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1.
This study has assessed the relative proportions of type I and II collagens and IIA procollagen in full depth biopsies of repair tissue in a large sample of patients treated with autologous chondrocyte implantation (ACI). Sixty five full depth biopsies were obtained from knees of 58 patients 8–60 months after treatment by ACI alone (n = 55) or in combination with mosaicplasty (n = 10). In addition articular cartilage was examined from eight individuals (aged 10–50) as controls. Morphology and semi-quantitative immunohistochemistry for collagen types I and II and procollagen IIA in the repair tissue were studied. Repair cartilage thickness was 2.89 ± 1.5 mm and there was good basal integration between the repair cartilage, calcified cartilage and subchondral bone. Sixty five percent of the biopsies were predominantly fibrocartilage (mostly type I collagen and IIA procollagen), 15% were hyaline cartilage (mostly type II collagen), 17% were of mixed morphology and 3% were fibrous tissue (mostly type I collagen). Type II collagen and IIA procollagen were usually found in the lower regions near the bone and most type II collagen was present 30–60 months after treatment. The presence of type IIA procollagen in the repair tissue supports our hypothesis that this is indicative of a developing cartilage, with the ratio of type II collagen:procollagen IIA increasing from < 2% in the first two years post-treatment to 30% three to five years after treatment. This suggests that cartilage repair tissue produced following ACI treatment, is likely to take some years to mature.  相似文献   

2.
Fibronectin and collagen, types I, III, IV and V, in the granulation tissue replacing the myocardial infarction, in the focal and diffuse cardiosclerosis were studied by means of the immunofluorescent method. The extracellular matrix in the granulation tissue contained fibronectin and collagen of the above types. Intracellular fibronectin was also found in the necrotized cardiomyocytes. Fibronectin and collagen of type IV were not detected in the postinfarction scars. The extracellular matrix consisted mainly of collagen, types III and V. Fibronectin and collagen, types I, III and V, are observed in the connective tissue in diffuse cardiosclerosis in the presence of the coronary arteries stenosis. No prevalence of the collagen of any type was found.  相似文献   

3.
Immunohistochemical localization of collagen types I, II, III, and IV in the pterygium was demonstrated by type-specific antibodies. The stromata of pterygium and normal conjunctival tissues contained collagen types I, II, and III, while the normal corneal stroma showed collagen types I and III but not collagen type II. Collagen type IV was located in the epithelial and capillary endothelial basement membranes of pterygium and normal conjunctival tissues. These results suggest that collagens in pterygial tissues are derived from those in the conjunctival tissues.  相似文献   

4.
Localization of fibronectin and types I, III, IV and V collagen was investigated in semithin sections of fibrous atherosclerotic plaques and apparently normal intima of human aorta. The effect of different techniques of fixation and processing of the sections on immunostaining under peroxidase-antiperoxidase techniques have been examined. The tissue fixation in paraformaldehyde solution, removing the resin with sodium ethoxide and enzymatic pronase digestion of the sections resulted in successful specific staining of the antigens. It was found that some cells in fibrous plaques formed a cap of multiple layers of dense connective tissue containing fibronectin and type III, IV and V collagen in the absence of collagen type I.  相似文献   

5.
Collagen types I, III and IV, fibronectin and elastin were detected by immunohistochemistry in the normal and copper-deficient rat heart. All rats maintained on a copper-deficient diet for at least 6 weeks were found to have areas of abnormal distribution of these connective tissue components within the endo- and perimysium although the normal appearance observed in control animals prevailed. It appeared that the proliferation of the fibrillar collagens and fibronectin was associated with fibrosis and scar tissue formation. In contrast, the fragmented and disorganized appearance of the myocyte basement membrane and the endomysial elastin did not seem to be associated with the fibrotic process and may be an early indication of copper deficiency. The vascular system of the copper-deficient hearts appeared normal. These results are discussed with reference to the functional and mechanical abnormalities that occur in copper-deficient animals.  相似文献   

6.
The distribution of types I, III, IV and V collagen and of the glycoproteins fibronectin and laminin in sections of human aortas, arteries and atherosclerotic plaques were studied using monospecific antibodies and indirect fluorescence microscopy. Types IV and V collagen and laminin were present in a narrow zone, representing the basement membrane, apposed to the endothelial layers of all these tissues. Types I and III collagen and fibronectin were located in the interstitial spaces of the intima and the media of blood vessels walls, whereas types IV and V collagen and laminin were found in the basement membranes underlying smooth muscle cells in these areas. Two types of atherosclerotic plaques were observed. Lipid-rich plaques contained less collagen and reduced amounts of the glycoproteins. Fibrous plaques consisted of regions deficient in types I and III collagen and collagen-rich regions with elevated levels of these two collagens as well as more fibronectin. The collagen-rich regions of fibrous plaques contained, however, little type IV and type V collagen and little of the glycoproteins laminin and fibronectin. This may be due to the reduced number of cells involved in the biosynthesis of these basement membrane proteins.  相似文献   

7.
The indirect immunofluorescence method was used to study the human term placenta in pathological pregnancy for the distribution of collagen types I, III, IV, V, and fibronectin in fibrosis stromatis villi. All collagen types and fibronectin were shown to participate in fibrosis villorum formation. Fibronectin was also detected in the fibrinoid that surrounded villi at stroma. The presence of free cytotrophoblast cells in the fibrinoid was accompanied by a noticeable increase in fibronectin fluorescence. A significant amount of collagen types IV and V and a less amount of collagen types I and III were identified.  相似文献   

8.
INTRODUCTION: Posterior tibial tendon dysfunction is a common cause of adult flat foot deformity, and its etiology is unknown. PURPOSE: In this study, we characterized the morphologic pattern and distribution of types I, III and V collagen in posterior tibial tendon dysfunction. METHOD: Tendon samples from patients with and without posterior tibial tendon dysfunction were stained by immunofluorescence using antibodies against types I, III and V collagen. RESULTS: Control samples showed that type V deposited near the vessels only, while surgically obtained specimens displayed type V collagen surrounding other types of collagen fibers in thicker adventitial layers. Type III collagen levels were also increased in pathological specimens. On the other hand, amounts of collagen type I, which represents 95% of the total collagen amount in normal tendon, were decreased in pathological specimens. CONCLUSION: Fibrillogenesis in posterior tibial tendon dysfunction is altered due to higher expression of types III and V collagen and a decreased amount of collagen type I, which renders the originating fibrils structurally less resistant to mechanical forces.  相似文献   

9.
After partial hepatectomy, the liver is capable of complete regeneration, restoring normal hepatic size, architecture, and function. To study the role of the extracellular matrix in regeneration, the temporal and spatial sequence of deposition of several of its components, including collagen types I, III, and IV, laminin, and fibronectin, in rat liver, after an 80% hepatectomy, was characterized by light microscopy immunohistochemistry. A minimum of five animals were studied for each date. In agreement with previous reports, subsequent to 80% hepatectomy, there was a brisk mitosis of hepatocytes. The mitotic activity was maximal at 48 hours, primarily in the periportal and centrilobular zones, and resulted in the formation of hepatocyte clusters and widening of the hepatic plates. Of the extracellular matrix components studied, laminin was the one demonstrating the most dramatic changes. By 24 hours, laminin appeared in the hepatic sinusoids reaching a maximum staining intensity at 48 hours. Intracellular laminin was prominent in numerous non-parenchymal cells, with many having the morphology, location, and desmin content characteristic of Ito cells. Laminin staining decreased in the sinusoids at 4 days; however, some intracellular staining of Ito cells was present even at 8 days after hepatectomy. At the completion of regeneration, there was no evidence of any substantial change in the ratio: extracellular matrix/cell mass. The results indicate that: (a) hepatocytes can divide without prior removal of the subsinusoidal extracellular matrix; (b) during regeneration, hepatocyte division precedes sinusoidal formation; (c) during hepatic regeneration, and in spite of the presence of laminin in Ito cells, no basement membranes are formed; (d) the prominent expression of laminin and its proposed functions in morphogenesis suggest a critical role for this matrix component in the formation and reorganization of the regenerating liver.  相似文献   

10.
 In order to analyse the regional and age-related variations of primate condyles, immunohistochemical techniques were used to examine the localization of types I, II and III collagen and a variety of glycosaminoglycans in distinct anteroposterior regions of the mandibular condyle of two growing female rhesus monkeys (Macaca mulatta). In the juvenile monkey staining for types I and III collagen was weak in the fibrous tissue layer, intense in the pre-cartilaginous tissue layer and faint in the cartilaginous tissue layer; staining was significantly more intense in the posterosuperior and posterior regions than in the anterior region. Similarly, staining for cartilage-characteristic extracellular matrices, including type II collagen and keratan sulfate, was intense in the cartilaginous tissue layer of the posterior condyle. In contrast, in the late-adolescent monkey staining for the extracellular matrices was more intense in the anterior half of the condyle (i.e. from the anterior to the posterosuperior region) than in the posterior region, and most intense in the posterosuperior region. The results demonstrate that marked regional differences exist in the phenotypic expression of the extracellular matrices in the mandibular condyles of growing monkeys and that these differences vary between different developmental stages. The variations probably reflect the predominance of competing growth and articulatory functions in the mandibular condyles. Accepted: 19 July 1996  相似文献   

11.
Decidualization in mice comprises a deep remodeling of extracellular matrix (ECM) components of the endometrium. In a previous biochemical study we showed that collagen types I and III are present in both pregnant and nonpregnant mouse endometrium, whereas collagen type V is expressed exclusively after the onset of decidualization. The distribution of collagen types in the pregnant mouse endometrium and possible changes of these molecular types in the different regions of the decidua is, however, not known. Using immunofluorescence and confocal microscopy we showed the presence of collagen types I, III, and V in the endometrial stroma of implantation and interimplantation sites from days 5 to 8 of pregnancy in the mouse. Collagen type III was chiefly expressed in the implantation sites and was the only collagen type to be present in the materno-fetal interface on the day of the embryo implantation. However, collagen type I was the predominant collagen in the interimplantation sites. Collagen type V was weakly expressed in the nondecidualized stroma during all periods but was expressed in larger amounts in the decidualized areas on day 7 of pregnancy, simultaneously with the accumulation of thick collagen fibrils in the same region. The highest immunofluorescence labeling for the three types of collagen was observed on day 7 when the antimesometrial decidual tissue achieved its greatest development. These data support previous studies that showed an intense ECM remodeling of the mouse endometrial stroma during the beginning of pregnancy. This outstanding remodeling may be important to stabilize placental anchorage.  相似文献   

12.
Extracellular matrix components have rarely been the focus of interest in juvenile angiofibroma (JA) studies. Although JAs are known to be collagen-rich tumours, single collagens have not been analysed so far. This investigation aimed to study the expression of the fibrillar collagen types I, II and III in JAs using quantitative RT-PCR (n = 15), Western blot analysis (n = 7) and immunohistochemical staining (n = 9). Nasal mucosa (NM) specimens were used as control tissues. ELISA investigation (n = 3) was performed to determine the concentration of C-terminal propeptide of type I collagen in blood serum before and after JA resection. Quantitative RT-PCR found significantly elevated Col1A1 (p < 0.001), Col1A2 (p < 0.001) and Col3A1 (p < 0.001) mRNA levels in JAs, compared with NM. Western blot analysis and immunohistochemical staining proved that there is a significant collagen type I and III protein expression in JAs. In none out of 3 patients, ELISA investigation found evidence for elevated concentrations of C-terminal propeptide of type I collagen before tumour resection, compared with postsurgical measurements. Results of the findings using quantitative RT-PCR, Western blot analysis and immunohistochemistry determined that type II collagen is practically absent in JAs. Based on these findings, type I and III collagen are confirmed as being major components of the extracellular matrix in JAs. However, our findings are not encouraging as regards the use of C-terminal Col I propeptide as a suitable serum tumour marker. Our findings confirming that collagen type II expression is practically absent in JAs refutes the theory that JAs originate in cartilage tissue.  相似文献   

13.
The main feature of the malignant schwannoma matrix studied by means of monospecific polyclonal antibodies and method of indirect immunofluorescence is the presence of focally distributed deposits of type IV collagen. Besides this, collagen of types I, III, V and fibronectin are also found. Qualitatively, the extracellular matrix of both benign and malignant schwannoma is similar. The focal localization of type IV collagen is probably associated with areas of the anaplastic lemmocytes proliferation. It is suggested to use the obtained data for the differential diagnosis of malignant schwannoma and fibrosarcoma.  相似文献   

14.
During tissue response to injury the glycoproteins fibronectin and Type III collagen are synthesized in increased amounts. We have studied the distribution of these molecules in the healing tendon at various times after injury by comparison with that of the major constituent of normal tendon, Type I collagen. Immunofluorescent localization demonstrated the presence of fibronectin throughout the tendon within one week after injury. Staining was found in the matrix, both around capillaries and around fibroblast-like cells. Fibronectin was still apparent in the healing tendon at one month after injury, but after a further two months was no longer detectable. Type III collagen was present both in pericellular and matrix locations until three months after injury, and matrix staining was apparent during the entire fourteen-month period under study. Type III collagen was also found throughout the matrix of the contralateral superficial flexor tendon during this period.  相似文献   

15.
 摘要: 目的 研究瘦素(Leptin)及I、 III型胶原蛋白及基因在肝纤维化模型组织中的动态表达水平。方法 四氯化碳(CCl4)皮下注射法制备肝纤维化模型,分别以Western blot及RT-PCR法检测Leptin及I、 III型胶原蛋白及基因在肝纤维化组织中的动态表达。结果 Leptin以及I、 III型胶原蛋白及基因在正常对照组肝脏中均有微量表达,CCl4注射2周后,三者的表达均开始增强,随着纤维化发展呈梯度增加。其mRNA表达水平在模型组明显高于正常组 (P<0.05);在肝纤维化过程中,Leptin与I型胶原(r=0.595,P=0.017)及Leptin与III型胶原(r=0.478,P=0.011) 的动态改变呈显著正相关。结论 Leptin的表达随着纤维化的程度加重而逐步增强,在肝纤维化过程中,Leptin可能参与了细胞外基质成分(ECM)的合成与降解。  相似文献   

16.
Uterine biopsies were collected at cycle days 1 (oestrous), 8, 15 and 19 in six cows. Unfixed cryostat sections were used to immunolocalise collagen types I, III, IV and VI by an indirect FITC method. Collagen I was sparsely found in the endometrium where it formed a fine meshwork of thin fibres directly below the surface epithelium, clearly visible only at cycle days 8 and 15. Collagen III formed the bulk of connective tissue fibres and was arranged in fine aggregates within the superficial endometrial stroma, while in the deeper areas it consisted of many thick fibre bundles. Collagen IV was found in basement membranes underlying all endometrial epithelia. Furthermore, it surrounded smooth muscle cells of blood vessels. A few single fibrils also stained positively within the endometrial stroma, more numerous at cycle days 1 and 19 as compared to days 8 and 15. Collagen VI formed a mesh of fine and pericellularly situated fibrils within the endometrial stroma. The contribution of the collagen types studied to the connective tissue of caruncles, blood vessels, lymph follicles, and myometrium is also reported. The results of the present study indicate that the connective tissue of the bovine uterine wall is composed of different collagen types, which exhibit a characteristic distribution pattern each. The day of cycle may influence amounts and organisation of collagen types I and IV as demonstrated here at the light-microscopical level.  相似文献   

17.
18.
Summary Twelve oral AIDS-associated Kaposi sarcomas (KS) were studied for the distribution of extracellular matrix components using indirect immunofluorescence. Staining for basement membrane (BM) components revealed two distinct patterns of distribution: a delicate and partly fragmented lining of BMs around sinusoid-like vascular spaces or an occasional diffuse interstitial fluorescence in the tumour stroma; or an irregular broad rim of fluorescence in walls of larger blood vessels. These findings support a vascular cell origin of the endothelial- and spindle cell component in KS. The tumour stroma was almost completely negative for collagen type V and undulin, whereas an intensive fluorescence was noted for procollagens type I, III and collagen type VI. In areas adjacent to KS a loss of procollagens type I and III, collagens type V, VI and undulin was noted. An intimal sheath of collagen type V was usually absent from blood vessels of the tumour or the peritumourous connective tissue. Immunohistochemical findings indicate that the preexisting interstitial connective tissue matrix is destroyed during tumour invasion and that subsequently procollagens type I, III and collagen type VI are synthesized de novo by cells of the tumour stroma.This study was supported by the Deutsche Forschungsgemeinschaft (Be 1017/1-2)  相似文献   

19.
《Acta biomaterialia》2014,10(6):2693-2702
Cell fate is known to be triggered by cues from the extracellular matrix, including its chemical, biological and physical characteristics. Specifically, mechanical and topological properties are increasingly recognized as important signals. The aim of this work was to provide an easily accessible biomimetic in vitro platform of topologically defined collagen I matrices to dissect cell behaviour under various conditions in vitro. We reconstituted covalently bound layers of three-dimensional (3-D) networks of collagen type I and collagen type V with a defined network topology. A new erosion algorithm enabled us to analyse the mean pore diameter and fibril content, while the mean fibril diameter was examined by an autocorrelation method. Different concentrations and ratios of collagen I and V resulted in pore diameters from 2.4 to 4.5 μm and fibril diameters from 0.6 to 0.8 μm. A comparison of telopeptide intact collagen I to telopeptide deficient collagen I revealed obvious differences in network structure. The good correlation of the topological data to measurements of network stiffness as well as invasion of human dermal fibroblasts proves that the topological analysis provides meaningful measures of the functional characteristics of the reconstituted 3-D collagen matrices.  相似文献   

20.
Peroxiredoxins (Prxs) are a recently characterized group of thiol-containing proteins with efficient antioxidant capacity, capable of consuming hydrogen peroxide in living cells. Altogether six distinct Prxs have been characterized in mammalian tissues. Their expression was investigated in histological samples of mesothelioma and in cell lines established from the tumours of mesothelioma patients. Four cases with histopathologically healthy pleura from non-smokers were used as controls. Healthy pleural mesothelium was negative or very weakly positive for all Prxs. In mesothelioma, the most prominent reactivity was observed with Prxs I, II, V, and VI. Prx I was highly or moderately expressed in 25/36 cases, the corresponding figures for Prxs II-VI being 27/36 (Prx II), 13/36 (Prx III), 2/36 (Prx IV), 24/36 (Prx V), and 30/36 (Prx VI). Positive staining was observed both in the cytosolic and the nuclear compartment, with the exception of Prx III, which showed no nuclear reactivity. The staining pattern of Prxs III and V was granular. Immunoelectron microscopic localization of Prxs was in accordance with the immunohistochemical findings, showing diffuse cytoplasmic localization for Prxs I, II, IV, and VI and distinct mitochondrial labelling for Prxs III and V. There was no significant association between the extent of staining and different Prxs. It appeared that Prxs may not have prognostic significance, but being prominently expressed in most mesotheliomas these proteins, at least in theory, may play a role in the primary drug resistance of this disease.  相似文献   

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