not bind the potent collagenase inhibitor alpha2-macroglobulin. Activation with trypsin imparted to the enzyme the ability to hydrolyze collagen at neutral pH in a typical manner and to form an inhibited complex with alpha2-macroglobulin. The molecular weights, determined by calibrated gel filtration, were 78,000 and 60,000 for the latent and active enzymes, respectively. The data indicate that collagenase is released from the cells in inactive form, as a zymogen.
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PMID:Synthesis and release of procollagenase by cultured fibroblasts. 5 61

Studies were performed to determine if cultured human endothelial cells synthesized basement membrane collagen. In culture, endothelial cells were attached to grossly visible membranous structures which on light microscopy were composed of ribbons of dense, amorphous material. On transmission electron microscopy, these membranous structures consisted of amorphous basement membrane, and material morphologically similar to microfibrils and elastic fibers. By immunofluorescence microscopy, these membranous structures stained brightly with antisera to human glomerular basement membrane. Cultured endothelial cells incorporated [3H]proline into protein; 18% of the incorporated [3H]proline was solubilized by purified collagenase. When endothelial cells were cultured with [14C]proline, 7.1% of the incorporated counts were present as [14C]hydroxyproline. Cultured endothelial cells were labeled with [3H]glycine and [3H]proline and digested with pepsin. The resulting fractions on analysis by SDS-polyacrylamide gel electrophoresis contained two radioactive protein peaks of mol wt 94,200 and 120,500. Both these peaks disappeared after digestion with purified collagenase. The peak of mol wt 120,500 corresponds to that of alpha1 (IV) collagen; the peak of the mol wt 94,200 probably corresponds to that of alpha1 (III) collagen. Thus, cultured human endothelial cells synthesize material which is morphologically and immunologically like amorphous basement membrane and biochemically like basement membrane collagen. Cultured endothelial cells probably also synthesize material which is morphologically similar to microfibrils and elastic fibers.
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PMID:Synthesis of basement membrane collagen by cultured human endothelial cells. 5 57

Proteases capable of activating procollagenase from gingiva and from fibroblast and macrophage monolayer cultures were harvested from homogenates of canine tumor mast cells. The mast cell proteases lysed casein and Azocoll but not native collagen. In low salt concentrations the enzymes existed at high molecular weight complexes, which were dissociated by increasing the salt concentration above 1.0 M (NaCl, KCl). Gel filtration in 1.4 M KCl separated the protease activity into three peaks, all of which activated procollagenase. Two of the enzymes showed substrate specificities (hydrolysis of p-tosyl-L-arginine methyl ester and benzoyl-tyrosine ethyl ester) and reactive center reactivities similar to pancreatic trypsin and chymotrypsin. Based on gel filtration, apparent molecular weights of 160 000 (p-tosyl-L-arginine methyl ester esterase), 90 000 (main procollagenase activator) and 36 000 benzoyl-tyrosine ethyl ester esterase) were determined. Activation of procollagenase resulted in a 18-20 000 decrease of the molecular weight. The activation was directly related to the amount of activator added within certain limits. Further addition of activator resulted in proteolytic inactivation of collagenase.
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PMID:Activation of fibroblast procollagenase by mast cell proteases. 5 9

A tissue culture procedure for in vitro cultivation of human prostatic tissue that utilizes the enzyme collagenase to disrupt the prostate specimen is described. Collagenase effectively disperses the tissue stroma into single cells which are easily separated from the largely intact glandular structures. The isolated glandular fragments then are used to initiate monolayers of prostatic epithelium in vitro.
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PMID:In vitro cultivation of prostatic epithelium. 6 Mar 4


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