• The Journal of Korean Society of Virology
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• v.30 no.3
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• pp.161-170
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• 2000

Continuous efforts are being made to find effective therapeutic agents against HIV-1, the causative agents of AIDS. In this study, we developed a cell-based assay system employing a trans-complementation for production of recombinant viruses which are capable of undergoing one round of replication in CD4+ T cells. This assay system was tested for ability to screen the agents that act at late stage of HIV-1 life cycle. The effect of a protease inhibitor on the trans-complementation assay was assessed. Recombinant HIV-1 viruses were prepared from a trans-complementation in the presence of various concentrations of protease inhibitor. Inhibition of single round infection of these recombinant viruses by protease inhibitor was observed to be a dose-dependent manner. Inhibitory effects of a protease inhibitor on HIV-1 Gag polyprotein processing by HIV-1 protease was detected at concentrations of the protease inhibitor compatible with inhibition of virus infection, confirming that the corresponding step was involved in the inhibitory mechanism of this compound. Together, these results provide evidence that a cell-based assay system established in this study can be used to screen the agents that target the late stage of HIV-1 life cycle.

• Journal of Veterinary Science
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• v.24 no.1
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• pp.15.1-15.13
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• 2023

Background: Inactivated vaccines are limited in preventing foot-and-mouth disease (FMD) due to safety problems. Recombinant virus-like particles (VLPs) are an excellent candidate for a novel vaccine for preventing FMD, given that VLPs have similar immunogenicity as natural viruses and are replication- and infection-incompetent. Objectives: The 3C protease and P1 polyprotein of type O FMD virus (FDMV) was expressed in yeast Hansenula polymorpha to generate self-resembling VLPs, and the potential of recombinant VLPs as an FMD vaccine was evaluated. Methods: BALB/c mice were immunized with recombinant purified VLPs using CpG oligodeoxynucleotide and aluminum hydroxide gel as an adjuvant. Cytokines and lymphocytes from serum and spleen were analyzed by enzyme-linked immunosorbent assay, enzyme-linked immunospot assay, and flow cytometry. Results: The VLPs of FMD were purified successfully from yeast protein with a diameter of approximately 25 nm. The immunization of mice showed that animals produced high levels of FMDV antibodies and a higher level of antibodies for a longer time. In addition, higher levels of interferon-γ and CD4⁺ T cells were observed in mice immunized with VLPs. Conclusions: The expression of VLPs of FMD in H. polymorpha provides a novel strategy for the generation of the FMDV vaccine.

• Korean Journal of Veterinary Research
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• v.54 no.4
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• pp.209-218
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• 2014

Experimental autoimmune encephalomyelitis (EAE), an animal model of human multiple sclerosis (MS), reflects pathophysiologic steps in MS such as the influence of T cells and antibodies reactive to the myelin sheath, and the cytotoxic effect of cytokines. Galectin-9 (Gal-9) is a member of animal lectins that plays an essential role in various biological functions. The expression of Gal-9 is significantly enhanced in MS lesions; however, its role in autoimmune disease has not been fully elucidated. To identify the role of Gal-9 in EAE, we measured changes in mRNA and protein expression of Gal-9 as EAE progressed. Expression increased with disease progression, with a sharp rise occurring at its peak. Gal-9 immunoreactivity was mainly expressed in astrocytes and microglia of the central nervous system (CNS) and macrophages of spleen. Flow cytometric analysis revealed that $Gal-9^+CD11b^+$ cells were dramatically increased in the spleen at the peak of disease. Increased expression of tumor necrosis factor (TNF)-R1 and p-Jun N-terminal kinase (JNK) was observed in the CNS of EAE mice, suggesting that TNF-R1 and p-JNK might be key regulators contributing to the expression of Gal-9 during EAE. These results suggest that identification of the relationship between Gal-9 and EAE progression is critical for better understanding Gal-9 biology in autoimmune disease.

• IMMUNE NETWORK
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• v.21 no.4
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• pp.26.1-26.28
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• 2021

Asthma exacerbations are a major cause of intractable morbidity, increases in health care costs, and a greater progressive loss of lung function. Asthma exacerbations are most commonly triggered by respiratory viral infections, particularly with human rhinovirus (hRV). Respiratory viral infections are believed to affect the expression of indoleamine 2,3-dioxygenase (IDO), a limiting enzyme in tryptophan catabolism, which is presumed to alter asthmatic airway inflammation. Here, we explored the detailed role of IDO in the progression of asthma exacerbations using a mouse model for asthma exacerbation caused by hRV infection. Our results reveal that IDO is required to prevent neutrophilic inflammation in the course of asthma exacerbation caused by an hRV infection, as corroborated by markedly enhanced Th17- and Th1-type neutrophilia in the airways of IDO-deficient mice. This neutrophilia was closely associated with disrupted expression of tight junctions and enhanced expression of inflammasome-related molecules and mucin-inducing genes. In addition, IDO ablation enhanced allergen-specific Th17- and Th1-biased CD4⁺ T-cell responses following hRV infection. The role of IDO in attenuating Th17- and Th1-type neutrophilic airway inflammation became more apparent in chronic asthma exacerbations after repeated allergen exposures and hRV infections. Furthermore, IDO enzymatic induction in leukocytes derived from the hematopoietic stem cell (HSC) lineage appeared to play a dominant role in attenuating Th17- and Th1-type neutrophilic inflammation in the airway following hRV infection. Therefore, IDO activity in HSC-derived leukocytes is required to regulate Th17- and Th1-type neutrophilic inflammation in the airway during asthma exacerbations caused by hRV infections.

• Clinical and Experimental Reproductive Medicine
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• v.44 no.3
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• pp.152-158
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• 2017

Objective: To identify the associations between polymorphisms of the 3'-untranslated region (UTR) of methylenetetrahydrofolate reductase (MTHFR) gene, which codes for an important regulatory enzyme primarily involved in folate metabolism, and idiopathic recurrent pregnancy loss (RPL) in Korean women. Methods: The study population comprised 369 RPL patients and 228 controls. MTHFR 2572C > A, 4869C > G, 5488C > T, and 6685T > C 3'-UTR polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis or by TaqMan allelic discrimination assays. Natural killer cell proportions were determined by flow cytometry. Results: The MTHFR 2572-5488-6685 (A-C-T) haplotype had an adjusted odds ratio of 0.420 (95% confidence interval, 0.178-0.994; p= 0.048) for RPL. Analysis of variance revealed that MTHFR 4869C > G was associated with altered $CD56^+$ natural killer cell percentages (CC, $17.91%{\pm}8.04%$; CG, $12.67%{\pm}4.64%$; p= 0.024) and folate levels (CC, $12.01{\pm}7.18mg/mL$; CG, $22.15{\pm}26.25mg/mL$; p= 0.006). Conclusion: Variants in the 3'-UTR of MTHFR are potential biomarkers for RPL. However, these results should be validated in additional studies of ethnically diverse groups of patients.

• Journal of Microbiology and Biotechnology
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• v.26 no.11
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• pp.1881-1890
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• 2016

Manganese superoxide dismutase (MnSOD) is a vital enzyme that protects cells from free radicals through eliminating superoxide radicals ($O^{2-}$). Hirudin, a kind of small active peptide molecule, is one of the strongest anticoagulants that can effectively cure thrombus diseases. In this study, we fused Hirudin to the C terminus of human MnSOD with the GGGGS linker to generate a novel dual-feature fusion protein, denoted as hMnSOD-Hirudin. The hMnSOD-Hirudin gene fragment was cloned into the pET15b (SmaI, CIAP) vector, forming a recombinant pET15b-hMnSOD-Hirudin plasmid, and then was transferred into Escherichia coli strain Rosetta-gami for expression. SDS-PAGE was used to detect the fusion protein, which was expected to be about 30 kDa upon IPTG induction. Furthermore, the hMnSOD-Hirudin protein was heavily detected as a soluble form in the supernatant. The purification rate observed after Ni NTA affinity chromatography was above 95%. The hMnSOD-Hirudin protein yield reached 67.25 mg per liter of bacterial culture. The identity of the purified protein was confirmed by western blotting. The hMnSOD-Hirudin protein activity assay evinced that the antioxidation activity of the hMnSOD-Hirudin protein obtained was $2,444.0{\pm}96.0U/mg$, and the anticoagulant activity of the hMnSOD-Hirudin protein was $599.0{\pm}35.0ATU/mg$. In addition, in vitro bioactivity assay showed that the hMnSOD-Hirudin protein had no or little cytotoxicity in H9c2, HK-2, and H9 (human $CD_4{^+}$, T cell) cell lines. Transwell migration assay and invasion assay showed that the hMnSOD-Hirudin protein could suppress human lung cancer 95-D cell metastasis and invasion in vitro.

• Development and Reproduction
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• v.15 no.4
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• pp.373-383
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• 2011

Tributyltin (TBT) is one of endocrine disrupters which are known as having similar function to sex steroid hormone inducing apoptosis in various tissues of rodents. Recently, it has been reported that TBT induces apoptosis in thymus causing the decreased thymic function, but little is known about the mechanism. To elucidate the mechanism, three-week-old SD female rats were orally administrated with TBT 1, 10, and 25 mg per body weight (kg) and sesame oil as a control for 7 days. On day 8, the thymi were obtained and weighed, and then the number of thymocytes was counted. We also performed H&E staining, TUNEL assay, and Annexin V flow cytometric analysis to examine the apoptosis rates and the structure in the thymus. Next, we investigated the adipogenesis and apoptosis-related mRNA expression levels in the thymi by real-time PCR. The thymic weight and the number of thymocytes were decreased by TBT in a dose-dependent manner. As a result of the H&E staining, the boundary between cortical and medullary area was blurred in the thymi of TBT treated rats compared to those of controls. In the results of TUNEL assay and Annexin V flow cytometric analysis, apoptosis rates in the thymus were increased after TBT treatment. The expression levels of thymic epithelial cell marker genes such as EVA, KGF, AIRE, and IL-7 were significantly decreased in the thymi of TBT treated rats, but $PPAR{\gamma}$, aP2, PEPCK, and CD36 were significantly increased. The expression of $TNF{\alpha}$ and TNFR1 as apoptosis-related genes also was significantly increased after TBT treatment. The present study demonstrates that TBT can increase the expression of adipogenesis and apoptosis-related genes leading to apoptosis in the thymus. These results suggest that the increased adipogenesis of thymus by TBT exposure might induce apoptosis in the thymus resulting in a loss in thymic immune function.

• Tuberculosis and Respiratory Diseases
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• v.46 no.1
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• pp.44-52
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• 1999

Background : Airway infiltration by inflammatory cells, particularly of eosinophils, is one of the characteristic features of asthma. Several mechanisms for the recruitment of eosinophil is focused on the CD4+ T lymphocyte for the preferential production of Th2-c1erived cytokines. Interleukin-10(IL-10) is identified cytokine with potent antiinflammatory activity. This molecule has been shown to inhibit the release of cytokine from inflammatory cells including Th2 cell, and also to inhibit eosinophil survival. We therefore attempted to determine whether decreased synthesis of IL-10 in the lung of bronchial asthma may contribute to inflammation that is characteristics of this dease. Method: Subjects were patients with bronchial asthma(n=23) and normal controls(n=11). IL-10 produced from peripheral mononuclear cell(PBMC) and in bronchoalveolar lavage(BAL) fluid was measured by ELISA method. Degree of bronchial inflammation was assessed by total cell counts and eosinophil percents in BAL fluid, eosinophil infiltration on bronchial biopsy tissue and $PC_{20}$ for methacholine. Results: The IL-10 level produced by PBMC and in BAL fluid from patient with bronchial asthma were not different with normal controls(respectively, $901.6\pm220.4$ pg/ml, $810.9\pm290.8$ pg/ml for PBMC, $24.5\pm9.5$ pg/mL $30.5\pm13.5$ pg/ml for BAL fluid p>0.05). There were significant negative correlation between IL-10 in BAL fluid and eosinophil percents in BAL fluid or degree of eosinophil infiltration in bronchial biopsy (respectively r=-0.522, r=-0.4486 p<0.05). However there was no difference of IL-10 level according to $PC_{20}$ for methacholine. There were no correlation between IL-10 production by PBMC and peripheral blood eosinophil counts or serum eosinophilic cationic protein levels(respectively r=0.1146, r=0.0769 p>0.05). Conclusion: These observation suggest that IL-10 may participate but not acts the crucial role in regulation of the airway inflammation in bronchial asthma.

• Clinical and Experimental Pediatrics
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• v.53 no.2
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• pp.215-221
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• 2010

Purpose : Interleukin-17 (IL-17) is produced by activated CD4+T cells and exhibits pleiotropic biological activity on various cell types. IL-17 was reported to be involved in the immunoregulatory response in IgA nephropathy (IgAN). Our aim was to investigate the association between single-nucleotide polymorphisms (SNPs) in IL-17 receptor A (IL-17RA) gene and childhood IgAN. Methods : We analyzed the SNPs in the IL-17RA in 156 children with biopsy-proven IgAN and 245 healthy controls. We divided the IgAN patients into 2 groups and compared them with respect to proteinuria (${\leq}4$ and >$4mg/m^2/h$, ${\leq}40$ and >$40mg/m^2/h$, respectively) and the presence of pathological levels of biomarkers of diseases such as interstitial fibrosis, tubular atrophy, or global sclerosis. Results : No difference was observed between the SNP genotypes rs2895332, rs1468488, and rs4819553 between IgAN patients and control subjects. In addition, no significant difference was observed between allele frequency of SNPs rs2895 332, rs1468488, and rs4819553 between patients in the early and advanced stage of the disease. However, significant difference was observed between the genotype of SNP rs2895332 between patients with proteinuria (>$4mg/m^2/h$) and those without proteinuria (codominant model OR 0.36, 95% CI 0.19-.66, P <0.001; dominant model OR 0.35, 95% CI 0.17-.69 P =0.002; recessive model OR 0.12, 95% CI 0.01-.06 P =0.025). Conclusion : Our results indicate that the SNP in IL-17RA (rs2895332) may be related to the development of proteinuria in IgAN patients.

• Journal of Nutrition and Health
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• v.52 no.6
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• pp.515-528
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• 2019

Purpose: This study examined the immunological activity and optimized the mixture conditions of Sargassum horneri (S. horneri) extracts in vitro and in vivo models. Methods: S. horneri was extracted using three different methods: hot water extraction (HWE), 50% ethanol extraction (EE), and supercritical fluid extraction (SFE). Splenocyte proliferation and cytokine production (Interleukin-2 and Interferon-γ) were measured using a WST-1 assay and enzyme-linked immunosorbent assay, respectively. The levels of nitric oxide and T cell activation production were measured using a Griess assay and flow cytometry, respectively. The natural killer (NK) cell activity was determined using an EZ-LDH kit. Results: Among the three different types of extracts, HWE showed the highest levels of splenocyte proliferation and cytokine production in vitro. In the animal model, three different types of extracts were administrated for 14 days (once/day) at 50 and 100 mg/kg body weight. HWE and SFE showed a high level of splenocyte proliferation and cytokine production in the with and without mitogen-treated groups, whereas EE administration did not induce the splenocyte activation. When RAW264.7 macrophage cells were treated with different mixtures (HWE with 5, 10, 15, 20% of SFE) to determine the optimal mixture ratio of HWE and SFE, the levels of nitric oxide and cytokine production increased strongly in the HWE with 5% and 10% of SFE containing group. In the animal model, HWE with 5% and 10% of SFE mixture administration increased the levels of splenocyte proliferation, cytokine production, and activated CD4⁺ cell population significantly, with the highest level observed in the HWE with 5% of SFE group. Moreover, the NK cell activity was increased significantly in the HWE with 5% of SFE mixture-treated group compared to the control group. Conclusion: The optimal mixture condition of S. horneri with immune-enhancing activity is the HWE with 5% of SFE mixture. These results confirmed that the extracts of S. horneri and its mixtures are potential candidate materials for immune enhancement.