• Parasites, Hosts and Diseases
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• v.51 no.1
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• pp.61-68
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• 2013

Entamoeba histolytica, which causes amoebic colitis and occasionally liver abscess in humans, is able to induce host cell death. However, signaling mechanisms of colon cell death induced by E. histolytica are not fully elucidated. In this study, we investigated the signaling role of NOX in cell death of HT29 colonic epithelial cells induced by E. histolytica. Incubation of HT29 cells with amoebic trophozoites resulted in DNA fragmentation that is a hallmark of apoptotic cell death. In addition, E. histolytica generate intracellular reactive oxygen species (ROS) in a contact-dependent manner. Inhibition of intracellular ROS level with treatment with DPI, an inhibitor of NADPH oxidases (NOXs), decreased Entamoebainduced ROS generation and cell death in HT29 cells. However, pan-caspase inhibitor did not affect E. histolytica-induced HT29 cell death. In HT29 cells, catalytic subunit NOX1 and regulatory subunit Rac1 for NOX1 activation were highly expressed. We next investigated whether NADPH oxidase 1 (NOX1)-derived ROS is closely associated with HT29 cell death induced by E. histolytica. Suppression of Rac1 by siRNA significantly inhibited Entamoeba-induced cell death. Moreover, knockdown of NOX1 by siRNA, effectively inhibited E. histolytica-triggered DNA fragmentation in HT29 cells. These results suggest that NOX1-derived ROS is required for apoptotic cell death in HT29 colon epithelial cells induced by E. histolytica.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.33 no.5
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• pp.437-444
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• 2007

Vinyl acetate has been widely used for the manufacture of polyvinyl alcohol emulsion, which is primary ingredient of adhesive, paints, textile, paperboard coatings, etc. Since these products are plentiful and frequently used around us, workers and consumers are at health risk. International Agency for Research on Cancer(IARC) classified vinyl acetate as group 2B(possibly carcinogenic to humans). Among the organs targeted, the oral cavity is the most vulnerable organ affected by the carcinogenic effects of vinyl acetate. Since the origin of most of oral cancer is derived from the epithelial cells, it is important to understand the carcinogenic potential of vinyl acetate in human epithelial cells. Thus, the present study has attempted to utilize the immortalized human epithelial cell model to assess the carcinogenic potency of this chemical and to understand the underlying mechanisms.

• Journal of Embryo Transfer
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• v.11 no.3
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• pp.201-210
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• 1996

This experiment was carried out to evaluate the effect of early mouse embryonic development in vitro by co-culture with bovine and porcine oviductal epithelial cells (BOEC and POEC). The 2-cell embryos were collected from the oviducts of the superovulated and mated cultured in D-PBS /15% FCS at 48 hours after hCG injection. The in vitro developmental rate of blastocyst formation in the embryos were examined under the fllowing treatments; 1) TCM 199 added 15% HCS, 2) Ham's F-10 added 15% HCS, 3) MediCult IVF medium, 4) TCM 199 added 15% HCS + BOEC, 5) TCM 199 added 15% HCS + POEC, 6) Ham's F40 added 15% HCS + BOEC, 7) Ham's F-10 added 15% HCS + POEC,8) MediCult IVF medium + BOEC, 9) MediCult IVF medium + POEC. For a comparative study of in vitro development for 96 hours after hCG injection, were cultured with oviductal epithelial cell and media only. The obtained results were 2-cell embryos developed to the blastocyst stage in TCM 199, Ham's F-10 and MediCult IVF medium at the rates of 84.4,83.2 and 81.6%. respectively. The higher developmental rates(91~97%) of blastocyst formation was appeared when the embryos were co-cultured with a monolayer of bovine or porcine oviductal epithelial cells in TCM 199 or Ham's F-10 and MediCult IVF media. No significant difference in developmental rates was shown between bovine and porcine oviductal epithelial cells but significant difference in co-culture system in comparison between media only system and co-cultures. In conclusions, oviductal epithelial cells, BOEC and POEC, when co-culture with mouse early embryos improved the rates of development, blastocyst and hatching. Therefore, it is suggested that co-culture system using oviductal epithelial cells improve early embryonic developtnent in mouse.

• Korean Journal of Veterinary Research
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• v.43 no.4
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• pp.649-656
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• 2003

We have a cultured method to grow rat mammary epithelial cells (RMEC) for 1 to 14 days in 1:1 mixture of Dulbecco's Modified Eagle Medium: Nutrient and F-12 (DMEM/F-12) containing 10% fetal bovine serum (FBS), human EGF, insulin, hydrocortisone, human transferrin and $17{\beta}$-estradiol in vitro. We were able to isolate and distinguish two cell types, luminal epithelial cells and myoepithelial cells, from primary clutures of RMEC. Immunocytochemical stains were used to distingusih luminal epithelial cells and myoepithelial cells. Peanut lectin (PNA) was stained in most alveolar epithelail cells and luminal epithelial cells of rats, while Thy-1.1, a maker of potential rat mammary myoepithelial cells, was expressed in myoepithelial cells in the rat. Also, we examined the expression patterns of three types of gap junction proteins, connexin 26 ($C{\times}26$), connexins 32 ($C{\times}32$) and connexin 43 ($C{\times}43$) by immunocytochemistry and western blot analysis. In the cell types, the results show that at the early stage of culture, luminal epithelial cells were increased and these cells were surrounded by myoepithelial cells. At the late stage of culture, luminal epithelial cells were decreased, in contrast myoepithelial cells were increased. In the expression pattern of gap junction, $C{\times}26$ maintained it's expression until day 3, but afterwards gradually decreased in intensity. Expression of $C{\times}32$ remained until day 5, then decreased slightly. $C{\times}43$ gradually increased untill the middle time of culture then decreased in intensity. These results suggest that connexins may be important for the control of growth in rat mammary epithelial cell types.

• Clinical and Experimental Reproductive Medicine
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• v.45 no.1
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• pp.1-9
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• 2018

Objective: To determine the localization, expression, and function of Toll-like receptors (TLRs) in fallopian tube epithelial cells. Methods: The localization of TLRs in fallopian tube epithelial cells was investigated by immunostaining. Surprisingly, the intensity of staining was not equal in the secretory and ciliated cells. After primary cell culture of fallopian tube epithelial cells, ring cloning was used to isolate colonies of ciliated epithelial cells, distinct from non-ciliated epithelial cells. The expression of TLRs 1-10 was examined by quantitative real-time polymerase chain reaction, and protein localization was confirmed by immunostaining. The function of the TLRs was determined by interleukin (IL)-6 and IL-8 production in response to TLR2, TLR3, TLR5, TLR7, and TLR9 ligands. Results: Fallopian tube epithelial cells expressed TLRs 1-10 in a cell-type-specific manner. Exposing fallopian tube epithelial cells to TLR2, TLR3, TLR5, TLR7, and TLR9 agonists induced the secretion of proinflammatory cytokines such as IL-6 and IL-8. Conclusion: Our findings suggest that TLR expression in the fallopian tubes is cell-type-specific. According to our results, ciliated cells may play more effective role than non-ciliated cells in the innate immune defense of the fallopian tubes, and in interactions with gametes and embryos.

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.5
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• pp.303-310
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• 2002

Cell therapy applied to wound healing or tissue regeneration presents a revolutionary realm to which principles of gene engineering and delivery may be applied. One promising application is the transplantation of cells into the wounded tissue to help the tissue repair. However, when cells are transplanted from in vitro to in vivo, immune rejection occurs due to the immune response triggered by the activation of T-cell, and the transplanted cells are destroyed by the attack of activated T-cell and lose their function. Immune suppressant such as FK506 is commonly used to suppress immune rejection during transplantation. However, such kind of immune suppressants not only suppresses immune rejection in the periphery of transplanted cells but also suppresses whole immune response system against pathogenic infection. In order to solve this problem, we developed a method to protect the desired cells from immune rejection without impairing whole immune system during cell transplantation. Previously, we reported the success of constructing glomerular epithelial cells for removal of immune complex, in which complement receptor of type 1 (CR1) was over-expressed on the membrane of renal glomerular epithelial cells and could bind immune complex of DNA/anti-DNA-antibody to remove immune complex through phagocy-tosis [1]. Attempting to apply the CR1-expressing cells to cell therapy and evade immune rejection during cell transplantation, we constructed three plasmids containing genes encoding a soluble fusion protein of cytolytic T lymphocyte associated antigen-4 (CTLA4Ig) and an enhanced green fluorescent protein (EGFP). The plasmids were transfected to the above-mentioned glomerular epithelial cells to express both genes simultaneously. Using the clone cells for cell transplantation showed that mice with autoimmune disease prolonged their life significantly as compared with the control mice, and two injections of the cells at the beginning of two weeks resulted in remarkable survivability, whereas it requires half a year and 50 administrations of proteins purified from the same amount of cells to achieve the same effect.

• Journal of Microbiology and Biotechnology
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• v.27 no.4
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• pp.694-700
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• 2017

Clostridium difficile, which causes pseudomembranous colitis, releases toxin A and toxin B. These toxins are considered to be the main causative agents for the disease pathogenesis, and their expression is associated with a marked increase of apoptosis in mucosal epithelial cells. Colonic epithelial cells are believed to form a physical barrier between the lumen and the submucosa, and abnormally increased mucosal epithelial cell apoptosis is considered to be an initial step in gut inflammation responses. Therefore, one approach to treating pseudomembranous colitis would be to develop agents that block the mucosal epithelial cell apoptosis caused by toxin A, thus restoring barrier function and curing inflammatory responses in the gut. We recently isolated an antimicrobial peptide, Periplanetasin-2 (Peri-2, YPCKLNLKLGKVPFH) from the American cockroach, whose extracts have shown great potential for clinical use. Here, we assessed whether Peri-2 could inhibit the cell toxicity and inflammation caused by C. difficile toxin A. Indeed, in human colonocyte HT29 cells, Peri-2 inhibited the toxin A-induced decrease in cell proliferation and ameliorated the cell apoptosis induced by this toxin. Moreover, in the toxin A-induced mouse enteritis model, Peri-2 blocked the mucosal disruption and inflammatory response caused by toxin A. These results suggest that the American cockroach peptide Peri-2 could be a possible drug candidate for addressing the pseudomembranous colitis caused by C. difficile toxin A.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.8
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• pp.1100-1105
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• 2006

During involution of the mammary gland after the lactation period, the gland undergoes an extensive epithelial cell death. In our previous study, overexpression of an extracellular proteinase inhibitor (Expi) gene accelerated apoptosis of mammary epithelial cells. Here we found that expression of the cathepsin D gene was induced in the Expi-overexpressed apoptotic cells. To understand the role of cathepsin D in apoptosis, we transfected cathepsin D gene into mammary epithelial HC11 cells and established the stable cell lines overexpressing the cathepsin D gene. We found that overexpression of the cathepsin D gene partially induced apoptosis of mammary epithelial cells. Expression patterns of the cathepsin D gene were examined in mouse mammary gland at various reproductive stages. Expression of the cathepsin D gene was increased during involution stages compared to lactation stages, and highest expression levels were shown at involution on day 4. We also examined expression of the cathepsin D gene in various mouse tissues. Mammary gland at involution on day 2 showed highest levels of cathepsin D mRNA of the mouse tissues that we examined. Liver tissues showed high levels of cathepsin D expression. These results demonstrate that cathepsin D may contribute to the apoptotic process of mammary epithelial cells.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.16 no.3
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• pp.82-95
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• 2003

Chemokines are important for the recruitment of leukocytes to sites of infection, which is essential in host defense. The thymus and activation-regulated chemokine (TARC) is a CC chemokine which potentially plays a role via a paracrine mechanism in the development of allergic respiratory diseases. Objectives : The objective of this study is to investigate the effect of Youn-Gyo-Pae-Doc-San on the secretion of TARC of human bronchial epithelial cell Methods : Enzyme-linked immunosorbent assay (ELISA) was performed to detect the secretion of TARC. The cytotoxicity was measured by MTT assay. Results : Youn-Gyo-Pae-Doc-San significantly inhibited the secretion of TARC with a dose -dependant manner. The effective dosage did not have the cytotoxicity on human bronchial epithelial cell. Conclusions : Results of our study show that Youn-Gyo-Pae-Doc-San would play an important role in modulation of TARC in human bronchial epithelial cells.

• Korean Journal of Acupuncture
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• v.22 no.1
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• pp.23-32
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• 2005

Chemokines are important for the recruitment of leukocytes, which is essential in host defense to the sites of infection. The thymus and activation-regulated chemokine (TARC) is a CC chemokine which potentially plays a role via a paracrine mechanism in the development of allergic respiratory diseases. Objectives : The objective of this study is to investigate the effect of Ephedrae Herba Herbal Acupuncture Solution(EHS) on the secretion of TARC of human bronchial epithelial cell. Methods : Enzyme-linked immunosorbent assay (ELISA) was performed to detect the secretion of TARC. The cytotoxicity was measured by MTT assay. Results : EHS significantly inhibited the secretion of TARC with a dose-dependant manner. The effective dosage did not have the cytotoxicity on human bronchial epithelial cell. Conclusion : Results of our study imply that EHS would play an important role in modulation of TARC in human bronchial epithelial cells by MTT assay.