• Tuberculosis and Respiratory Diseases
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• v.58 no.3
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• pp.267-276
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• 2005

Background : The transforming growth $factor-{\beta}1$ ($TGF-{\beta}1$) plays a key role in lung fibrosis. However, the molecular mechanisms involved in $TGF-{\beta}1$-induced lung fibrosis are unclear. $TGF-{\beta}1$ is the key inducer of myofibroblast transdifferentiation via de novo synthesis of ${\alpha}-smooth$ muscle actin (${\alpha}-SMA$). Since $TGF-{\beta}1$ signals through reactive oxygen species (ROS) and ROS have been shown to induce accumulation of extracellular matrix (ECM) in various tissues, this study examined if ROS play a role in $TGF-{\beta}1$-induced fibronectin secretion and ${\alpha}-SMA$ expression in human lung fibroblasts, MRC-5 cells. Methods : Growth arrested and synchronized MRC-5 cells were stimulated with $TGF-{\beta}1$ (0.2-10 ng/ml) in the presence or absence of N-acetylcysteine (NAC) or diphenyleneiodonium (DPI) for up to 96 hours. Dichlorofluorescein (DCF)-sensitive cellular ROS were measured by FACScan and secreted fibronectin and cellular ${\alpha}-SMA$ by Western blot analysis. Results : $TGF-{\beta}1$ increased the level of fibronectin secretion and ${\alpha}-SMA$ expression in MRC-5 cells in a dosedependent manner. Both NAC (20 and 30 mM) and DPI (1 and $5{\mu}M$) significantly inhibited $TGF-{\beta}1$-induced fibronectin and ${\alpha}-SMA$ upregulation. The $TGF-{\beta}1$-induced cellular ROS level was also significantly reduced by NAC and DPI. Conclusions : The results suggest that NADPH oxidase-dependent ROS play an important role in $TGF-{\beta}1$-induced fibronectin secretion and ${\alpha}-SMA$ expression in MRC-5 cells, which leads to myofibroblast transdifferentiation and progressive lung fibrosis.

• Korean Journal of Veterinary Research
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• v.37 no.4
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• pp.875-882
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• 1997

To produce the recombinant fibronectin-binding protein(FnBP) for development of subunit vaccine against Staphylococcus aureus. The fnbp gene was amplified from the chromosomal DNA of S aureus KNU 196 strain using the polymerase chain reaction, and cloned into pGEX-4T-2. Then, the recombinant FnBP fused with glutathione-S-transferase was produced in E coli, purified by affinity chromatography, and identified its antigenicity and immunogenicity by Western blot. The recombinant FnBP produced in this study is considered to have the same property of native FnBP purified from S aureus, and is expected to be useful as a candidate for S aureus subunit vaccine.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.30-33
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• 2002

We have shown that it is possible to form a fibrilar network of fibronectin on a polyelectrolyte polymer film whose dimensions are similar to those reported on the extra cellular matrix. The fibronectin network was observed to form only when the charge density of the polymer was in excess of the natural charge density of the cell wall. Furthermore, the self-organized fibronectin layer was much thicker than the polymer film, indicating that long ranged interaction may playa key role in the assembly process. It is therefore important to understand the structure of the polymer layer/protein interface. Here we report on a neutron reflectivity study where we explore the structure of the polyelectrolyte layer, in this case sulfonated polystyrene (PSSx,), with varying degree of sulfonation (x<30%), as a function of sulfur content and counter ion concentration. These results are then correlated with systemic study of the adsorption and the multilayer formation of fibronectin as a function of incubation time for various sulfonation levels of $PSSx.^1$

• The Korean Journal of Zoology
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• v.37 no.4
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• pp.592-596
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• 1994

The interaction between fibronectin (FN) and its receptors controls cell attachment and migration, two crucial events during monocyte development and differentiation. To investigate the functional role of FN and its receptor, we have studied adhesion of monocyte to two different regions of FN (38- and 85-kDa domain), as well as the expression of the integrin during monocle differentiation. Anti-integrin Rl subunit antibody completely blocked the attachment of FN-coated latex beads to macrophage, but the effect of anti-integrin u4 antibody was much less significant. Rat monocyte expressed integrin $u4\beta1$ predominantly, while macrophage expressed $\alpha5\beta1$ as analyzed tv flow cvtometer and western blot. From these results, it can be suggested that these two integrins plan different roles during monocyte differentiation.

• 대한치과보철학회:학술대회논문집
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• 2005.11a
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• pp.92-92
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• 2005

• Journal of Periodontal and Implant Science
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• v.42 no.3
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• pp.95-104
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• 2012

Purpose: The purpose of this study was to determine whether increasing the Ti6Al4V surface oxide negative charge through heat ($600^{\circ}C$) or radiofrequency plasma glow discharge (RFGD) pretreatment, with or without a subsequent coating with fibronectin, stimulated osteoblast gene marker expression in the MC3T3 osteoprogenitor cell line. Methods: Quantitative real-time polymerase chain reaction was used to measure changes over time in the mRNA levels for osteoblast gene markers, including alkaline phosphatase, bone sialoprotein, collagen type I (${\alpha}1$), osteocalcin, osteopontin and parathyroid hormone-related peptide (PTH-rP), and the osteoblast precursor genes Runx2 and osterix. Results: Osteoprogenitors began to differentiate earlier on disks that were pretreated with heat or RFGD. The pretreatments increased gene marker expression in the absence of a fibronectin coating. However, pretreatments increased osteoblast gene expression for fibronectin-coated disks more than uncoated disks, suggesting a surface oxide-mediated specific enhancement of fibronectin's bioactivity. Heat pretreatment had greater effects on the mRNA expression of genes for PTH-rP, alkaline phosphatase and osteocalcin while RFGD pretreatment had greater effects on osteopontin and bone sialoprotein gene expression. Conclusions: The results suggest that heat and RFGD pretreatments of the Ti6Al4V surface oxide stimulated osteoblast differentiation through an enhancement of (a) coated fibronectin's bioactivity and (b) the bioactivities of other serum or matrix proteins. The quantitative differences in the effects of the two pretreatments on osteoblast gene marker expression may have arisen from the unique physico-chemical characteristics of each resultant oxide surface. Therefore, engineering the Ti6Al4V surface oxide to become more negatively charged can be used to accelerate osteoblast differentiation through fibronectin-dependent and independent mechanisms.

• Journal of Periodontal and Implant Science
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• v.41 no.5
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• pp.242-247
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• 2011

Purpose: The purpose of this study was to characterize the osseointegration of the fibronectin-coated implant surface. Methods: Sand-blasted, large-grit, acid-etched (SLA) surface implants, with or without a thin calcium phosphate and fibronectin coating, were placed in edentulous mandibles of dogs 8 weeks after extraction. All dogs were sacrificed forhistological and histomorphometric evaluation after 4- and 8-week healing periods. Results: All types of implants were clinically stable without any mobility. Although the bone-to-implant contact and bone density of the SLA implants coated with calcium phosphate (CaP)/fibronectin were lower than the uncoated SLA implants, there were no significant differences between the uncoated SLA surface group and the SLA surface coated with CaP/fibronectin group. Conclusions: Within the limits of this study, SLA surfaces coated with CaP/fibronectin were shown to have comparable bone-to-implant contact and bone density to uncoated SLA surfaces.

• Journal of Periodontal and Implant Science
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• v.25 no.2
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• pp.253-266
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• 1995

Recently, available interests concerning the biologic significance of the extracellular matrix and proliferating cells associated with periodontal disease has been increased. The distribution or expression of cellular proliferation by PCNA, macrophage detection by ${\alpha}$-l-antichymotrypsin, fibronectin playing a important role in host defence mechanisms indirectly, and transglutaminase that cross linked to fibronectin and stimulate fibrin stabilization were studied in inflammed and healthy gingiva. The excised tissue samples were fixed neutral formalin for 24 hours, embedded with paraffin, sectioned at 4-61lffi in thickness, and immunohistochemically processed by LSAB method. The positive reaction to PCNA was localized in the suprabasal and basal layer of inflammed gingiva and an increasing reactivity was observed than healthy gingiva. ${\alpha}$-I-antichymotrypsin positive cells were localized in the basal layer of inflammed gingiva, and there was no or rare positive cells in healthy gingiva. The positive reaction to fibronectin in inflammed gingiva was more than healthy gingiva,"and shown in the connective tissue subjacent to basement membrane of epithelium and in the periphery of the collagen fiber bundles. The positive cells by transglutaminase in inflammed gingiva were noted in suprabasal, spinous, and keratin layer of epithelium, and slightly increased in the capillaries of connective tissues. But the results of this study demonstrated in vitro reaction. Therefore, the role of PCNA,${\alpha}$-l-antichyrnotrypsin, transglutaminase, fibronectin and coefficient with other growth factor and extracellular matrix were further investigated in vivo.

• Korean Journal of Head & Neck Oncology
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• v.13 no.2
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• pp.180-186
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• 1997

Objectives: Salivary gland tumors pose considerable difficulty in diagnostic and prognostic assessment based on the histopathologic features alone. We studied the expression of type IV collagen and fibronectin in salivary gland tumors with special emphasis on the differential diagnostic significance. Materials and Methods: We did immunohistochemical stain on paraffin embedded tissues of 33 benign and 24 malignant salivary gland tumors using monoclonal antibody for type IV collagen and polyclonal antibody for fibronectin. Results: 1) Well preserved linear basement membrane-like staining of type IV collagen was detected in duct-cell-derived benign salivary gland tumors. But pleomorphic adenoma exhibited a heterogeneous pattern as focal augmentation and interruption. 2) In malignant tumors, type IV collagen was distributed in an irregular, interrupted manner or completely absent. Adenoid cystic carcinomas displayed a marked staining of the basal membrane associated substances in the pseudocysts. 3) The staining pattern of fibronectin was similar to that of type IV collagen execpt more dense in the stroma. 4) Salivary gland tumors which have a prominent myoepithelial cell component revealed a particular deposition of basement membrane materials adjacent to the myoepithelial cells. Conclusion: The study of the basal membrane substances may be helpful for differential diagnosis of benign and malignant salivary gland tumors and identifying special features of salivary gland tumors such as pseudocystic pattern of adenoid cystic carcinoma. Also we think that the myoepithelial cells contribute to the formation of basement membrane materials.

• The korean journal of orthodontics
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• v.23 no.2 s.41
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• pp.229-248
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• 1993

[ $Interferon-\gamma$ ] has been suggested as a cytokine of connective tissue stabilizer. In addition, it has also been demonstrated that this cytokine inhibited bone remodeling activities of the bone derived cells. In order to illuminate the effects of this cytokine in orthodontic force induced bone remodeling, it was administered to primary cultured periodontal ligament cells which have been known to have some osteoblast like characteristics. $Interferon-\gamma$ slightly decreased $[^3H]thymidine$ incorporation rate without a significant change in the total cellular DNA content up to 1000 U/ml, which meant these doses were not cytotoxic to the cell. Total protein synthesis was not influenced by various concentration of interferon-y whether it was determined by the $[^3H]proline$ incorporation rate or by the Lowry smethod. The effect of $interferon-\gamma$ on the individual protein was, however, differential, ie, it increased $[^3H]proline$ incorporation into the noncollagenous protein marginally, while it decreased $[^3H]proline$ incorporation into the collagen, so that it caused dose-dependent suppression of the relative collagen synthesis. On the contrary, the fibronectin synthesis determined by the ELISA was increased by 1000 U/ml of $interferon-\gamma$. The differential effects of the interferon-y on the collagen and fibronectin synthesis exhibited not only their protein level but also the steady state mRNA level. $Interferon-\gamma$ decreased steady state level of ${\alpha}1(I)$ procollagen mRNA significantly, while showing no significant changes in the fibronectin mRNA level. In addition to this, it was also found that indomethacin did not affect on the $interferon-\gamma$ induced collagen decrease in this cell, which meant prostaglandins were not involed in the process of $interferon-\gamma$ induced collagen decrease. So it can be concluded that the incubation of periodontal ligament cells with 1000 U/ml of $interferon-\gamma$ for 24 hr showed differential effects on the type I collagen and fibronectin gene expression. The decrease in relative collagen synthesis in the protein level was related with decrease in the steady state level of mRNA, while the increase in the fibronectin synthesis in the protein level was not correlated with the mRNA level.