• The Korean Journal of Zoology
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• v.38 no.4
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• pp.457-464
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• 1995

Hela cells, a transformed human epithelial cell line, attach to various substrata but subsequent spreading is specific to collagen or gelatin. The spreading is initiated by the activation of phospholipase $A_2$ (PLA$_2$) which produces arachidonic acid (AA) as a consequence of cell surface collagen receptor clustering. This study examines the mechanism of PLA$_2$activation and which phospholipids are hydrolyzed by PIA$_2$ to release AA in response to Hela cell adhesion to a gelatin substratum. The levels of phosphatidyicholine decreases, among various phospholipids, during attachment and spreading of Hela cells. Lysophosphatidyicholine Is the only lysophospholipids formed during ileLa cell adhesion indicating that clustered collagen receptors activate PLA$_2$to hydrolyze posphatidylcholine to AA and lysophosphatidylcholine. Among various molecular entitles which are known to regulate PLA$_2$ activation, we have previously shown that PLA2 activation is not mediated by either changes in $Ca_2$+ levels, alkalinization of cytoplasmic p11, or activation of protein hinase C. It is also likely that PIA2 activation is not mediated by either pertussis or cholera toxinsensitive G proteins as those toxins do not affect both AA release and cell spreading.

• Journal of Biomedical Engineering Research
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• v.10 no.2
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• pp.195-202
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• 1989

Chinese Hamster Ovary( CHO) cells were cultured on the surface-modified polymers described in the previous study( "Polymer Surfaces for Cell Adhesion. 1. Surface Modification of Polymers and ESCA Analysis, " J. of KOSOMBE, Vol. 10, No. 1, 43-51, 1989). Among the physicochemical treatment methods. the chloric acid treatment was found to be the best method of rendering the polymer surfaces adhesive for CHO cells probably due to the high density of hydroxyl groups on the surface. Among the biological methods, the fibronectin treatment was best for CHO cell-compatibility probably due to specific active sites existed on the tell-binding domains of the fibronectin structure. When we compare the cell-compatibility of the chloric acid - and the fibronectin -treated PET surfaces, the number of cells attached on the surfaces were increased by 460.5 % and 559.0 % and, respectively, after 32 hr CHO cell culture, compared to that of untreated PET.eated PET.

• Bulletin of the Korean Chemical Society
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• v.30 no.8
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• pp.1817-1820
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• 2009

Controlling cell-matrix interactions is critical in regulating cell phenotypes for tissue engineering applications. Cellular adhesion to synthetic extracellular matrices (ECMs) can be enhanced by introduction of adhesion ligands to the matrices. We tested the hypothesis that biophysical cues such as ligand organization in synthetic ECMs play an important role in modulating cell responses to the microenvironment. To investigate and monitor cell-matrix interactions, we used a fluorescence resonance energy transfer (FRET) technique with cell-interactive polymers generated by conjugating a peptide with the sequence of arginine-glycine-aspartic acid (RGD) to alginate hydrogels.

• The Journal of Korean Society of Virology
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• v.26 no.1
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• pp.47-58
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• 1996

Histopathological vascular changes in hemorrhagic fever with renal syndrome (HFRS) caused by Hantaan virus include increased vascular permeability, disseminated intravascular coagulation, thrombocytopenia and changes in coagulation activity. Although vascular endothelial cells of main target organs such as kidney infected with Hantaan virus are not damaged but swelling of endothelial cells, perivascular exudates and infiltration of mononuclear cells and fresh interstitial hemorrhages are common. However, the pathogenesis of cell infiltration and hemorrhages around vascular endothelial cells are not well understood. Some endothelial cell molecules or vascular adhesins that acts as adhesion moleulces for leukocyte are expressed on endothelial cells close to site of inflammation. However, whether the expression of endothelial adhesion molecules such as vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule (ICAM-1) and endothelial leukocyte adhesion molecule (ELAM) on vascular endothelial cells are increased by infection with Hantaan virus has not been studied. In this study, the relationship between the expression of VCAM-1, ICAM-1 and ELAM and adhesion of mononuclear cells on endothelial cells of human blood vessels infected with Hantaan virus was investigated. The endothelial cells of umbilical vein was passaged three times in culture medium and the monolayered cells were infected with $10^5\;pfu/ml$ of Hantaan virus grown in Vera E6 cell cultures. The multiplication of virus in cultured endothelial cells was monitored by immunohistochemistry and the expression of adhesion molecules was demonstrated by immunohistochemistry using monoclonal antibodies against VCAM-1, ICAM-1 and ELAM. And in situ hybriditation against ICAM-1 was also performed. The endothelial adhesion molecules, VCAM and ICAM, were expressed after 6 hours postinfection, respectively, and their expressions lasted for 72 hours. Similar expression of VCAM and ICAM appeared on endothelial cells by infection with virus, but the expression of ELAM was not recognized up to 72 hours postinfection. Microscopically, it was noted that many monocuclear cells adhered on endothelial cells infected with viruses. In an electronmicroscopic study, the transendothelial migration of mononuclear cells was observed on monolayered endothelial cells infected with virus. This results suggested that the endothelial adhesion molecules, particulary VCAM and ICAM, might be expressed on endothelial cells by infection with Hantaan virus and these molecules play a key role in the adhesion and extravasation of inflammatory cells around blood vessels.

• Proceedings of the PSK Conference
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• 2003.10a
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• pp.100-101
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• 2003

Cell-cell and cell-matrix interaction is clearly required for metazoans not only to hold their cells together but also to conduct more sophisticated biological processes. Each cell has adhesion molecules on its cell membrane to link extracellular matrix and adjacent cells to the intracellular cytoskeleton, and also to transduce signals. In complex metazoans, information is transmitted from one cell to another by mechanisms such as direct intercellular communication, soluble signal molecules among distant cells, and local cellular environments formed by highly specialized extracellular matrix. (omitted)

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1215-1220
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• 2004

Cell adhesion to any material surface is considered to be fundamental and important phenomenon in the fields of tissue engineering. Cell adhesion molecules, mechanism, and attachment force have been studied and described a lot. However, the effects of mechanical stimuli on the adhesive forces still have been left much to be investigated. In this study, to investigate the changes in cell adhesive force due to resting time period during the intermittent hydrostatic pressurizing (IHP), cells were cultured under the IHP with various resting times. Then the cell adhesive forces were measured quantitatively utilizing a cell detachment test system and immunofluorescent staining was performed using fluorescent microscopy. In the results, immediately after mechanical stimuli (150 minutes after seeding) and one hour later (210 minutes after seeding), the average adhesive force of experimental group 5 (resting time: 15min) compared with that of control group at same culture time was increased significantly (p<0.05). The results indicated that IHP can contribute in improving cell adhesive force and some of time intervals were required for the expression of cell response.

• Journal of the Korean institute of surface engineering
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• v.42 no.5
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• pp.203-207
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• 2009

Interaction between human osteoblast (hFOB 1.19) and CrN films was conducted in vitro. CrN films were produced by cathodic arc plasma deposition. The surface was characterized by atomic force microscopy (AFM). CrN films, glass substrates and TiN films were cultured with human osteoblasts for 48 and 72 hours. Actin stress fiber patterns and cell adhesion of osteoblasts were found less organized and weak on CrN films compared to those on the glass substrates and the TiN films. Human osteoblasts also showed less proliferation and less distributed microtubule on CrN films compared to those on glass substrates and TiN films. Focal contact adhesion was not observed in the cells cultured on CrN films, whereas focal contact adhesion was observed well in the cells cultured on glass substrates and TiN films. As a result, the CrN film is a potential candidate as a surface coating to be used for implantable devices which requires minimal cellular adhesion.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.5
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• pp.635-641
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• 2011

Anti-atherogenic effects in tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$)-stimulated human umbilical vein endothelial cells (HUVEC) are involved with suppressed oxidative stress, cell adhesion molecules, and pro-inflammatory factors. The aim of this study was to determine whether green tea seed coat ethyl acetate fraction (GTSCE) could modulate cell adhesion molecules and inflammatory mediators in HUVEC stimulated with TNF-${\alpha}$. Nitric oxide (NO) production was significantly increased in TNF-${\alpha}$-stimulated HUVEC compared to TNF-${\alpha}$ only treated cells. The NO that is produced by endothelial nitric oxide synthase dilates blood vessels and has protective effects against platelet and leucocyte adhesion. GTSCE at 25, 50, 75, and $100\;{\mu}g$/mL significantly (p<0.05) reduced TNF-${\alpha}$ production. GTSCE significantly (p<0.05) inhibited soluble vascular cell adhesion molecule-1 level, in a dose-dependent manner. Monocyte chemoattractant protein-1 level was also significantly (p<0.05) inhibited by GTSCE treatment at $75\;{\mu}g$/mL compared to the TNF-${\alpha}$-only treated group. Total antioxidant capacity by GTSCE was significantly (p<0.05) enhanced compared to the TNF-${\alpha}$-only treated group. These results suggest that GTSCE can inhibit the production of cell adhesion molecules and inflammatory mediators and could be used as a candidate bioactive material to prevent the development of atherosclerosis.

• Animal cells and systems
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• v.13 no.2
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• pp.113-118
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• 2009

Extracts derived from various medical mushrooms have been reported to have antitumor and immuno-modulatory properties. In order to investigate the antitumor activity of keumsa Linteusan, the water extract of Phellinus Iimteus, HT1080 cells, a human fibrosarcoma cell line, were treated with it and changes in cellular migration potential was tested in vitro. At a concentration range below 1,000 $\mu$g/mL, Linteusan blocked, in a dose dependent manner, the migration of cells through Matrigel as well as Boyden chamber without affecting the viability of the cells. Prolonged treatment of HT1080 cells with Linteusan suppressed TNFa induced production of matrix metalloproteinase (MMP)-9 as well as basal level expression of MMP-2. Linteusan also affected the adhesion of the cells to fibronectin-coated surfaces. The effect of Linteusan on cell signaling pathways was also tested. Linteusan specifically affected TNF-$\alpha$ induced phosphorylation of AKT in a dose-dependent manner, while phosphorylation levels of ERK remained unaffected. These data indicate that Linteusan blocks the migration of HT1080 cells by affecting various processes associated with cell migration such as the expression of matrix degradingenzymes,cell adhesion, and AKT-medicated cellular signaling pathways.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.78-81
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• 2008

We developed tight adhesion techniques of two plastic substrates to maintain cell gap stability for rugged flexible LCDs. By combining rigid spacers and several adhesion materials, we demonstrated mechanically very stable flexible LCDs against pressure and bending.