• Journal of Plant Biotechnology
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• 제37권3호
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• pp.283-291
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• 2010

Vaccine is one of the best known and most successful applications of immunological theory to human health and it protects human life through inducing the immune response in systemic compartment. However, when we consider the fact that mucosal epithelium is exposed to diverse foreign materials including viruses, bacteria, and food antigens and protects body from entry of unwanted materials using layer of tightly joined epithelial cells, establishing the immunological barrier on the lining of mucosal surfaces is believed to be an effective strategy to protect body from unwanted antigens. Unfortunately, however, oral mucosal site, which is considered as the best target to induce mucosal immune response due to application convenience, is prone to induce immune tolerance rather than immune stimulation. Since intestinal epithelium is tightly organized, a prerequisite for successful mucosal vaccination is delivery of antigen to mucosal immune induction site including a complex system of highly specialized cells such as M cells. Consequently, development of efficient mucosal adjuvant capable of introducing antigens to mucosal immune induction site and overcome oral tolerance is an important subject in oral vaccine development. In this review, various approaches on the development of oral mucosal adjuvants being suggested for effective oral mucosal immune induction.

• Parasites, Hosts and Diseases
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• 제31권2호
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• pp.83-90
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• 1993

간흡충에 감염된 담관은 확장되면서 상피세포의 수가 크게 증식하여 점막층이 두꺼워지고 과식증에 의해 점막의 단면이 유두상으로 관찰된다. Bromodeoxyuridine (BrdU)이 세포가 핵산을 복제할 때에 끼어 들어가는 성질을 이용하여, 이 연구에서는 담관 상피세포 중에서 합성기(Sphase)에 있는 세포의 분율을 파악하고자 하였다. 흰쥐에 간흡충의 피낭유충을 100 개씩 경구 감염시키고, 15주까지 간의 각 엽에 있는 담관의 조직절편을 만들어서 다세포군항체와 ABC complex를 이용한 염색을 실시하였다. 그 결과 충제가 들어 있는 담관에서는 감염 1주에 상피 세포의 2.9-10.2%가 염색에 양성이었고, 2주에 7.3-12.8%가, 5주에는 7.3-13.4%가, 15주에 8.4-14.8%가 BrdU를 함유하였다. 대조군 흰쥐나 실험군 동물의 감염되지 않은 담관의 경우에는 0-2.7%가 염색에 양성으로 나타났다. 염색된 상피세포는 주로 점막 상피세포층의 기저부에서 관찰되었다. 이 결과에 의하면 간흡충과 직접 접촉하는 담관의 상피세포가 뚜렷하게 증식하고 있어 충체의 어떠한 물리적인 또는 화학적인 자극이 있더라도 가까운 부위에서 주로 작용하고 있다고 판단하였다.

• 한국동물학회지
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• 제38권3호
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• pp.388-394
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• 1995

동면동물인 다람쥐를 활동기와 동면기로 나누어 소장 점막 상피세포인 원주세포와 점액세포의 미세구조 변화를 투과전자현미경을 이용하여 관찰하였다. 활동기의 원주세포에서는 많은수의 미토콘드리아와 과립형질내세망을 관찰할 수 있었다. 동면기의 원주세포에서는 많은수의 리보소옴을 관찰할 수 있었다. 활동기의 점액세포에서는 크고 많은수의 점액과립과 세포소기관으로 미토콘드리아와 과립형질내세망을 관찰할 수 있었으며 현저한 분비작용을 관찰할 수 있었다. 동면기의 점액세포에서는 수와 크기에서 감소된 점액과립과 활동기보다 증가된 리보소옴을 관찰할 수 있었으며 분비작용은 활동기에 비해 감소하였다.

• IMMUNE NETWORK
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• 제15권1호
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• pp.44-49
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• 2015

Interactions between microbes and epithelial cells in the gastrointestinal tract are closely associated with regulation of intestinal mucosal immune responses. Recent studies have highlighted the modulation of mucosal immunity by microbe-derived molecules such as ATP and short-chain fatty acids. In this study, we undertook to characterize the expression of the ATP-gated $P2X_7$ receptor ($P2X_7R$) on M cells and its role in gastrointestinal mucosal immune regulation because it was poorly characterized in Peyer's patches, although purinergic signaling via $P2X_7R$ and luminal ATP have been considered to play an important role in the gastrointestinal tract. Here, we present the first report on the expression of $P2X_7R$ on M cells and characterize the role of $P2X_7R$ in immune enhancement by ATP or LL-37.

• BMB Reports
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• 제34권2호
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• pp.123-129
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• 2001

Cellular response to ionizing radiation is affected by cell types, radiation doses, and post-irradiation time. Based on the trypan blue dye exclusion assay in normal oral mucosal cells (OM cells), a 48 h post-irradiation was sufffcient and an adequate time point for the evaluation of radiation sensitivity Its $LD_{50}$ was approximately 1.83 Gy To investigate possible biomarkers useful for the biological radiodosimetry of normal epithelial cells (p53, c-fos, cyclin D1, cdc-2, pRb) EGF receptor phosphorylation and Erk activation were evaluated at different radiation doses and different post-irradiation times. From 0.5 Gy, p53 was accumulated in the nucleus of basal cells of the OM raft culture at 4 h post-irradiation and sustained up to 24 h post-irradiation, which suggests that radiation-induced apoptosis or damage repair was not yet completed. The number of p53 positive cells and biosynthesis of p53 were correlated with radiation doses. Both cyclin D1 and c-fos were only transiently induced within 1 h post-irradiation. Cyclin D1 was induced at all radiation doses. However, cfos induction was highest at 0.1 Gy, approximately 7.3 fold more induction than the control, whose induction was reduced in a reverse correlation with radiation dose. The phosphorylation pattern of cdc-2 and pRb were unaffected by radiation. In contrast to A431 tails overexpressing the EGF receptor approximately 8.5 fold higher than normal epithelial, the OM cells reduced the basal level of the EGF receptor phosphorylation in a radiation dose dependent fashion. In conclusion, among radiation-induced biomolecules, the p53 nuclear accumulation may be considered for the future development of a useful marker far biological radiodosimetry in normal epithelial tissue since it was sustained for a longer period and showed a dose response relationship. Specific c-fos induction at a low dose may also be an important finding in this study It needs to be studied further for the elucidation of its possible connection with the low dose radio-adaptive response.

• The Korean Journal of Physiology and Pharmacology
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• 제19권1호
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• pp.1-7
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• 2015

Our previous study has shown berberine prevents damage to the intestinal mucosal barrier during early phase of sepsis in rat through mechanisms independent of the NOD-like receptors signaling pathway. In this study, we explored the regulatory effects of berberine on Toll-like receptors during the intestinal mucosal damaging process in rats. Male Sprague-Dawlay (SD) rats were treated with berberine for 5 d before undergoing cecal ligation and puncture (CLP) to induce polymicrobial sepsis. The expression of Toll-like receptor 2 (TLR 2), TLR 4, TLR 9, the activity of nuclear factor-kappa B ($NF-{\kappa}B$), the levels of selected cytokines and chemokines, percentage of cell death in intestinal epithelial cells, and mucosal permeability were investigated at 0, 2, 6, 12 and 24 h after CLP. Results showed that the tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and interleukin-6 (IL-6) level were significantly lower in berberine-treated rats compared to the control animals. Conversely, the expression level of tight junction proteins, percentage of cell death in intestinal epithelial cells and the mucosal permeability were significantly higher in berberine-treated rats. The mRNA expression of TLR 2, TLR 4, and TLR 9 were significantly affected by berberine treatment. Our results indicate that pretreatment with berberine attenuates tissue injury and protects the intestinal mucosal barrier in early phase of sepsis and this may possibly have been mediated through the TLRs pathway.

• Parasites, Hosts and Diseases
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• 제53권4호
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• pp.371-377
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• 2015

Trichomonas vaginalis induces proinflammation in cervicovaginal mucosal epithelium. To investigate the signaling pathways in $TNF-{\alpha}$ production in cervical mucosal epithelium after T. vaginalis infection, the phosphorylation of PI3K/AKT and MAPK pathways were evaluated in T. vaginalis-infected SiHa cells in the presence and absence of specific inhibitors. T. vaginalis increased $TNF-{\alpha}$ production in SiHa cells, in a parasite burden-dependent and incubation time-dependent manner. In T. vaginalis-infected SiHa cells, AKT, ERK1/2, p38 MAPK, and JNK were phosphorylated from 1 hr after infection; however, the phosphorylation patterns were different from each other. After pretreatment with inhibitors of the PI3K/AKT and MAPK pathways, $TNF-{\alpha}$ production was significantly decreased compared to the control; however, $TNF-{\alpha}$ reduction patterns were different depending on the type of PI3K/MAPK inhibitors. $TNF-{\alpha}$ production was reduced in a dose-dependent manner by treatment with wortmannin and PD98059, whereas it was increased by SP600125. These data suggested that PI3K/AKT and MAPK signaling pathways are important in regulation of $TNF-{\alpha}$ production in cervical mucosal epithelial SiHa cells. However, activation patterns of each pathway were different from the types of PI3K/MAPK pathways.

• Natural Product Sciences
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• 제15권4호
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• pp.185-191
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• 2009

Intestinal epithelial cells (IEC) play an important role in the mucosal immune system. IEC-derived mediators of inflammatory cascades play a principal role in the development of colon inflammation. The aim of this study was to investigate the inhibitory effect of aqueous extracts of Schizandra chinensis fruits (SC-Ex) on the production of inflammatory mediators by the human colonic epithelial cells. HT-29 cells were stimulated with dextran sulfate sodium in the presence or absence of SC-Ex to examine the cytoprotection and production of IL-8 and reactive oxygen species (ROS). It was shown that dextran sulfate sodium (DSS) caused the reduction of cell viability and production of IL-8 and ROS in DSS-treated HT-29 cells. We observed that the treatment of SC-Ex protected significantly cell proliferation from DSS-induced damage in dose-dependent manner. SC-Ex (10 and 100 ${\mu}g$/ml) also suppressed DSS-induced production of IL-8 mRNA and protein. Moreover, DSS-induced ROS production was inhibited markedly by the treatment of 100 ${\mu}g$/ml SC-Ex. These results suggest that SC-Ex has the protective effects on DSS-induced cell damage and the release of inflammatory mediators in the intestinal epithelial cells.

• 한국발생생물학회지:발생과생식
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• 제23권4호
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• pp.305-311
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• 2019

Small intestine has a structure called villi that increases the mucosal surface area for nutrient absorption. Intricate and tight epithelial-mesenchymal interactions are required for villi development. These interactions are regulated by signaling molecules, physical forces, and epithelial deformation. Signaling molecules include hedgehog (Hh), bone morphogenetic protein (BMP) and Wnt ligands. The Hh ligand is expressed from the epithelium and binds to the underlying mesenchymal cells, resulting in aggregation into mesenchymal clusters. The clusters express BMP and Wnt ligands to control its size and spacing between clusters. The clusters then form villi. Despite the fact that the villi formation is studied extensively, we do not have a complete understanding. In addition, the recent study shows there is a great relationship between the overexpression of the Hh signal and development of cancer in the gastrointestinal tract. Therefore, signaling between epithelial and mesenchymal cells and their physical interactions will be discussed on this review.

• 대한수의학회지
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• 제32권1호
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• pp.1-6
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• 1992

The turnover time of the mucosal epithelium in the small intestine(jejunum and ilium) and large interstine(cecum), and the cells in the lamina propria of the small intestine was investigated with the radioautography in mice at various times after single injection of $^3H$-thymidine. Twenty suckling mice were sacrified at each of the following time intervals after injection ; 2 hrs, 1, 3, 5. 7, 14 and 17 days. 1. The labeled index of the epithelial cells in the crypt and the villus of the small intestine averaged 98.7% and 1.3% at 2 hrs, 982% and 1.8% at 1 day, 18.7% and 81.3% at 3 days, 6.3% and 93.7% at 5 days, respectively. The labeled index of the epithelial cells of the crypt-base, the upper-crypt and the mucosal surface in the large intestine averaged 71.8%, 28.2% and 0% at 2 hrs, 45%. 54.2% and 0% at 1 day, 17.2%, 54.5% and 28.2% at 3 days, 10.2%, 32.4% and 57.4% at 5 days, respectively. This result suggested that the turnover time of all the epithelial cells migrating from crypts to villi in the direction of the villus tips was calculated to be less than 5 days, and also the longest turnover time was calculated to be no longer than 7 day. 2. The labeled index of the total cells in the lamina propria of the small intestine averaged 6.2-7% at 2 hrs to 5 days, 4.7% at 7 days 2.6% at 17 days and this index is tend to be decreased moderately at 7 days and severely at 17 days. So this result suggested that the turnover time of the cells with the shorter cycle duration in the lamina propria of the small intestine were less than 5 days and that of the cells with the longer cycle duration more than 17 days.