• BMB Reports
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• v.49 no.10
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• pp.529-535
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• 2016

The NLRP3 inflammasome is activated by a variety of external or host-derived stimuli and its activation initiates an inflammatory response through caspase-1 activation, resulting in inflammatory cytokine IL-1β maturation and secretion. The NLRP3 inflammasome activation is a kind of innate immune response, most likely mediated by myeloid cells acting as a host defense mechanism. However, if this activation is not properly regulated, excessive inflammation induced by overactivated NLRP3 inflammasome can be detrimental to the host, causing tissue damage and organ dysfunction, eventually causing several diseases. Previous studies have suggested that mitochondrial damage may be a cause of NLRP3 inflammasome activation and autophagy, which is a conserved self-degradation process that negatively regulates NLRP3 inflammasome activation. Recently, mitochondria-selective autophagy, termed mitophagy, has emerged as a central player for maintaining mitochondrial homeostasis through the elimination of damaged mitochondria, leading to the prevention of hyperinflammation triggered by NLRP3 inflammasome activation. In this review, we will first focus on the molecular mechanisms of NLRP3 inflammasome activation and NLRP3 inflammasome-related diseases. We will then discuss autophagy, especially mitophagy, as a negative regulator of NLPP3 inflammasome activation by examining recent advances in research.

• Molecules and Cells
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• v.43 no.11
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• pp.964-973
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• 2020

Recent studies have highlighted that early enhancement of the glycolytic pathway is a mode of maintaining the proinflammatory status of immune cells. Thiamine, a wellknown co-activator of pyruvate dehydrogenase complex, a gatekeeping enzyme, shifts energy utilization of glucose from glycolysis to oxidative phosphorylation. Thus, we hypothesized that thiamine may modulate inflammation by alleviating metabolic shifts during immune cell activation. First, using allithiamine, which showed the most potent anti-inflammatory capacity among thiamine derivatives, we confirmed the inhibitory effects of allithiamine on the lipopolysaccharide (LPS)-induced pro-inflammatory cytokine production and maturation process in dendritic cells. We applied the LPS-induced sepsis model to examine whether allithiamine has a protective role in hyper-inflammatory status. We observed that allithiamine attenuated tissue damage and organ dysfunction during endotoxemia, even when the treatment was given after the early cytokine release. We assessed the changes in glucose metabolites during LPS-induced dendritic cell activation and found that allithiamine significantly inhibited glucose-driven citrate accumulation. We then examined the clinical implication of regulating metabolites during sepsis by performing a tail bleeding assay upon allithiamine treatment, which expands its capacity to hamper the coagulation process. Finally, we confirmed that the role of allithiamine in metabolic regulation is critical in exerting anti-inflammatory action by demonstrating its inhibitory effect upon mitochondrial citrate transporter activity. In conclusion, thiamine could be used as an alternative approach for controlling the immune response in patients with sepsis.

• The Journal of Internal Korean Medicine
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• v.28 no.4
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• pp.681-693
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• 2007

Background and Objective : Atractylodes japonica (AJ) is a commonly-used herbal medicine in Asian countries such as Korea, China and Japan. The present study was designated to evaluate the direct effects of AJ on helper T cell activities and on Th1/Th2 lineage development in vitro. Materials and Methods : Spleen cells from 8-week BALB/c mice were cultured in CR extracts containing medium without activation for 24 hours and with activation for 48 hours. CD4+ T cells were isolated and analyzed for mRNA expression levels of INF-$\gamma$, IL-4, T-bet and GATA-3 by RT-PCR and secretion cytokines levels of INF-$\gamma$, IL-2, IL-4, IL-5 and IL-10 by ELISA. Results : The results demonstrated that AJ had no mitogenic effects on unstimulated CD4+ T cells, but augmented CD4+T-cell proliferation upon activation with anti-CD3/anti-CD28 antibodies in a dose-dependent manner. AJ treatment significantly increased CD4+ T cell population and IFN-$\gamma$ expression was significantly enhanced, while IL-4 expression significantly decreased. In addition, in vitro Th1/Th2 polarization experiments revealed that AJ enhanced IFN-$\gamma$ secretion in Th1 cells, but reduced the IL-4 in Th2 cells in dose-dependent manner. Conclusion : These results suggest that AJ treatment could be a desirable alternative therapy for the prevention or correction of Th2 dominant pathological disorders, such as allergy and asthma.

• Journal of Microbiology and Biotechnology
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• v.25 no.2
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• pp.255-267
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• 2015

Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of Johne's disease, a chronic debilitating disease affecting ruminants worldwide. In the present study, we aimed to determine the major gene networks and pathways underlying the immune response to MAP infection using whole-blood cells, as well as provide the potential transcriptional markers for identifying the status of MAP infection. We analyzed the transcriptional profiles of whole-blood cells of cattle identified and grouped according to the presence of MAP-specific antibodies and the MAP shed by them. The grouping was based on the results obtained by ELISA and PCR analyses as follows: i) Test1 group: MAP-negative results obtained by ELISA and positive results obtained by PCR; ii) Test2 group: MAP-positive results obtained by ELISA and negative results obtained by PCR; iii) Test3 group: MAP-positive results obtained by ELISA and positive results obtained by PCR; iv) uninfected control: MAP-negative results obtained both by ELISA and PCR analysis. The results showed down-regulated production and metabolism of reactive oxygen species in the Test1 group, activation of pathways related to the host-defense response against MAP (LXR/RXR activation and complement system) in the Test2 and Test3 groups, and anti-inflammatory response (activation of IL-10 signaling pathway) only in the Test3 group. Our data indicate a balanced response that serves the immune-limiting mechanism while the host-defense responses are progressing.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.1
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• pp.150-155
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• 1994

In order to evaluate the effect of the extracts of eidble and medicinalplant son the activation of immune cells, measurements were made by ELISA and radioimmunoassay on the degree of release for the tumor necrosis factor (TNF) and neopterin by the edible and medicinal plants in peripheral blood cells. The results of measurements of TNF in the supernatant cultured liquid showed nothing in t도 control which does not have any edible and medicinal plants. However, measurements of TNF 9pg/ml) in the samples are given as follows : 716.7 in lipopolysaccharide (LPS 1 g/ml), 465.2 Rheum plamatum L.m302.7 Sanguisorba offciinalis L. 818.2 Rubus coreanus M, 328.3 Terminalia chebula R., 426.6 AReca catechu L. 227.0 Eugenia caryophiliata T., 272.9 Ephedra sinica S., 30.1 Caesalpinia sappan L., 474.0 Chaenomeles japonica L., 396.0 Cornus officinalis S.in edible and medicinalplants. ENopterin (n mole/L) value showed below the check point in the control group, however, the values are 11.0 in LPS, and edible and medicinal plants, 5.3 Rheum palmatum L., 11.6 Eugenia caryophiliata T., 5.5 Ephedra sinica S., 4.5 Caesalpinia sappan L., 4.3 Chaenomelees japonica L.3.7 Cornus officinalis S. In order to find m RNA levels of Cytokines increased by edible and medicinal plants, total RNA was separated from mononuclear cells treated 5 hrs with Rubus coreanus M. and then administrated for RT-PCR. The considerable increases of the m RNA of TNF, IL-1 $\alpha$ and IL-6 were observed.

• Biomolecules & Therapeutics
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• v.2 no.4
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• pp.376-382
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• 1994

Repeated injections of low-doses of mercuric chloride in rats or mice induce polyclonal activation which includes the induction of anti-glomerular basement membrane (GBM) antibodies and circulating immune complex and it results in nephritis. Because this disease is autoimmune mediated disease resulted from immune dysfunction, immunomodulators are used to control the symptoms or to cure the disease. Irpex lacteus Fr. is a kind of new medicinal fungus. The polysaccharide fraction extracted from submerged fermentation of Irpex lacteus Fr. decreased the serum agglutinin, serolysin and IgM plaque forming cells in normal mice. The hitherto obtained clinical results suggested that it significantly improved the oligourea, edema, and hypertension in patients who have nephritis. To elucidate the action-mechanisms of Irpex lacteus Fr., we established the experimental model of HgCl$_2$induced polyclonal activation by intraperitoneal administrations of HgCl$_2$to mice. To assess the immunomodulating effect of Irpex lacteus fraction, we Investigated its effects on the mitogen induced proliferation and IgM PFC counts of splenic lymphocytes in mice during the treatment of HgCl$_2$. The Irpex lacteus polysaccharide reduced the abnormally increased mitogen induced Iymphocyte proliferation and IgM PFCs to almost normal levels. And the Irpex lacteus polysaccharides prevented the increasement of serum immunoglobulin level induced by HgCl$_2$. These data suggested that the Irpex lacteus polysaccharides might have the immunomodulating activity to prevent and /or improve the HgCl$_2$ induced autoimmune disease.

• BMB Reports
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• v.52 no.10
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• pp.613-618
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• 2019

Microglial cells are known as the main immune cells in the central nervous system, both regulating its immune response and maintaining its homeostasis. Furthermore, the antioxidant ${\alpha}-lipoic$ acid (LA) is a recognized therapeutic drug for diabetes because it can easily invade the blood-brain barrier. This study investigated the effect of ${\alpha}-LA$ on the inflammatory response in lipopolysaccharide (LPS)-treated BV-2 microglial cells. Our results revealed that ${\alpha}-LA$ significantly attenuated several inflammatory responses in BV-2 microglial cells, including pro-inflammatory cytokines, such as tumor necrosis $factor-{\alpha}$ and interleukin (IL)-6, and other cytotoxic molecules, such as nitric oxide and reactive oxygen species. In addition, ${\alpha}-LA$ inhibited the LPS-induced phosphorylation of ERK and p38 and its pharmacological properties were facilitated via the inhibition of the nuclear factor kappa B signaling pathway. Moreover, ${\alpha}-LA$ suppressed the activation of NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasomes, multiprotein complexes consisting of NLRP3 and caspase-1, which are involved in the innate immune response. Finally, ${\alpha}-LA$ decreased the genes accountable for the M1 phenotype, $IL-1{\beta}$ and ICAM1, whereas it increased the genes responsible for the M2 phenotype, MRC1 and ARG1. These findings suggest that ${\alpha}-LA$ alleviates the neuroinflammatory response by regulating microglial polarization.

• IMMUNE NETWORK
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• v.23 no.3
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• pp.22.1-22.15
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• 2023

Alcoholic liver cirrhosis (ALC) is caused by chronic alcohol overconsumption and might be linked to dysregulated immune responses in the gut-liver axis. However, there is a lack of comprehensive research on levels and functions of innate lymphocytes including mucosal-associated invariant T (MAIT) cells, NKT cells, and NK (NK) cells in ALC patients. Thus, the aim of this study was to examine the levels and function of these cells, evaluate their clinical relevance, and explore their immunologic roles in the pathogenesis of ALC. Peripheral blood samples from ALC patients (n = 31) and healthy controls (HCs, n = 31) were collected. MAIT cells, NKT cells, NK cells, cytokines, CD69, PD-1, and lymphocyte-activation gene 3 (LAG-3) levels were measured by flow cytometry. Percentages and numbers of circulating MAIT cells, NKT cells, and NK cells were significantly reduced in ALC patients than in HCs. MAIT cell exhibited increased production of IL-17 and expression levels of CD69, PD-1, and LAG-3. NKT cells displayed decreased production of IFN-γ and IL-4. NK cells showed elevated CD69 expression. Absolute MAIT cell levels were positively correlated with lymphocyte count but negatively correlated with C-reactive protein. In addition, NKT cell levels were negatively correlated with hemoglobin levels. Furthermore, log-transformed absolute MAIT cell levels were negatively correlated with the Age, Bilirubin, INR, and Creatinine score. This study demonstrates that circulating MAIT cells, NKT cells, and NK cells are numerically deficient in ALC patients, and the degree of cytokine production and activation status also changed. Besides, some of their deficiencies are related to several clinical parameters. These findings provide important information about immune responses of ALC patients.

• IMMUNE NETWORK
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• v.21 no.6
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• pp.42.1-42.20
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• 2021

Eosinophils play critical roles in the maintenance of homeostasis in innate and adaptive immunity. Although primarily known for their roles in parasitic infections and the development of Th2 cell responses, eosinophils also play complex roles in other immune responses ranging from anti-inflammation to defense against viral and bacterial infections. However, the contributions of pattern recognition receptors in general, and NOD-like receptors (NLRs) in particular, to eosinophil involvement in these immune responses remain relatively underappreciated. Our in vivo studies demonstrated that NLRC4 deficient mice had a decreased number of eosinophils and impaired Th2 responses after induction of an allergic airway disease model. Our in vitro data, utilizing human eosinophilic EoL-1 cells, suggested that TLR2 induction markedly induced pro-inflammatory responses and inflammasome forming NLRC4 and NLRP3. Moreover, activation by their specific ligands resulted in caspase-1 cleavage and mature IL-1β secretion. Interestingly, Th2 responses such as secretion of IL-5 and IL-13 decreased after transfection of EoL-1 cells with short interfering RNAs targeting human NLRC4. Specific induction of NLRC4 with PAM3CSK4 and flagellin upregulated the expression of IL-5 receptor and expression of Fc epsilon receptors (FcεR1α, FcεR2). Strikingly, activation of the NLRC4 inflammasome also promoted expression of the costimulatory receptor CD80 as well as expression of immunoregulatory receptors PD-L1 and Siglec-8. Concomitant with NLRC4 upregulation, we found an increase in expression and activation of matrix metalloproteinase (MMP)-9, but not MMP-2. Collectively, our results present new potential roles of NLRC4 in mediating a variety of eosinopilic functions.

• IMMUNE NETWORK
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• v.14 no.1
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• pp.14-20
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• 2014

CD28/T cell receptor ligation activates the NF-${\kappa}B$ signaling cascade during CD4 T cell activation. NF-${\kappa}B$ activation is required for cytokine gene expression and activated T cell survival and proliferation. Recently, many reports showed that NF-${\kappa}B$ activation is also involved in T helper (Th) cell differentiation including Th17 cell differentiation. In this review, we discuss the current literature on NF-${\kappa}B$ activation pathway and its effect on Th17 cell differentiation.