• IMMUNE NETWORK
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• 제21권4호
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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.

• IMMUNE NETWORK
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• 제21권2호
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• pp.14.1-14.17
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• 2021

Scrub typhus develops after the individual is bitten by a trombiculid mite infected with Orientia tsutsugamushi. Since it has been reported that pneumonia is frequently observed in patients with scrub typhus, we investigated whether intranasal (i.n.) vaccination with the outer membrane protein of O. tsutsugamushi (OMPOT) would induce a protective immunity against O. tsutsugamushi infection. It was particular interest that when mice were infected with O. tsutsugamushi, the bacteria disseminated into the lungs, causing pneumonia. The i.n. vaccination with OMPOT induced IgG responses in serum and bronchoalveolar lavage (BAL) fluid. The anti-O. tsutsugamushi IgA Abs in BAL fluid after the vaccination showed a high correlation of the protection against O. tsutsugamushi. The vaccination induced strong Ag-specific Th1 and Th17 responses in the both spleen and lungs. In conclusion, the current study demonstrated that i.n. vaccination with OMPOT elicited protective immunity against scrub typhus in mouse with O. tsutsugamushi infection causing subsequent pneumonia.

• IMMUNE NETWORK
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• 제21권6호
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• pp.38.1-38.8
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• 2021

Recently, a new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (B.1.1.529) Omicron variant originated from South Africa in the middle of November 2021. SARS-CoV-2 is also called coronavirus disease 2019 (COVID-19) since SARS-CoV-2 is the causative agent of COVID-19. Several studies already suggested that the SARS-CoV-2 Omicron variant would be the fastest transmissible variant compared to the previous 10 SARS-CoV-2 variants of concern, interest, and alert. Few clinical studies reported the high transmissibility of the Omicron variant but there is insufficient time to perform actual experiments to prove it, since the spread is so fast. We analyzed the SARS-CoV-2 Omicron variant, which revealed a very high rate of mutation at amino acid residues that interact with angiostatin-converting enzyme 2. The mutation rate of COVID-19 is faster than what we prepared vaccine program, antibody therapy, lockdown, and quarantine against COVID-19 so far. Thus, it is necessary to find better strategies to overcome the current crisis of COVID-19 pandemic.

• IMMUNE NETWORK
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• 제22권4호
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• pp.34.1-34.19
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• 2022

Osteoarthritis (OA) is the most common form of arthritis associated with ageing. Vitamin D has diverse biological effect on bone and cartilage, and observational studies have suggested it potential benefit in OA progression and inflammation process. However, the effect of vitamin D on OA is still contradictory. Here, we investigated the therapeutic potential of vitamin D in OA. Six-week-old male Wistar rats were injected with monosodium iodoacetate (MIA) to induce OA. Pain severity, cartilage destruction, and inflammation were measured in MIA-induced OA rats. Autophagy activity and mitochondrial function were also measured. Vitamin-D (1,25(OH)₂D3) and celecoxib were used to treat MIA-induced OA rats and OA chondrocytes. Oral supplementation of vitamin D resulted in significant attenuations in OA pain, inflammation, and cartilage destruction. Interestingly, the expressions of MMP-13, IL-1β, and MCP-1 in synovial tissues were remarkably attenuated by vitamin D treatment, suggesting its potential to attenuate synovitis in OA. Vitamin D treatment in OA chondrocytes resulted in autophagy induction in human OA chondrocytes and increased expression of TFEB, but not LC3B, caspase-1 and -3, in inflamed synovium. Vitamin D and celecoxib showed a synergistic effect on antinociceptive and chondroprotective properties in vivo. Vitamin D showed the chondroprotective and antinociceptive property in OA rats. Autophagy induction by vitamin D treatment may be a promising treatment strategy in OA patients especially presenting vitamin D deficiency. Autophagy promoting strategy may attenuate OA progression through protecting cells from damage and inflammatory cell death.

• IMMUNE NETWORK
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• 제22권4호
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• pp.35.1-35.16
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• 2022

Tobacco smoking (TS) has been known as one of the most potent risk factors for airway inflammatory diseases. However, there has been a paucity of information regarding the immunologic alteration mediated by TS in patients with chronic rhinosinusitis with nasal polyps (CRSwNP). To identify the effect of TS, we harvested human tissue samples (never smoker: n=41, current smoker: n=22, quitter: n=23) and analyzed the expression of epithelial-derived cytokines (EDCs) such as IL-25, IL-33, and thymic stromal lymphopoietin. The expressions of Th2 cytokines and total serum IgE showed a type-2 inflammatory alteration by TS. In addition, the epithelial marker E-cadherin and epithelial-mesenchymal transition (EMT)-associated markers (N-cadherin, α-SMA, and vimentin) were evaluated. Histological analysis showed that EDC expressions were upregulated in the current smoker group and downregulated in the quitter group. These expression patterns were consistent with mRNA and protein expression levels. We also found that the local Th2 cytokine expression and IgE class switching, as well as serum IgE levels, were elevated in the current smoker group and showed normal levels in the quitter group. Furthermore, the expressions of E-cadherin decreased while those of N-cadherin, α-SMA, and vimentin increased in the current smoker group compared those in the never smoker group. Taken together, these results indicate that TS contributes to the deterioration of pathogenesis by releasing local EDCs and Th2 cytokines, resulting in EMT in patients with CRSwNP. We verified that alterations of immunological response by TS in sinonasal epithelium can play a vital role in leading to CRSwNP.

• IMMUNE NETWORK
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• 제20권4호
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• pp.32.1-32.15
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• 2020

Influenza virus is the major cause of seasonal and pandemic flu. Currently, oseltamivir, a potent and selective inhibitor of neuraminidase of influenza A and B viruses, is the drug of choice for treating patients with influenza virus infection. However, recent emergence of oseltamivir-resistant influenza viruses has limited its efficacy. Morin hydrate (3,5,7,2',4'-pentahydroxyflavone) is a flavonoid isolated from Morus alba L. It has antioxidant, anti-inflammatory, neuroprotective, and anticancer effects partly by the inhibition of the NF-κB signaling pathway. However, its effects on influenza virus have not been studied. We evaluated the antiviral activity of morin hydrate against influenza A/Puerto Rico/8/1934 (A/PR/8; H1N1) and oseltamivir-resistant A/PR/8 influenza viruses in vitro. To determine its mode of action, we carried out time course experiments, and time of addition, hemolysis inhibition, and hemagglutination assays. The effects of the co-administration of morin hydrate and oseltamivir were assessed using the murine model of A/PR/8 infection. We found that morin hydrate reduced hemagglutination by A/PR/8 in vitro. It alleviated the symptoms of A/PR/8-infection, and reduced the levels of pro-inflammatory cytokines and chemokines, such as TNF-α and CCL2, in infected mice. Co-administration of morin hydrate and oseltamivir phosphate reduced the virus titers and attenuated pulmonary inflammation. Our results suggest that morin hydrate exhibits antiviral activity by inhibiting the entry of the virus.

• IMMUNE NETWORK
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• 제16권5호
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• pp.296-304
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• 2016

It has been reported that fatty acid binding proteins (FABPs) do not act only as intracellular mediators of lipid responses but also have extracellular functions. This study aimed to investigate whether extracellular liver type (L)-FABP has a biological activity and to determined serum L-FABP levels in patients with end-stage renal disease (ESRD). We isolated L-FABP complementary deoxyribonucleic acid (cDNA) from the Huh7 human hepatocarcinoma cell line and expressed the recombinant L-FABP protein in Escherichia coli. A549 lung carcinoma and THP-1 monocytic cells were stimulated with the human recombinant L-FABP. Human whole blood cells were also treated with the human recombinant L-FABP or interleukin (IL)-1α. IL-6 levels were measured in cell culture supernatants using IL-6 enzyme-linked immunosorbent assay (ELISA). Human recombinant L-FABP induced IL-6 in a dose-dependent manner in A549, THP-1 cells, and whole blood cells. The blood samples of healthy volunteers and patients with ESRD were taken after an overnight fast. The serum levels of L-FABP in healthy volunteers and ESRD patients were quantified with L-FABP ELISA. The values of L-FABP in patients with ESRD were significantly lower than those in the control group. Our results demonstrated the biological activity of L-FABP in human cells suggesting L-FABP can be a mediator of inflammation.

• IMMUNE NETWORK
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• 제20권5호
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• pp.41.1-41.11
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• 2020

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) is a positive-sense single-stranded RNA (+ssRNA) that causes coronavirus disease 2019 (COVID-19). The viral genome encodes twelve genes for viral replication and infection. The third open reading frame is the spike (S) gene that encodes for the spike glycoprotein interacting with specific cell surface receptor - angiotensin converting enzyme 2 (ACE2) - on the host cell membrane. Most recent studies identified a single point mutation in S gene. A single point mutation in S gene leading to an amino acid substitution at codon 614 from an aspartic acid 614 into glycine (D614G) resulted in greater infectivity compared to the wild type SARS-CoV2. We were interested in investigating the mutation region of S gene of SARS-CoV2 from Korean COVID-19 patients. New mutation sites were found in the critical receptor binding domain (RBD) of S gene, which is adjacent to the aforementioned D614G mutation residue. This specific sequence data demonstrated the active progression of SARS-CoV2 by mutations in the RBD of S gene. The sequence information of new mutations is critical to the development of recombinant SARS-CoV2 spike antigens, which may be required to improve and advance the strategy against a wide range of possible SARS-CoV2 mutations.

• IMMUNE NETWORK
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• 제24권3호
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• pp.15.1-15.18
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• 2024

Osteoarthritis (OA) involves cartilage degeneration, thereby causing inflammation and pain. Cardiovascular diseases, such as dyslipidemia, are risk factors for OA; however, the mechanism is unclear. We investigated the effect of dyslipidemia on the development of OA. Treatment of cartilage cells with low-density lipoprotein (LDL) enhanced abnormal autophagy but suppressed normal autophagy and reduced the activity of transcription factor EB (TFEB), which is important for the function of lysosomes. Treatment of LDL-exposed chondrocytes with rapamycin, which activates TFEB, restored normal autophagy. Also, LDL enhanced the inflammatory death of chondrocytes, an effect reversed by rapamycin. In an animal model of hyperlipidemia-associated OA, dyslipidemia accelerated the development of OA, an effect reversed by treatment with a statin, an anti-dyslipidemia drug, or rapamycin, which activates TFEB. Dyslipidemia reduced the autophagic flux and induced necroptosis in the cartilage tissue of patients with OA. The levels of triglycerides, LDL, and total cholesterol were increased in patients with OA compared to those without OA. The C-reactive protein level of patients with dyslipidemia was higher than that of those without dyslipidemia after total knee replacement arthroplasty. In conclusion, oxidized LDL, an important risk factor of dyslipidemia, inhibited the activity of TFEB and reduced the autophagic flux, thereby inducing necroptosis in chondrocytes.

• Tuberculosis and Respiratory Diseases
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• 제55권2호
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• pp.140-153
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• 2003

연구배경 : 결핵균 항원으로 세포 매개성 면역반응이 활성화되면 여러 종류의 cytokine이 분비되고 각기 다른 cytokine과 network system으로 작용하여 여러 병태생리적인 과정을 조절한다. 결핵 환자에서 염증반응, 조직파괴 및 질환의 중증도는 proinflammatory cytokine과 suppressive cytokine의 균형과 조합에 의하여 결정되며, 결핵 진행의 제한과 악화에 중요한 역할을 할 것으로 생각되고 있다. 따라서 결핵의 이환과정에서 cytokine의 분비 및 변화와 역할을 파악하는 것이 질환의 병태생리를 이해하는데 크게 도움이 될 수 있다. 대상 및 방법 : 활동성 폐결핵 83명, 기관지 결핵 10명의 치료전과 정상 대조군 20명에서 말초혈액을 채취하여 혈청을 분리하여 $-70^{\circ}C$에 보관하였고, sandwich ELISA 방법을 이용하여 혈청 IL-$1{\beta}$, IL-2, IL-4, IL-6, IL-10, IL-12(p40), TNF-${\alpha}$, IFN-${\gamma}$, TGF-${\beta}$를 측정하였다. 폐결핵 환자 83명을 ATS guideline에 따라 중증도를 분류하였고, 추적관찰 중 탈락자를 제외한 45명에서 초치료 2개월과 6개월 후 각각 혈청 sIL-$1{\beta}$, IL-2, IL-4, IL-6, IL-10, IL-12(p40), TNF-${\alpha}$, IFN-${\gamma}$, TGF-${\beta}$를 재측정하였다. 결 과 : 1) IL-$1{\beta}$, TNF-${\alpha}$, IFN-${\gamma}$는 폐결핵 환자에서 대조군에 비하여 증가된 경향을 보였고(p>0.05), IL-6는 폐결핵군에서 통계적으로 유의하게 증가되었다(p<0.05). TGF-${\beta}$는 폐결핵과 기관지 결핵환자에서의 분비가 대조군에 비하여 감소된 경향을 보였으며(p>0.05), IL-2, IL-12(p40), IL-4, IL-10은 대조군과 폐결핵 환자에서 별다른 차이를 보이지 않았다. 2) 기관지 결핵 환자에서 IL-6, TNF-${\alpha}$는 대조군에 비해 증가되고 TGF-${\beta}$는 감소된 경향을 보였다(p>0.05). 폐결핵에 비해 IL-12(p40)의 분비는 증가된 경향을 보였다. 3) 결핵의 중증도가 심할수록 IFN-${\gamma}$와 IL-6가 유의하게 증가하였고(P<0.05), 특히 중증군에서 현저하였다. 4) 폐결핵 환자에서 치료전 측정한 IL-$1{\beta}$, IL-6, TNF-${\alpha}$ 간 및 IL-2, IL-4, IL-12 간에는 강한 양의 상관관계를 보였다(p<0.01). 5) 폐결핵 환자 45명에서 측정한 IL-6와 IFN-${\gamma}$는 치료후 2개월과 6개월에 각각 통계적으로 유의하게 감소되었다(p<0.05). 결 론 : 이상의 결과로 결핵의 병태생리에 있어서 여러 cytokine간의 균형과 조합의 변화가 숙주의 염증, 조직파괴 및 결핵의 중증도와 관련되어 있을 것으로 생각되지만 결핵의 형태나 면역반응 정도에 따른 다양성을 보여서 결과의 해석과 cytokine 측정의 임상적 이용에 대한 연구가 더욱 필요할 것으로 사료된다.