• IMMUNE NETWORK
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• v.10 no.4
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• pp.126-134
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• 2010

Background: $CD8^+$ T cells contribute to the clearance of Hepatitis B virus (HBV) infection and an insufficient $CD8^+$ T cell response may be one of the major factors leading to chronic HBV infection. Since the HBx antigen of HBV can up-regulate cellular expression of several immunomodulatory molecules, we hypothesized that HBx expression in hepatocytes might affect $CD8^+$ T cell activity. Methods: We analyzed the activation and apoptosis of $CD8^+$ T cells co-cultured with primary hepatocytes rendered capable of expressing HBx by recombinant baculovirus infection. Results: Expression of HBx in hepatocytes induced low production of $interferon-{\gamma}$ and apoptosis of CD8+ T cells, with no effect on CD8 T cell proliferation. However, transcriptional levels of H-2K, ICAM-1 and PD-1 ligand did not correlate with HBx expression in hepatocytes. Conclusion: Our results suggest that HBx may inhibit $CD8^+$ T cell response by regulation of $interferon-{\gamma}$ production and apoptosis.

• IMMUNE NETWORK
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• v.14 no.2
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• pp.67-72
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• 2014

The herpes virus entry mediator (HVEM) is a member of the tumor necrosis factor receptor superfamily (TNFRSF), and therefore it is also known as TNFRSF14 or CD270 (1,2). In recent years, we have focused on understanding HVEM function in the mucosa of the intestine, particularly on the role of HVEM in colitis pathogenesis, host defense and regulation of the microbiota (2-4). HVEM is an unusual TNF receptor because of its high expression levels in the gut epithelium, its capacity to bind ligands that are not members of the TNF super family, including immunoglobulin (Ig) superfamily members BTLA and CD160, and its bi-directional functionality, acting as a signaling receptor or as a ligand for the receptor BTLA. Clinically, Hvem recently was reported as an inflammatory bowel disease (IBD) risk gene as a result of genome wide association studies (5,6). This suggests HVEM could have a regulatory role influencing the regulation of epithelial barrier, host defense and the microbiota. Consistent with this, using mouse models, we have revealed how HVEM is involved in colitis pathogenesis, mucosal host defense and epithelial immunity (3,7). Although further studies are needed, our results provide the fundamental basis for understanding why Hvem is an IBD risk gene, and they confirm that HVEM is a mucosal gatekeeper with multiple regulatory functions in the mucosa.

• BMB Reports
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• v.35 no.6
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• pp.583-589
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• 2002

The signal transducer and activator of transcription (STAT)1 is a cytoplasmic-transcription factor that is phosphorylated by Janus kinases (Jak) in response to interferon $\gamma$ (IFN-$\gamma$). The phosphorylated STAT1 translocates to the nucleus, where it turns on specific sets of IFN-$\gamma$-inducible genes, such as the interferon regulatory factor (IRF)-1. We show here that gamma irradiation reduces the IFN-$\gamma$ mRNA expression. The inhibition of the STAT1 phosphorylation and the IRF-1 expression by gamma irradiation was also observed. In contrast, the mRNA levels of IL-5 and transcription factor GATA-3 were slightly induced by gamma irradiation when compared to the non-irradiated sample. Furthermore, we detected the inhibition of cell-mediated immunity by gamma irradiation in the allogenic-mixed lymphocytes' reaction (MLR). These results postulate that gamma irradiation induces the polarized-Th2 response and interferes with STAT1 signals, thereby causing the immunosuppression of the Th1 response.

• Clinical and Experimental Reproductive Medicine
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• v.44 no.1
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• pp.1-7
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• 2017

The task force of the Korean Society for Reproductive Immunology recommends intravenous immunoglobulin G treatment in women with reproductive failure, including recurrent pregnancy loss and/or repeated implantation failure, who show cellular immune factors such as abnormal natural killer cell levels, natural killer cell cytotoxicity, and/or type 1 T helper immunity.

• Toxicological Research
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• v.13 no.3
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• pp.247-250
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• 1997

We have studied cytotoxicity of S-nitroso-N-acetyl- N-DL-penicillamine(SNAP), a Nitric oxide (NO)-releasing compound, in RAW264.7 macrophages. SNAP is cytotoxic to RAW264.7 cells in a concentration-dependent manner. PMA(200 nM) stimulated cells to produce superoxide anton radical($O_2^{-\cdot}$) and caused a little loss of RAW264.7 cell viability for 12 hr and diminished the cytotoxicity of SNAP. The mechanism by which PMA can protect cells against NO-mediated cytotoxicity was studied by peroxynitrite-enhanced chemiluminescence method. Observed results suggested that $O_2^{-\cdot}$ produced by PMAstimulated RAW264.7 cells may quench NO released by SNAP and reduce NO, thus attenuating NO-related damages.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.3
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• pp.863-868
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• 2015

Background: Artemisia species are important medicinal plants throughout the world. The present in vitro study, using a sesquiterpene lactone-bearing fraction prepared from Artemisia khorassanica (SLAK), sought to investigate anti-cancer properties of this plant and elucidate potential underlying mechanisms for the effects. Materials and Methods: Anti-cancer potential was evaluated by toxicity against human melanoma and fibroblast cell lines. To explore the involved pathways, pattern of any cell death was determined using annexin-V/PI staining and also the expression of Bax and cytochrome c was investigated by Western blotting. Results: The results showed that SLAK selectively caused a concentration-related inhibition of proliferation of melanoma cells that was associated with remarkable increase in early events and over-expression of both Bax and cytochrome c. Conclusions: The current experiment indicates that Artemisia may have anti-cancer activity. We anticipate that the ingredients may be employed as therapeutic candidates for melanoma.

• IMMUNE NETWORK
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• v.8 no.3
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• pp.75-81
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• 2008

Background: Platelets take part in repairing the lesions of endothelial damage. To understand the molecular mechanism of this process, we tested the hypothesis that CD154 expressed on activated platelets stimulates proliferation of human endothelial cells. Methods: The expression levels of CD154 and CD40 on platelets and endothelial cells, respectively, were measured by flow cytometry and confocal microscopy. Function-blocking monoclonal antibody against CD154 was developed after immunization with CD154-transfected L cells. Results: An anti-CD40 agonist antibody and soluble CD154 both induced significant proliferation of endothelial cells. In addition, a function-blocking anti-CD154 antibody inhibited the platelet-induced proliferation of endothelial cells, indicating that the CD154-CD40 pathway is involved in these cellular interactions. An anti-VEGF antibody failed to inhibit the proliferation. This, in addition to the fact that very small amounts of VEGF are released from platelets or endothelial cells, suggests that VEGF does not play an important role in the platelet-stimulated proliferation of endothelial cells. Conclusion: Our results indicate that platelets induce proliferation of endothelial cells by CD154-CD40 interactions independently of VEGF.

• The Journal of Korean Medicine
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• v.32 no.4
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• pp.68-74
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• 2011

Objective: The purpose of this study is to expatiate on high performance thin layer chromatography (HPTLC) as a simple, easy and scientific method for evaluation and standardization of herbal formulae. Methods: Through retrieving HPTLC application for herbal formulae in the literatures, the current situation of HPTLC application, and potential as well as limitation of HPTLC as a standardization method for multi-herbal drug was studied. Results: HPTLC is a speedy, inexpensive and well-operable tool for possessing multi-capability on component identification, separation, quantification and purification compared to other methods, such as high performance liquid chromatography (HPLC), gas chromatography (GC). Conclusions: HPTLC is considered as an available and convenient method for quality control and standardization of multi-herbal drugs. Thereby, this method could be recommended to widely applicate in the traditional Korean medicine.

• The Journal of Korean Medicine
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• v.31 no.5
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• pp.12-32
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• 2010

Objective: This study aimed to review herbal remedy-based RCTs on cancer patients in order to produce helpful information for clinical study of herbal medicine in the future. Methods: We collected all RCTs using herbal remedies on cancer patients from Pubmed and Cochrane databases until November 1st, 2009. Elementary information such as nation where performed, clinical question, design, randomization, double-blinding and allocation concealment were analyzed. Results: 153 RCTs were finally selected. 119 RCTs were conduced in China while only 2 were done in Korea. The most frequent targeted cancer was lung cancer as 29 RCTs. The main clinical questions included improvement of quality of life, elongation of survival rate and regression of tumor being 83, 62 and 55 respectively. 112 RCTs used herbal remedies with western therapy. Adequate methods for randomization and allocation concealment were found in 37% and 10% of trials respectively. Conclusions: We found that herbal remedies are used on cancer patients in aspects of both caring for the human body and tumor treatment itself. The study might provide us useful data for cancer-related clinical study using herbal remedies in the future.

• Archives of Pharmacal Research
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• v.18 no.6
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• pp.396-401
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• 1995

As a part of trials to develop the antitumor agent from tannins isolated from plants, the antitumor activity of peduculagin, an ellagitannin, isolated from Alnus hirsuta var. microphylla was examined in vitro and in vivo. In vitro, the cytotoxicity was determined by 0.4% typanblue dye exclusion method. peduculagin showed the dose-dependent cytotoxicity against human chronic myelogenous leukemia (K-562), human promyelocytic leukemia (HL-60), mouse lymphoid neoplasm (P388), mouse lymphocytic leukemia (L1210) and mouse sarcoma 180(S180) cell lines. $ED_{50}\; values\; (ED_{50})$ of each cell line were 5.30, 0.92, 2.78, 9.35 and $1.38 \mug/ml$ respectively. The most sensitive cell line was HL-60. In vivo, pedunculagin was administered to ICR mouse with the doses of 50 and $100{\;}{\mu}g/ml$intraperitoneally once at 20 days before S180 inoculation. peduculagin showed the antitumor activity and its T/C ratio (%) was 120.82% in the group of both concentrations.