• IMMUNE NETWORK
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• v.9 no.2
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• pp.58-63
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• 2009

Background: T cell immunoglobulin and mucin domain containing 3 protein (Tim-3) expressed on terminally differentiated Th1 cells plays a suppressive role in Th1-mediated immune responses. Recently, it has been shown that N-glycosylation affects the binding activity of the Tim-3-Ig fusion protein to its ligand, galectin-9, but the binding properties of non-glycosylated Tim-3 on $CD4^+CD25^+$T cells has not been fully examined. In this study, we produced recombinant Tim-3-Ig fusion proteins in different cellular sources and its N-glycosylation mutant forms to evaluate their binding activities to $CD4^+CD25^+$T cells. Methods: We isolated and cloned Tim-3 cDNA from BALB/C mouse splenocytes. Then, we constructed a mammalian expression vector and a prokaryotic expression vector for the Tim-3-Ig fusion protein. Using a site directed mutagenesis method, plasmid vectors for Tim-3-Ig N-glycosylation mutant expression were produced. The recombinant protein was purified by protein A sepharose column chromatography. The binding activity of Tim-3-Ig fusion protein to $CD4^+CD25^+$T cells was analyzed using flow cytometry. Results: We found that the nonglycosylated Tim-3-Ig fusion proteins expressed in bacteria bound to $CD4^+CD25^+$T cells similarly to the glycosylated Tim-3-Ig protein produced in CHO cells. Further, three N-glycosylation mutant forms (N53Q, N100Q, N53/100Q) of Tim-3-Ig showed similar binding activities to those of wild type glycosylated Tim-3-Ig. Conclusion: Our results suggest that N-glycosylation of Tim-3 may not affect its binding activity to ligands expressed on $CD4^+CD25^+$T cells.

• IMMUNE NETWORK
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• v.7 no.4
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• pp.173-178
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• 2007

Background: We studied the role for expression of CD40 and CD40L by CD4 and CD8 T cells in the generation of CD8 T cell response to minor histocompatibility antigen, H60. H60 is a cellular antigen to which CD8 responses require CD4 T cell help. Methods: CD40- or CD40L-deficient mice were adoptively transferred with normal CD4 or CD8 T cells or with memory CD4 or CD8 T cells, and were immunized with male H60 congenic splenocytes to induce CD8 T cell response to H60. Peripheral blood CD8 T cell from the immunized mice were stained with the H60 tetramer. Results: CD8 T cell response to H60 was not induced in both CD40- and CD40L-deficient mice. Adoptive transfer of $CD40^{+/+}$ CD8 T cells into CD40-deficient mice did not compensate the defect in inducing CD8 T cell response to H60, while the H60-specific CD8 T cells were activated in the CD40-deficient mice that were adoptively transferred with $CD40^{+/+}$ CD4 T cells. Adoptive transfer of $CD40L^{+/+}$ CD4 T cells into CD40L-deficient mice induced primary CD8 T cell response for H60 and the presence of $CD40L^{+/+}$ CD4 T cells was required even for memory CD8 T cells response to H60. Conclusion: Our results suggest that the CD40-CD40L interaction mediates the delivery of CD4 T cell help to naive and memory H60-specific CD8 T cells. While the expression of CD40L by CD4 T cells is essential, signaling through CD40 on CD8 T cells is not required for the induction of CD8 T cell response to H60.

• Proceedings of the Korea Information Assurance Society Conference
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• 2004.05a
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• pp.103-108
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• 2004

A Home Location Register(HLR) database system manages each subscriber's location information, which continuously changes in a cellular network. For this purpose, the HLR database system provides table management, index management, and backup management facilities. In this thesis, I propose using a two-level index method for the mobile directory number(MDN) as a suitable method and a chained bucket hashing method for the electronic serial number(ESN). Both the MDN and the ESN are used as keys in the HLR database system. I also propose an efficient backup method that takes into account the characteristics of HLR database transactions. The retrieval speed and the memory usage of the two-level index method are better than those of the T-tree index method. The insertion and deletion overhead of the chained bucket hashing method is less than that of the modified linear hashing method. In the proposed backup method, I use two kinds of dirty flags in order to solvethe performance degradation problem caused by frequent registration-location operations. I also propose using additional attributes in the HLR database scheme for location information secrecy as a suitable security method.

• IMMUNE NETWORK
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• v.12 no.6
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• pp.296-300
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• 2012

Silica nanoparticles, which are applicable in many industrial fields, have been reported to induce cellular changes such as cytotoxicity in various cells and fibrosis in lungs. Because the immune system is the primary targeting organ reacting to internalized exogenous nanoparticles, we tried to figure out the immunostimulatory effect of silica nanoparticles in macrophages using differently sized silica nanoparticles. Using U937 cells we assessed cytotoxicity by CCK-8 assay, ROS generation by CM-$H_2DCFDA$, intracellular $Ca^{{+}{+}}$ levels by staining with Fluo4-AM and IL-8 production by ELISA. At non-toxic concentration, the intracellular $Ca^{{+}{+}}$ level has increased immediately after exposure to 15 nm particles, not to larger particles. ROS generation was detected significantly in response to 15 nm particles. However, all three different sizes of silica nanoparticles induced IL-8 production. 15 nm silica nanoparticles are more stimulatory than larger particles in cytotoxicity, intracellular $Ca^{{+}{+}}$ increase and ROS generation. But IL-8 production was induced to same levels with 50 or 100 nm particles. Therefore, IL-8 production induced by silica nanoparticles may be dependent on other mechanisms rather than intracellular $Ca^{{+}{+}}$ increase and ROS generation.

• IMMUNE NETWORK
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• v.10 no.5
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• pp.173-180
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• 2010

Background: APRIL, originally known as a cytokine involved in B cell survival, is now known to regulate the inflammatory activation of macrophages. Although the signal initiated from APRIL has been demonstrated, its role in cellular activation is still not clear due to the presence of BAFF, a closely related member of TNF superfamily, which share same receptors (TACI and BCMA) with APRIL. Methods: Through transfection of siRNA, BAFF-deficient THP-1 cells (human macrophage-like cells) were generated and APRIL-mediated inflammatory activities were tested. The expression patterns of APRIL were also tested in vivo. Results: BAFF-deficient THP-1 cells responded to APRIL-stimulating agents such as monoclonal antibody against APRIL and soluble form of TACI or BCMA. Furthermore, co-incubation of the siBAFF-deficient THP-1 cells with a human B cell line (Ramos) resulted in an activation of THP-1 cells which was dependent on interactions between APRIL and TACI/BCMA. Immunohistochemical analysis of human pathologic samples detected the expression of both APRIL and TACI in macrophage-rich areas. Additionally, human macrophage primary culture expressed APRIL on the cell surface. Conclusion: These observations indicate that APRIL, which is expressed on macrophages in pathologic tissues with chronic inflammation, may mediate activation signals through its interaction with its counterparts via cell-to-cell interaction.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.28 no.1
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• pp.68-72
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• 2006

Mucoepidermoid carcinoma is one of the most common malignant salivary gland neoplasm. It occurs over a wide age range, and is most common in the parotid gland and usually appears as an asymptomatic swelling. Pain or facial nerve palsy may develop. Minor salivary gland tumors also typically appear as asymptomatic swellings, which are sometimes fluctuant and have blue or red color that can be mistaken clinically for a mucocele. Histopathologically the mucoepidermoid carcinoma is composed of a mixture of mucous-producing cells and squamous (epidermoid) cells. Low-grade tumors show prominent cyst formation, minimal cellular atypia, and relatively high proportion of mucous cells. Mucoepidermoid carcinoma of the minor salivary glands are treated usually by assured surgical excision. For low-grade neoplasm, only a modest margin of surrounding normal tissue may need to be removed, but high-grade or large tumors warrant wider resection. Postoperative radiation therapy also may be used for more aggressive tumors. Mucoepidermoid carcinoma of the oral minor salivary glands generally have a good prognosis, because they are mostly low-to intermediate grade tumors. We present a case of mucoepidermoid carcinoma managed with surgical enucleation and postoperative irradiation and a good clinical result with review of literatures.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.34 no.4
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• pp.239-245
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• 2012

Purpose: Vascular endothelial growth factor (VEGF) plays a key role in tumor angiogenesis and lymphangiogenesis including induction of endothelial cell proliferation, migration and capillary tube formation. E7080 (S1164, Selleck chemical, Houston, TX, USA) is a muti-targeted kinase inhibitor, which targets VEGF receptor-2, 3 (VEGFR-2, 3) and inhibits survival and proliferation of tumor cell. The purpose of this study was to determine the anti-tumor effect of E7080 on oral squamous cell carcinoma. Methods: An oral squamous cell carcinoma cell line, SCC-9 was used in this study. E7080 was applied to SCC-9 cells by 3 different concentrations (1, 5, 10 ${\mu}g/mL$). Control means no application of E7080. The cellular growth was evaluated by real-time cell electronic sensing and MTT assay. The signal transduction was evaluated by Western blotting. Results: In experimental group, SCC-9 cell proliferation was decreased and the VEGFR-3 downstream pathways were inhibited compared with control. Furthermore, increasing the concentration of E7080, the ability of E7080 to disturbance of SCC-9 cell proliferation was increased. Conclusion: Proliferation of SCC-9 cells was inhibited by E7080, which was through by inhibition of VEGFR-3 downstream pathway. In vivo study with E7080 will be required to provide therapeutic benefits in oral squamous cell carcinoma.

• Journal of Gastric Cancer
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• v.3 no.3
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• pp.145-150
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• 2003

Purpose: The p53 tumor suppressor gene is believed to play a pivotal role in preventing the uncontrolled cellular growth characteristic of cancer. Mutation of the p53 gene represent one of the most common genetic alterations in human cancers, and the acquisition of such defects is strongly associated with tumor progression and metastasis. The aim of this study was to evaluate the relation between p53 immunoreactivity and the mutation of p53 gene in gastric adenocarcinoma obtained by laser capture microscope. Materials and Methods: Formalin fixed paraffin embedded tissue specimens were obtained from 20 patients who underwent surgery for gastric cancer. According to UICC TNM system, 3 of the cases were Ia, 2 cases II, 4 cases IIIa, 5 cases IIIb, and 6 cases IV. Results: Immunohistochemical staining revealed eight cases as negative (less than $10\%$), twelve cases as postive (more than $10\%$). The locations of mutations were as follows; 7 cases had point mutation at exon 4, and 3 cases point mutation at exon 8. There was no mutation at exon 5, 6, 7 and 9. The mutation was observed in 1 case out of 8 p53 oncoprotein negative cases, and 7 cases out of 12 p53 positive cases. The mutation was more common in p53 positive cases (P<0.05), However, there was no significant correlation between p53 mutation observed by DNA sequencing after laser capture microdissection and expression of p53 oncoprotein. Conclusion: These result suggest that he expression of p53 oncoprotein not to be related to the mutation of p53 gene at exons 4 through 9 in gastric cancer.

• Journal of Gastric Cancer
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• v.2 no.2
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• pp.101-104
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• 2002

Schwannoma of the stomach is a rare controversial neoplasm which requires extensive studies to clarify its nature as a stromal tumor or leiomyoma. We describe the pathologic, immunohistochemical, and ultrastructural characteristics of schwannoma of the stomach in a 33-year-old woman. The tumor was a well-circumscribed submucosal mass located in the posterior wall of the midbody of the stomach. Microscopically, the cells were made up of fasciculating bundles of spindle cells featured with peripheral lymphoid cell cuffing. The tumor cells revealed a diffuse, strong immunoreactivity to S-100 protein and vimentin, but were negative to desmin and smooth muscle actin. They also had a focal positive reaction to glial fibrillary acidic protein. Ultrastructurally, many tumor cells showed a number of thin, elongated and interdigitating dendritic-cell-like processes, distinctly uniformed basal laminae, frequent cellular attachments, and microfilaments. These findings support the schwannian nature of the tumor.

• Molecules and Cells
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• v.40 no.12
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• pp.916-924
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• 2017

MicroRNAs are widely involved in the pathogenesis of cardiovascular diseases through regulating gene expression via translational inhibition or degradation of their target mRNAs. Recent studies have indicated a critical role of microRNA-206 in myocardial ischaemia-reperfusion (I/R) injury. However, the function of miR-206 in myocardial I/R injury is currently unclear. The present study was aimed to identify the specific role of miR-206 in myocardial I/R injury and explore the underlying molecular mechanism. Our results revealed that the expression level of miR-206 was significantly decreased both in rat I/R group and H9c2 cells subjected to hypoxia/reoxygenation (H/R) compared with the corresponding control. Overexpression of miR-206 observably decreased infarct size and inhibited the cardiomyocyte apoptosis induced by I/R injury. Furthermore, bioinformatics analysis, luciferase activity and western blot assay proved that $Gadd45{\beta}$ (growth arrest DNA damage-inducible gene $45{\beta}$) was a direct target gene of miR-206. In addition, the expression of pro-apoptotic-related genes, such as p53, Bax and cleaved caspase3, was decreased in association with the down-regulation of $Gadd45{\beta}$. In summary, this study demonstrates that miR-206 could protect against myocardial I/R injury by targeting $Gadd45{\beta}$.