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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hepatic granulomas induced by a single or several subcutaneous injections of carbon tetrachloride (CCl4) in Balb/c mice were examined electronmicroscopically and immunocytochemically. Stellate cells (fat-storing cells; lipocytes; Ito cells) were identified by the detection of cytoplasmic desmin, while T-lymphocytes and monocytes/macrophages were identified with monoclonal antibodies Thy 1.2 and MOMA-2, respectively. Following pericentral necrosis induced with CCl4, clear foci containing lymphocytes, monocytes, macrophages and perisinusoidal stellate cells occurred in the surrounding hepatic parenchyma on day 5. These clear foci developed to granulomas with increasing numbers of macrophages and stellate cells. Mitotic and apoptotic figures in randomly distributed macrophages, and direct contacts between macrophages and stellate cells were frequently seen within the granulomas. The stellate cells were characterized by a well-developed granular endoplasmic reticulum and Golgi complex. Collagen fibrils were closely applied to the stellate cells and connective tissue septa extended between neighboring granulomas and/or the pericentral necrotic areas after several injections of CCl4. CCl4-induced hepatic granulomas provide a model for investigating paracrine and/or autocrine modulation within a well-organized microenvironment during progressive hepatic inflammation and fibrosis.
Virchows Arch B Cell Pathol Incl Mol Pathol 1993
PMID:Granuloma formation in the liver of Balb/c mice intoxicated with carbon tetrachloride. 828 21

Collagen fibrils are generally assumed to be cylinders with uniform diameters (except possibly at their ends) and to be composed of molecules all of which have the same polarity. These assumptions have been largely untested because of the extreme difficulty associated with isolating entire native fibrils. Intact collagen fibrils are readily extracted from certain echinoderms, however, and we have therefore analyzed the molecular structure of these fibrils. Our electron microscopic analyses show the above assumptions to be false: echinoderm fibrils, which previously have been shown to be symmetrically spindle shaped, are also molecularly bipolar. Their constituent molecules have their N-termini oriented toward the nearest fibril end, and they are antiparallel in the fibril center. The shape and molecular arrangement of these fibrils have implications for fibrillogenesis.
J Mol Biol 1994 Jan 07
PMID:Native collagen fibrils from echinoderms are molecularly bipolar. 828 66

The surface of the fish pathogen Aeromonas salmonicida is covered by a paracrystalline array (the A-layer) which is a virulence factor for the organism. Quantification of the ability of A. salmonicida cells to bind collagen types I and IV in a 125I-radiolabelled liquid-phase assay showed that A-layer-positive cells bound high levels of collagen type IV, but significantly lower levels of collagen type I. Collagen type IV binding was confirmed using non-radiolabelled enzyme-linked immunosorbent assays. 125I-Collagen type IV binding was rapid, specific, saturable, high affinity, and essentially irreversible by unlabelled collagen type IV. The A-layer was responsible for collagen type IV binding because binding was inactivated by selective removal of the A-layer at pH 2.2, and neither isogenic A-layer-deficient A. salmonicida mutants nor strains of Aeromonas hydrophila possessing a morphologically similar paracrystalline array bound this basement membrane protein.
Mol Microbiol 1993 Feb
PMID:High-affinity binding of the basement membrane protein collagen type IV to the crystalline virulence surface protein array of Aeromonas salmonicida. 845 75

The equilibrium swelling of biopolymer loaded polyacrylamide gels can yield information on polymer-polymer interactions. Using the temperature dependence of excess equilibrium swelling, equations were derived to yield homopolymer as well as heteropolymer interactions. Hyaluronan and collagen (Type I) encapsulated in polyacrylamide gels showed increasing isothermal swelling with increase in the bipolymer concentration. The pH dependence of isothermal swelling caused by hyaluronan indicated that the swelling was largely due to repulsion of the charges of the carboxylate groups. Temperature dependent studies showed a decrease in swelling with an increase in temperature for collagen. The opposite trend was found for hyaluronan. This indicates that the interactions among collagen monomers are largely hydrophobic, while the interactions among hyaluronan molecules are mainly hydrogen bonding and repulsive ionic forces. Combined hyaluronan and collagen in polyacrylamide gels demonstrated an increase in swelling with an increase in temperature albeit much reduced compared with hyaluronan alone. Collagen interacts with hyaluronan through ionic attraction.
Res Commun Mol Pathol Pharmacol 1995 Aug
PMID:A study of collagen-hyaluronan interaction through swelling in polyacrylamide gels. 855 72

Fetal skin wounds heal without scarring, however the underlying mechanisms remain unknown. Immunohistochemical staining and biochemical studies indicate the deposition of a collagen repair matrix that is highly organized. We have previously described a unique hyaluronan associated protein-collagen complex (HA-PC) profile present during the period of scarless healing in the sheep fetus. In this study, we examined the biologic activity of this HA-PC in an in vivo model of adult rat wound repair. A total of 84 incisional and 84 excisional wounds were examined by histology, TGF-beta immunocytochemistry and computer planimetry (excisional wounds only). Planimetry of the excisional wounds demonstrated the mean wound area remaining at day 1 was 88.7% for the control and 63.6% for the treated (p<0.01). At day 2, mean wound area was 81.5% for the control and 63.6% for the treated (p<0.01). At day 4, mean wound area was 56.6% for the control and 41.9% for the treated (p<0.01). At day 7, mean wound area was 26.9% for the control and 16.8% for the treated (p<0.01). At day 14, mean wound area was 7.9% for the control and 3.4% for the treated (p<0.05). Collagen organization was judged to be greater in the treated compared to control wounds, with a mean organization score of 2.3 vs. 1.9 (p=0.0596; Wilcoxon Signed Rank Sum Test). There were significantly more neutrophils at the wound margin of the treated compared to control wounds, 4.0 vs. 2.7 (p=0.038; Paired Two Tailed Student's t-Test). There was no difference in the number of microphages at the wound margin of the treated compared to control wounds, 6.15 vs. 6.0 (p>0.05). TGFbeta1 and beta2 staining was decreased whereas TGFbeta3 staining was increased in the HA-PC treated wounds. These results suggest that compared to control wounds HA-PC treated wounds heal more quickly, with more organized collagen, more neutrophils at the wound margin and increased TGFbeta3 expression. Furthermore, these data suggest that the manipulation of scarring in adult wounds is possible by the addition of proteins present in fetal skin.
Biochem Mol Biol Int 1995 Sep
PMID:The in vivo effect of hyaluronan associated protein-collagen complex on wound repair. 865 77

Angioplasty has been reported to increase collagen content and to alter vascular collagen alpha 1(I), alpha 2(I), and alpha 1(III) mRNA levels. Collagen synthesis is tightly regulated by complex translational and post-translational mechanisms such that mRNA levels may not necessarily reflect biosynthesis. To test whether collagen subtype I and III protein levels are altered by angioplasty, we quantitatively analysed collagen I/III protein ratios at 4 weeks after balloon angioplasty. Twenty New Zealand White rabbits underwent iliac artery balloon de-endothelialization and then were placed on a 0.5% cholesterol/6% peanut oil diet for 7 weeks at which time angioplasty was performed on arteries with > or = 50% stenosis. Arteries with < 50% stenosis were not dilated and served as controls. Animals were killed 4 weeks later and hydroxyproline (OH-pro) content and subtype I/III ratios were analysed in 5-mm mid-iliac sections. OH-pro was measured by a colorimetric assay. Subtype ratios were determined by a highly quantitative two-dimensional cyanogen bromide peptide mapping method. The degree of stenosis was measured as the minimal vessel lumen diameter and calculated as a percentage stenosis compared to a proximal reference segment. Calculated collagen content (micrograms/mg tissue) was significantly higher 4 weeks following angioplasty compared to the non-dilated group (220.4 +/- 70.8 v 308.2 +/- 26.9, P = 0.04; n = 12), despite similar percentage stenosis in the primary and restenotic lesions. The ratio of collagen I/III subtype protein distribution was not significantly different in the non-dilated and angioplastied groups (4.88 +/- 1.00 v 4.70 +/- 0.82, respectively). These studies are the first to provide data on collagen I/III subtypes following angioplasty and suggest that collagen accumulation may be more important in restenosis than alteration of collagen protein subtypes.
J Mol Cell Cardiol 1996 Feb
PMID:Balloon angioplasty significantly increases collagen content but does not alter collagen subtype I/III ratios in the atherosclerotic rabbit iliac model. 872 74

Percutaneous transluminal coronary angioplasty is associated with intimal hyperplasia and extracellular matrix deposition of collagen, leading to restenosis in a significant number of cases. The purpose of the present study was to determine the effects of balloon angioplasty on extracellular matrix collagen content and collagenase activity in a porcine coronary artery restenosis model 6 weeks following balloon injury. We tested the hypothesis that in balloon-injured arteries the neointimal extracellular matrix was characterized by increased collagen content and decreased metalloproteinase activity relative to non-injured arteries. Male miniswine maintained on a high cholesterol diet underwent cardiac catheterization and double balloon injury to the right and left circumflex coronary arteries. The coronary arteries were either pressure-perfusion-fixed and prepared for histological examination, or dissected free of adventitia for further collagen and matrix metalloproteinase studies. Collagen synthesis in balloon-injured coronary arteries was compared to non-injured arteries using Northern blot analysis and histochemical stains. Comparative studies on differences between balloon-injured and non-balloon-injured arterial matrix metalloproteinase activity were done using zymography. Balloon angioplasty arterial injury resulted in a significant increase in type I collagen mRNA expression, with increased collagen deposition in the extracellular matrix. In contrast, matrix metalloproteinase activity was markedly decreased. The results suggest that the increased neointimal extracellular matrix observed late in the injury response may be due to not only increased collagen synthesis, but also reduced degradation. The failure to achieve a balance between the synthesis and degradation of extracellular matrix collagen could serve as an important mechanism responsible for restenosis.
J Mol Cell Cardiol 1996 Apr
PMID:Extracellular matrix collagen synthesis and degradation following coronary balloon angioplasty. 873 98

The effect of short-term treatment with biosynthetic growth hormone (GH) of male dwarf rats was studied in EDL and soleus muscles. In situ hybridisation revealed that in the untreated dwarf rat collagen I, collagen III and insulin-like growth factor-I (IGF-I) mRNA is mainly expressed by fibroblasts between the muscle fibre areas. Quantitative image analysis showed that, 8 h after a single GH injection, the level of mRNA for all three genes increased compared to the untreated dwarf animal. IGF-I mRNA levels were similar in normals and untreated dwarf rats but significantly increased 8 h after a single GH injection in EDL (P < 0.01) and soleus (P < 0.001). In untreated dwarf rats, collagen I and III gene expression was significantly less than in normal animals (P < 0.001). Collagen III gene expression also increased significantly 8 h after a single GH injection, in both muscles (P < 0.01). Collagen I gene expression showed significant increases 8 and 24 h after GH treatment in EDL (P < 0.01), although the increases seen in soleus did not reach significance. The effects of multiple GH injections (one, two or four) did not appear to be additive. The results of the time course studies are consistent with an intermediary role for IGF-I in the production of collagen in muscle.
Mol Cell Endocrinol 1995 Dec 29
PMID:Growth hormone increases IGF-I, collagen I and collagen III gene expression in dwarf rat skeletal muscle. 882 94

The myocardial extracellular matrix (ECM) is composed of three important constituents: (1) fibrillar collagen, (2) a basement membrane, and (3) proteoglycans. Structural or compositional changes in these ECM components may affect left ventricular (LV) function as well as influence overall LV geometry. Accordingly, this study examined the relationship between changes in these ECM components to changes in LV function and geometry which develop with the progression and regression from supraventricular tachycardia-induced cardiomyopathy (SVT). LV function and specific components of the ECM were studied in pigs with SVT cardiomyopathy (SVT:atrially paced 240 bpm, 3 weeks; n = 7), or after a 4-week recovery from SVT cardiomyopathy (post-SVT; n = 6), and in controls (n = 7). LV fractional shortening fell by 60% and end-diastolic dimension increased by 47% with SVT compared to controls. While LV fractional shortening normalized with post-SVT, end-diastolic dimension remained 40% higher than controls. Collagen concentration fell by 22% and salt extractable collagen, which reflects collagen cross-linking, increased by 41% with SVT compared to controls. Collagen concentration increased by 20%, collagen extraction normalized, and levels of collagen type III mRNA increased by 42% with post-SVT. Isolated myocyte adhesion capacity to basement membrane substrates laminin, fibronectin, and collagen type IV were examined. SVT resulted in over a 50% reduction in myocyte adhesion for all of the basement membrane components compared to controls. A normalization in isolated myocyte adhesion capacity was observed in post-SVT. The relative content and distribution of the ECM proteoglycan chondroitin sulfate was examined using immunohistochemistry. With SVT, the density of this proteoglycan increased around individual myocytes. With post-SVT, the relative distribution of chondroitin sulfate returned to control levels. Thus, SVT cardiomyopathy was associated with reduced collagen concentration and cross-linking, diminished myocyte basement membrane adhesion capacity, and increased proteoglycans. Recovery from SVT cardiomyopathy resulted in increased collagen concentration, and a normalization of myocyte adhesion capacity and proteoglycan distribution. These results suggest that changes within the ECM are a dynamic process and accompany the LV systolic and diastolic function as well as ventricular and myocyte remodeling during the progression and regression from cardiomyopathic disease.
J Mol Cell Cardiol 1996 Aug
PMID:Cellular and extracellular remodeling with the development and recovery from tachycardia-induced cardiomyopathy: changes in fibrillar collagen, myocyte adhesion capacity and proteoglycans. 887 70

We conducted a retrospective study to assess the changes in bone marrow (BM) stromal antigenic profile and fibrosis in chronic myeloid leukemia (CML) under combined interferon-alpha (IFN) and Ara-c therapy. Bone marrow biopsies were taken before therapy and twice (at 4 and 15 months) during therapy in 10 CML patients and compared with non-CML samples. Collagen and reticulin fibrosis was assessed by histochemical methods and phenotypic changes were studied by immunohistochemistry (APAAP) with antibodies directed against endothelial cell antigens, cell adhesion molecules, and HLA-DR. It was found that: (1) BM endothelial cells in patient and in control specimens showed a specific pattern of antigen expression: high expression of FVIII and CD34 (except on sinusoids for the latter), variable expression of UEA I, and no expression of HLA-DR and E-selectin. (2) Compared to non-CML controls, CML specimens at diagnosis showed an increased reticulin fibrosis and a decreased expression of CD61 on megakaryocytes and of CD31 on vessels and hemopoietic cells. (3) Treatment did not influence BM fibrosis, the vascular content of the BM, or the expression of the antigens tested except an increase in the number of CD34+ sinusoids (5/10 patients), an increase in the number of HLA-DR+, and a decrease in the number of CD34+ hemopoietic cells (6/10). (4) On therapy, difficulty in aspiration and/or reduced BM fragment numbers were noted in 8 of 10 patients whose bone marrow was still normocellular or slightly hypercellular. In conclusion, CML samples at diagnosis showed increased fibrosis and decreased CD31 and CD61 expression compared to controls. During the period of observation, combined therapy did not modify BM fibrosis; however, an increase in CD34+ sinusoids and a decrease in CD34+ hemopoietic cells were noted.
Hematopathol Mol Hematol 1996
PMID:Evolution of bone marrow fibrosis and stromal antigenic expression in chronic myeloid leukemia on alpha interferon and Ara-C therapy. 904 64


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