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

---

Query: EC:3.1.6.4 (chondroitinase)
2,039 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The chondroitin sulphate chains of proteoglycans are not uniformly sulphated. Commonly, regions of under- and over-sulphation are found. It is probable that variability in chondroitin sulphation has physiological significance, although such structure-function relationships largely remain unexplored. Chondroitin sulphate from rat chondrosarcoma proteoglycan has been found to possess no oversulphated residues. It is primarily chondroitin 4-sulphate, although a significant proportion of unsulphated disaccharides (14%) are also present. It appears that some unsulphated disaccharides are concentrated only at the point of attachment to the linkage region (i.e. it is the major unsaturated disaccharide remaining attached to chondrosarcoma proteoglycan core produced by chondroitinase ABC digestion). This proteoglycan core binds monoclonal antibody (MAb) 3B3. Although 3B3 principally binds to 6-sulphated 'stubs' of proteoglycan cores [Couchman, Caterson, Christner & Baker (1984) Nature (London) 307, 650-652], given a high concentration of unsulphated 'stubs', it can alternatively bind to these residues. It is also evident that caution must be exercised in using MAb 3B3 to identify chondroitin 6-sulphated proteoglycans.
...
PMID:An unsulphated region of the rat chondrosarcoma chondroitin sulphate chain and its binding to monoclonal antibody 3B3. 189 87

Among a panel of monoclonal antibodies generated against monkey brain tissue, a class of antibodies was found to produce perineuronal staining of small subsets of mammalian central neurons. Three antibodies (MAbs 473, 376, 528) we report here define two different, though partially overlapping, neuronal subsets in the monkey neocortex. All 3 antibodies stain in addition certain chondrocytes. The neural immunoreactivities were lost, and the chondral immunoreactivities either lost or enhanced, after treatment of the sections with chondroitinase ABC. Independently, 3 other antibodies (MAbs 1B5, 9A2, 3B3) with established specificity to glycosaminoglycan epitopes also produced perineuronal staining of a related subset of central neurons. Immunoblot experiments with two of the antibodies revealed bands of high molecular weight. These findings indicate that certain glycosaminoglycans occur surrounding mammalian central neurons, and suggest that different neuronal subsets are associated with different combinations of proteoglycan epitopes.
...
PMID:Glycosaminoglycan-related epitopes surrounding different subsets of mammalian central neurons. 248 66

A murine monoclonal antibody (3B3) has been produced with specificity for chondroitin-6-sulfate (C-6-S) and proven binding to rodent basement membranes, presumably detecting a population of C-6-S-containing proteoglycans. Utilizing this antibody, we sought to determine whether a basement membrane chondroitin sulfate proteoglycan is present in adult, neonatal, and/or fetal skin, and if present, its ultrastructural localization. Indirect immunofluorescence was performed on human adult, neonatal, and fetal skin. To detect the antigen, specimens were pretreated with chondroitinase ABC; absence of enzyme treatment served as negative control. Chondroitin sulfate proteoglycan was detectable in linear homogeneous array along the dermoepidermal junction and within vascular (and when present, adnexal) basement membranes in both adult and neonatal skin. In fetal skin, basement membrane staining was noted as early as 54 gestational days. Indirect immunoelectron microscopy and NaCl-split skin studies were performed to ultrastructurally localize the antigen; immune deposits were detectable within the lamina densa in chondroitinase-treated skin. These findings demonstrate that chondroitin sulfate proteoglycan is present within all skin basement membranes; that it is present in the region of the lamina densa; and that similar to some other ubiquitous basement membrane antigens, it is present early in the developing fetus.
...
PMID:Chondroitin-6-sulfate-containing proteoglycan: a new component of human skin dermoepidermal junction. 327 32

Monoclonal antibodies have been used to study the presence and distribution of various components of the proteoglycan molecule in the intervertebral disc and cartilage endplate. Link protein, hyaluronic acid binding region, keratan sulphate and chondroitin 4- and 6-sulphate have been investigated in tissues from humans and other mammals. Exposure of the carbohydrate and protein epitopes was enhanced by chondroitinase and trypsin pretreatment respectively. The degree of immunoreactivity varied with location, being greater in the nucleus pulposus than the annulus fibrosus with least reactivity in the cartilage endplate. In addition, there was increased staining in the pericellular domains, particularly in adult tissues. Areas of ectopic calcification exhibited very different immunoreactivity, depending on the type of calcium salt present. Calcium hydroxyapatite deposits showed greater staining for 8A4 (link protein), while calcium pyrophosphate deposits demonstrated greater staining for 3B3(-), 7D4(-) and 3D5 than the surrounding non-calcified matrix. Staining for chondroitin sulphate isomer epitopes 3B3(-) and 7D4(-), indicative of modified chondroitin sulphate chains, was greater in human tissues of degenerate than non-degenerate appearance. This suggests that expression of these epitopes may be an indicator of disease and subsequent reparative procedures in intervertebral disc and cartilage endplate, similar to that seen in articular cartilage degeneration.
...
PMID:Proteoglycan components of the intervertebral disc and cartilage endplate: an immunolocalization study of animal and human tissues. 751 84

Variable substitutions and locations of the sulfate esters along the backbone of chondroitin/dermatan sulfate chains, combined with their carbohydrate structures, present topographies to immune systems which can be recognized as antigenic. This has led to the development of a number of monoclonal antibodies which recognize distinct epitopes in the native structures of these glycosaminoglycan chains. In some studies, the original chondroitin/dermatan sulfate proteoglycan was digested with chondroitinase enzymes before being used as an immunogen. in this case, the linkage oligosaccharides remaining bound to the core protein contain a modified (4,5-unsaturated) hexuronic acid derivative at their non-reducing ends as a result of the eliminase mechanism of the enzyme. This 'haptenic' structure is highly antigenic and has led to the development of a number of monoclonal antibodies which recognize this structure as part of their epitopes. Examples of the use of some of these monoclonal antibodies for localization of proteoglycan structures in tissue sections and on transblots are described. The precise structures are known for only a few of the native epitopes recognized by these monoclonal antibodies. Recent analytical methods have been developed for determining structures of chondroitin sulfate oligosaccharides. An example of the use of these methods to analyze the structures of the non-reducing termini of chondroitin/dermatan sulfate chains is discussed. The results show their potential value for quantifying the native epitope recognized by a monoclonal antibody, designated 3B3, which recognizes chains terminated by glucuronic acid-N-acetylgalactosamine-6-sulfate. Such methods should be useful for determining the epitope structures for other monoclonal antibodies in this class.
...
PMID:Immunology of chondroitin/dermatan sulfate. 859 49

Articular cartilage is both morphologically and biochemically heterogeneous. Its susceptibility to degenerative diseases such as arthritis and its limited repair capacity has made cartilage the focus of intense study; surprisingly, little is known of its development. Using a panel of specific antibodies, we have documented the temporal and spatial patterns of the small leucine-rich proteoglycans fibomodulin, decorin and biglycan in the developing knee cartilage of the marsupial South American opposum (Monodelphis domestica) from parturition to adulthood. The major proteoglycan of cartilage, aggrecan, can be substituted with a variety of isomers of chondroitin sulphate (CS) and keratan sulphate (KS) glycosaminoglycans. Consequently, we have used monoclonal antibodies to determine the distribution of the chondroitinase generated epitopes of CS isomers (delta di-6S and delta di-4S oligosaccharide 'stubs'). Other monoclonal antibodies (3B3[-], 7D4) were used to investigate temporal changes in the expression of specific sulphation patterns within native chondroitin sulphate chains in addition to keratan sulphate chains (5D4). We found the distributions of the small proteoglycans (PGs) to be highly dynamic during development. Both fibromodulin and biglycan appeared to specifically label early articular cartilage as opposed to epiphyseal or growth plate cartilage. All 3 small PGs become preferentially distributed to the upper half of the adult articular cartilage depth. Similarly, delta di-6S, delta di-4S oligosaccharide 'stubs', KS and epitope 7D4 were variably distributed during development but all were again preferentially located to the upper depth of the mature tissue. The epitope recognised by antibody 3B3[-] was extensively distributed in the neonate, but became more restricted to hypertrophic chondrocytes by day 19. It was not detected in the adult tissue. These data suggest that in Monodelphis, proteoglycans are preferentially synthesised and elaborated in the upper half of the tissue depth and contrasts with the patterns observed in eutherian mammals. The data also pose questions as to the functional significance of these molecules within the tissues and to the idea that global patterns of matrix components exist in mammalian articular cartilages.
...
PMID:The development of articular cartilage: II. The spatial and temporal patterns of glycosaminoglycans and small leucine-rich proteoglycans. 918 84

The type and distribution of mineral binding and collagenous matrix-associated chondroitin sulphate and dermatan sulphate proteoglycans in rabbit alveolar bone were studied biochemically and immunocytochemically, using three monoclonal antibodies (mAb 2B6, 3B3, and 1B5). The antibodies specifically recognize oligosaccharide stubs that remain attached to the core protein after enzymatic digestion of proteoglycans and identify epitopes in chondroitin 4-sulphate and dermatan sulphate; chondroitin 6-sulphate and unsulphated chondroitin; and unsulphated chondroitin, respectively. In addition, mAb 2B6 detects chondroitin 4-sulphate with chondroitinase ACII pre-treatment, and dermatan sulphate with chondroitinase B pre-treatment. Bone proteins were extracted from fresh specimens with a three-step extraction procedure: 4 M guanidine HCl (G-1 extract), 0.4 M EDTA (E-extract), followed by guanidine HCl (G-2 extract), to characterize mineral binding and collagenous matrix associated proteoglycans in E- and G2-extracts, respectively. Biochemical results using Western blot analysis of SDS-polyacrylamide gel electrophoresis of E- and G2-extracts demonstrated that mineral binding proteoglycans contain chondroitin 4-sulphate, chondroitin 6-sulphate, and dermatan sulphate, whereas collagenous matrix associated proteoglycans showed a predominance of dermatan sulphate with a trace of chondroitin 4-sulphate and no detectable chondroitin 6-sulphate or unsulphated chondroitin. Immunocytochemistry showed that staining associated with the mineral phase was limited to the walls of osteocytic lacunae and bone canaliculi, whereas staining associated with the matrix phase was seen on and between collagen fibrils in the remainder of the bone matrix. These results indicate that mineral binding proteoglycans having chondroitin 4-sulphate, dermatan sulphate, and chondroitin 6-sulphate were localized preferentially in the walls of the lacunocanalicular system, whereas collagenous associated dermatan sulphate proteoglycans were distributed over the remainder of the bone matrix.
...
PMID:Nature and distribution of chondroitin sulphate and dermatan sulphate proteoglycans in rabbit alveolar bone. 881 81

The type and distribution of sulphated proteoglycans (PGs) in the midshaft subperiosteal bone of 15-18-day embryonic chick femurs were studied immunocytochemically and biochemically, using four monoclonal antibodies (MAb 2B6, 3B3, 1B5, and 5D4). These MAb specifically recognize epitopes in chondroitin 4-sulphate (C4-S) and dermatan sulphate (DS); chondroitin 6-sulphate (C6-S) and unsulphated chondroitin (C0-S); C0-S; and keratan sulphate (KS) respectively. Immunohistochemistry showed that staining of C4-S, DS, and KS, but not of C6-S and C0-S, was limited to osteoid, the cell surface of osteocytes, and to the walls of osteocytic lacunae and bone canaliculi in 15-18-day embryonic specimens. However, no significant difference in the distribution and intensity of immunostaining was observed in these specimens. Bone proteins were extracted from fresh 18-day embryonic specimens with a three extraction procedure, 4 M guanidine HCl (GdnCl, G-1 extract), 0.4 M EDTA (E-extract), followed by GdnCl (G-2 extract), to characterize mineral binding and collagenous matrix associated PGs in E- and G2-extracts respectively. Western blot analysis of E- and G2-extracts demonstrated that chondroitinase ABC-digested PGs with a molecular weight (Mr) approximately of 45,000 containing GAGs predominantly corresponding to C4-S and/or DS, with no detectable C6-S or C0-S present in the mineral and matrix phase, whereas KSPGs having an Mr of approximately 72,000 are only present in the mineral phase. These results indicate that embryonic chick bone contains small PGs having C4-S, DS, and KS chains with preferential localization to osteoid, the cell surface of osteocytes, and to the walls of osteocytic lacunae and bone canaliculi.
...
PMID:Immunohistochemical and biochemical characterization of sulphated proteoglycans in embryonic chick bone. 935 33

Damage to the meniscus can lead to posttraumatic osteoarthritis. Early markers of joint injury and tissue disease may be useful in developing and administering clinical treatment. We investigated the effects of total medial meniscectomy on biomarkers measured serially in synovial lavage fluid each month for 3 months. Following meniscectomy in dogs, four biomarkers were evaluated: cartilage oligomeric matrix protein, keratan sulfate epitope (5D4), the 3B3(-) neoepitope of chondroitin-6-sulfate, and the 3B3(+) chondroitinase-generated epitope of chondroitin-6-sulfate. Meniscectomy led to statistically significant elevations of all four biomarkers, with levels peaking at 4 weeks. By 12 weeks, the level of the 5D4 epitope returned to the preoperative baseline level whereas that of cartilage oligomeric matrix protein, 3B3(-), and 3B3(+) remained above the baseline. Concentrations of these biomarkers in the knees not operated on did not change significantly from the baseline. The levels of cartilage oligomeric matrix protein and 3B3(-) relative to 3B3(+) remained constant in all knees. In contrast, the level of 5D4 relative to 3B3(+) declined over time in the knee operated on but remained constant in the knee not operated on. These results demonstrate a quantitative change in the molecular components of synovial fluid after meniscectomy, as well as a qualitative change evinced by an alteration in the relative proportions of these epitopes. Extensive analyses showed a strong correlation between serum levels of 3B3(-) from the femoral and cephalic veins; however, serum 3B3(-) was not correlated with synovial fluid 3B3(-). These findings support the hypothesis that the concentrations of select cartilage biomarkers in synovial fluid are altered following meniscectomy and are promising tools for objectively monitoring the induction of osteoarthritis in this model system.
...
PMID:Longitudinal characterization of synovial fluid biomarkers in the canine meniscectomy model of osteoarthritis. 1081 29

Repair of experimental articular cartilage lesions employing cultured rabbit articular chondrocytes requires a detailed knowledge of the phenotypic stability of these cells. A suitable matrix vehicle for use in chondrocyte transplantation is a much sought-after component of any transplantation paradigm. We studied the proteoglycan synthesis repertoire of young immature rabbit articular chondrocytes maintained in chick type II collagen gels or collagen gels supplemented with recombinant human transforming growth factor-beta 1 (rhTGF beta 1). Maintenance of chondrocytes in type II collagen gels increased the percentage 35SO4-labeled proteoglycans reaching equilibrium in the A1D1 or D1 fraction of CsCl density gradient when compared to chondrocytes maintained in polystyrene microwell cultures. Although rhTGF beta 1 supplementation increased the percentage of A1D1/D1 proteoglycan by chondrocytes grown on polystyrene, rhTGF beta 1 did not augment this percentage increase in A1D1/D1 when added to collagen II gels. Rabbit chondrocytes synthesized two core proteins derived from the high-density aggregatable proteoglycans. LI and LII have apparent molecular sizes of 480 kDa and 390 kDa, respectively. Both core protein forms were found in the medium fraction, but the predominant core protein form associated with the cell fraction was LI. Maintenance of chondrocytes in collagen II gels increased synthesis of both core proteins. In addition to the large core proteins, three other core proteins with properties on SDS PAGE characteristic of the small dermatan sulfate proteoglycans, biglycan and decorin, were identified. Synthesis of these core proteins was stimulated by maintenance in collagen gels. Furthermore, they were preferentially retained in the gel matrix. Chondrocytes maintained on glass or in type II collagen gels stained with monoclonal antibodies specific for chondroitin-6-sulfate, chondroitin-4-sulfate and keratan sulfate. However, while chondrocytes grown on glass slides failed to stain with monoclonal antibody 3B3 in the absence of chondroitinase ABC digestion, chondrocytes grown in collagen II gels stained intensely in the absence of enzyme pretreatment. These results were confirmed by Western blots.
...
PMID:The proteoglycan synthesis repertoire of rabbit chondrocytes maintained in type II collagen gels. 1154 22


1 2 Next >>

---