Search results for "Collagenase"
showing 10 items of 45 documents
Ultrastructural evidence of collagenolytic activity in ductal infiltrating carcinoma of the human breast
1987
The stroma of ductal infiltrating carcinoma of the human breast shows characteristic and localized areas of collagen rarefaction and fragmentation. This finding has been correlated with a peculiar type of fibrillar damage, observed in a small percentage of collagen fibrils isolated in the native state from the tumour stroma. The same pattern of lesion has been reproduced in vitro by human collagenase digestion on reconstituted fibrils. No effect has been detected by other nonspecific proteases in the same system.
Partial restoration of pre-transformation levels of lysyl oxidase and transin mRNAs in phenotypic ras revertants.
1995
Neoplastic transformation mediated by ras oncogenes is associated with deregulated expression of genes encoding, for example, various proteases, lysyl oxidase, and smooth-muscle α-actin. To define the role of these genes in the initiation or maintenance of the ras-transformed state, we compared their steady-state mRNA levels in two different sets of preneoplastic fibroblast lines, ras-transformed clones, and phenotypic revertants derived from them. Compared with the preneoplastic fibroblasts, the ras-transformed derivatives exhibited elevated levels of cathepsin L (major excreted protein), transin (stromelysin I, matrix metalloproteinase–3), and collagenase I (matrix metalloproteinase–1) mR…
Use of recombinant collagenases class I and II in optimization of cell purification for tissue engineering applications
2014
Improved yield and functionality of parathyroid cells separated by using collagenase-digestion with cold pre-incubation.
2001
Preparation of cells from solid organs often induces a functional impairment due to the proteolytic cell damage by the applied digestive enzyme like collagenase, trypsin or dispase. To preserve the tissue and to enhance the yield of cells, Laue et al. reported an islet cell isolation with pre-incubation at 4 C permitting the enzyme to diffuse into the tissue and explicite activity equally throughout the whole particle. The aim of this study was to investigate whether this procedure can be applied to parathyroid glands. Therefore porcine parathyroid glands were dissected into 1 mm3 pieces. Subsequently one group of these pieces was incubated 22 h at 4 C in 2 mg/ml collagenase before activati…
Enzymatic alteration of C1q, the collagen-like subcomponent of the first component of complement, leads to cross-reactivity with type II collagen
1988
AbstractNative serum C1q, the collagenous-like subcomponent of the first component of complement, is not recognized by polyclonal anti-collagen type II antibodies. However, when purified C1q was subjected to limited proteolysis by collagenase it showed antigenic cross-reactivity with collagen type II. The same cross-reactivity was observed with hemolytically active C1q in synovial fluids of patients with rheumatoid arthritis (RA), whereas C1q from synovial fluids of patients with osteoarthritis (OA), villo-nodular synovitis and ankylosing spondylitis was not recognized by this antibody. However, incubation of synovial fluid C1q of OA patients with synovial fluid leucocytes from RA patients …
EVALUATION OF STABILITY AND ENZYMATIC ACTIVITIES OF PROTEOLYTIC ENZYMES USED IN PANCREATIC ISLET TRANSPLANTATION
2009
In pancreatic islets purification, for cell therapy applications, the major enzymes used are obtained from Clostridium hystoliticum; class I and class II collagenases (Coll-G and Coll-H). In a well defined composition Coll-G/Coll-H together enzymes working on hydrophobic amminoacid, the neutral protease (Dispase) or the thermolysin (Thermostable Neutral Protease), are used in Langerhans islets purification. By electrophoresis and gelatin zymography approaches, in combination to densitometry quantitative valuation we have compared in composition, stability and autodigestion processes C. hystoliticum collagenases, Neutral protease and Thermolysin from two different producers, Roche and Serva.…
Isolation of fibroblasts for coating of meshes for reconstructive surgery: differences between mesh types.
2009
Aims: An extensive colonization of surgical meshes with autologous fibroblasts may reduce complications. Therefore, we aimed to establish a technique that allows isolation and propagation of fibroblasts from vaginal biopsies. Using these cells we tested the applicability of several clinically applied meshes for fibroblast coating. Materials & methods: Fibroblasts were isolated from vaginal tissue after digestion with collagenase. Characterization was performed by immunostaining for cytokeratin 5, 6 and 14, smooth muscle actin and vimentin. A semiquantitative technique was applied to determine the degree of mesh coating 5 h and 5 weeks after seeding of fibroblasts. Seven meshes of diffe…
Urokinase Plasminogen Activator and Gelatinases Are Associated with Membrane Vesicles Shed by Human HT1080 Fibrosarcoma Cells
1997
Membrane vesicles are shed by tumor cells both in vivo and in vitro. Although their functions are not well understood, it has been proposed that they may play multiple roles in tumor progression. We characterized membrane vesicles from human HT1080 fibrosarcoma cell cultures for the presence of proteinases involved in tumor invasion. By gelatin zymography and Western blotting, these vesicles showed major bands corresponding to the zymogen and active forms of gelatinase B (MMP-9) and gelatinase A (MMP-2) and to the MMP-9. tissue inhibitor of metalloproteinase 1 complex. Both gelatinases appeared to be associated with the vesicle membrane. HT1080 cell vesicles also showed a strong, plasminoge…
Influence of Extracellular Matrix on the Lipogenesis of Cultured White Fat Cells.
1998
Collagenase digests from subcutaneous fat tissue of new born rats were cultured on different types of collagen gel containing 50% type I collagen, on fibronectin (Fn) or on laminin (Lm). On day 6, 17% of cells on a plastic substratum differentiated and had multilocular or unilocular cytoplasmic lipid droplets (CLDs). Cells on each type of collagen and on Lm had more CLDs than those on a plastic substratum. The extent of lipogenesis showed the following decreasing order: cells on Lm (80%), on type IV+I collagen (70%), on type I collagen (52%), on type III+I collagen (36%), on type II+I collagen (32%). On day 14, most cells on Lm became unilocular fat cells. Cells on Fn showed delipidation an…
Evidence for the presence of collagenous domains in Candida albicans cell surface proteins
1995
Rabbit polyclonal antibodies (PAbs) directed towards the amino-terminal cysteine-rich 7S domain (PAb anti-7S), the major internal collagenous domain (PAb anti-type IV), and the C-terminal noncollagenous region (PAb anti-NC1) of the type IV collagen molecule were probed by indirect immunofluorescence against Candida albicans blastoconidia and germinated blastoconidia. Most nongerminating cells and mother blastoconidia from which germ tubes originated showed strong fluorescence when PAb anti-7S was used, whereas with PAb anti-type IV, fluorescence was found almost exclusively on the surface of filamentous forms. A patched fluorescent pattern rather than a homogenous confluent fluorescence was…