• Korean Journal of Microbiology
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• v.49 no.3
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• pp.221-227
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• 2013

Human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) cause viral infections that lead to chronic diseases. When they invade human body, virus specific T cells play an important role in antiviral effector functions including killing virus-infected cells and helping B cells to produce specific antibodies against viral proteins. The antiviral activity of T cells is usually affected by immune-regulatory factors that express on surface of T cells. Recently, many researchers have investigated the relationship between effector functions of virus specific T cells and characteristics of immune regulatory factors (e.g., CD28, CD25, CD45RO, FoxP3, PD-1, CTLA-4). In particular, Immune inhibitory molecules such as forkhead box P3 (FoxP3), programmed death-1 (PD-1), and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) are associated with T-cell dysfunction. They are shown to be up-regulated in chronic viral diseases such as hepatitis B, hepatitis C or human immunodeficiency virus infection. Therefore, the positive correlation between viral persistence and expression of immune regulatory factors (FoxP3, PD-1, and CTLA-4) has been suggested. In this review, the roles of immune regulatory factors FoxP3, PD-1, and CTLA-4 were discussed in chronic viral diseases such as HIV, HBV, or HCV.

• Molecules and Cells
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• v.45 no.5
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• pp.317-328
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• 2022

Trophoblasts, important functional cells in the placenta, play a critical role in maintaining placental function. The heterogeneity of trophoblasts has been reported, but little is known about the trophoblast subtypes and distinctive functions during preeclampsia (PE). In this study, we aimed to gain insight into the cell type-specific transcriptomic changes by performing unbiased single-cell RNA sequencing (scRNA-seq) of placental tissue samples, including those of patients diagnosed with PE and matched healthy controls. A total of 29,006 cells were identified in 11 cell types, including trophoblasts and immune cells, and the functions of the trophoblast subtypes in the PE group and the control group were also analyzed. As an important trophoblast subtype, extravillous trophoblasts (EVTs) were further divided into 4 subgroups, and their functions were preliminarily analyzed. We found that some biological processes related to pregnancy, hormone secretion and immunity changed in the PE group. We also identified and analyzed the regulatory network of transcription factors (TFs) identified in the EVTs, among which 3 modules were decreased in the PE group. Then, through in vitro cell experiments, we found that in one of the modules, CEBPB and GTF2B may be involved in EVT dysfunction in PE. In conclusion, our study showed the different transcriptional profiles and regulatory modules in trophoblasts between placentas in the control and PE groups at the single-cell level; these changes may be involved in the pathological process of PE, providing a new molecular theoretical basis for preeclamptic trophoblast dysfunction.

• Journal of Animal Reproduction and Biotechnology
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• v.37 no.3
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• pp.169-175
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• 2022

Bovine mammary epithelial (MAC-T) cells are commonly used to study mammary gland development and mastitis. Lipopolysaccharide is a major bacterial cell membrane component that can induce inflammation. Autophagy is an important regulatory mechanism participating in the elimination of invading pathogens. In this study, we evaluated the mechanism underlying bacterial mastitis and mammary cell death following lipopolysaccharide treatment. After 24 h of 50 ㎍/mL lipopolysaccharide treatment, a significant decrease in the proliferation rate of MAC-T cells was observed. However, no changes were observed upon treatment of MAC-T cells with 10 ㎍/mL of lipopolysaccharide for up to 48 h. Thus, upon lipopolysaccharide treatment, MAC-T cells exhibit dose-dependent effects of growth inhibition at 10 ㎍/mL and death at 50 ㎍/mL. Treatment of MAC-T cells with 50 ㎍/mL lipopolysaccharide also induced the expression of autophagy-related genes ATG3, ATG5, ATG10, ATG12, MAP1LC3B, GABARAP-L2, and BECN1. The autophagy-related LC3A/B protein was also expressed in a dose-dependent manner upon lipopolysaccharide treatment. Based on these results, we suggest that a high dose of bacterial infection induces mammary epithelial cell death related to autophagy signals.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.3
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• pp.428-436
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• 2003

Epidemiological studies have observed a negative association between increased consumption of green and yellow vegetables and cancer incidence. These vegetables contain carotenoids, which are reported to exhibit anticarcinogenic effects. Overexpression of ErbB2 and ErbB3 genes is a frequent event in several human cancers. The present study was performed to determine whether $\alpha$-carotene, $\beta$-carotene, lutein, or lycopene inhibits cell growth and to assess such an effect is related to changes in the levels of the ErbB receptor family and tile ErbB3 receptor signaling pathway in HT-29 cells. HT-29 cells were cultured in serum-free medium in the presence of various concentrations (0~100 $\mu$M) of the individual carotenoids. $\alpha$ -Carotene and lycopene significantly inhibited cell growth in a dose-dependent manner, whereas lutein slightly inhibited cell growth and $\beta$-carotene increased cell growth. Lycopene is more potent than $\alpha$ -carotene in inhibiting HT-29 cell growth. Lycopene inhibited DNA synthesis and induced apoptosis of HT-29 cells. The ErbB3 ligand heregulin (HRG) increased cell growth but did not prevent the lycopene-induced inhibition of cell growth. Lycopene decreased ErbB2 protein levels in a dose-dependent manner. Immunoprecipitation/Western blot studies revealed that lycopene inhibited HRG-induced phosphorylation of ErbB3, recruitment of the 985 regulatory subunit of phosphatidylinositol 3-kinase (PI3K) to the ErbB3 receptor, and phosphorylation of Akt. These results indicate that downregulation of ErbB2/ErbB3/PI3K/Akt signaling may be one of the mechanisms by which lycopene inhibits HT-29 cell pro-liferation and induces apoptosis.

• BMB Reports
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• v.48 no.3
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• pp.172-177
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• 2015

Upregulation of pro-inflammatory mediators contributes to ${\beta}$-cell destruction and enhanced infiltration of immune cells into pancreatic islets during development of type 1 diabetes mellitus. In this study, we examined the regulatory effects and the mechanisms of action of celastrol against cytotoxicity and pro-inflammatory immune responses in the RINm5F rat pancreatic ${\beta}$-cell line stimulated with a combination of interleukin-1 beta, tumor necrosis factor-alpha, and interferon-${\gamma}$. Celastrol significantly restored cytokine-induced cell death and significantly inhibited cytokine-induced nitric oxide production. In addition, the protective effect of celastrol was correlated with a reduction in pro-inflammatory mediators, such as inducible nitric oxide synthase, cyclooxygenase-2, and CC chemokine ligand 2. Furthermore, celastrol significantly suppressed cytokine-induced signaling cascades leading to nuclear factor kappa B (NF-${\kappa}B$) activation, including $I{\kappa}B$-kinase (IKK) activation, $I{\kappa}B$ degradation, p65 phosphorylation, and p65 DNA binding activity. These results suggest that celastrol may exert its cytoprotective activity by suppressing cytokine-induced expression of pro-inflammatory mediators by inhibiting activation of NF-${\kappa}B$ in RINm5F cells.

• YAKHAK HOEJI
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• v.52 no.5
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• pp.412-417
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• 2008

BAY11-7082 was initially found to be an anti-inflammatory drug with NF-${\kappa}B$ inhibitory property. In this study, we evaluated modulatory function of BAY11-7082 on U937 cell-cell adhesion induced by CD29 (${\beta}1$-integrins). BAY11-7082 strongly blocked functional activation of CD29 (${\beta}1$-integrins), as assessed by cell-cell adhesion assay. However, this compound did not block a simple activation of CD29, as assessed by cell-fibronectin adhesion assay. In particular, to understand molecular mechanism of BAY11-7082-mediated inhibition, the regulatory roles of CD29-induced actin cytoskeleton rearrangement under cell-cell adhesion and surface level of CD29 were examined using confocal and flow cytometic analysis. Interestingly, this compound strongly suppressed the molecular association of actin cytoskeleton with CD29 at cell-cell adhesion site. Moreover, BAY11-7082 also diminished surface levels of CD29 as well as its-associated adhesion molecule CD147, but not other adhesion molecules such as CD18 and CD43. Therefore, our data suggest that BAY11-7082 may be involved in regulating immune responses managed by CD29-mediated cell-cell adhesion.

• Korean Journal of Plant Resources
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• v.33 no.6
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• pp.659-665
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• 2020

Adenophorae Radix (AR) has been used as a traditional medicine for various diseases. However, the regulatory mechanisms of AR in allergic inflammation are not yet understood. The present study was conducted to investigate the effect and mechanisms of AR on the mast cell-mediated allergic response. To determine the pharmacological mechanisms of AR in allergic inflammation, we evaluated the effects of AR on the production of tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1β and IL-8 as well as the activation of nuclear factor-κB (NF-κB) and caspase-1 in phorbol 12-myristate 13-acetate plus calcium ionophore A23187 (PMACI)-stimulated human mast cells (HMC-1). Our results demonstrated that AR effectively attenuated the PMACI-induced production of TNF-α, IL-6, IL-1β and IL-8 in stimulated HMC-1. Additionally, we showed that the inhibitory effect of AR on inflammatory cytokines in PMACI-stimulated HMC-1 cells involved the suppression of the activation NF-kB/caspase-1 in PMACI-stimulated HMC-1. Collectively, these findings provide experimental evidence that AR may be a useful candidate for the treatment of allergic inflammation.

• Biomedical Science Letters
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• v.29 no.3
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• pp.137-143
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• 2023

Inflammation plays an important role in immune system's response to tissue injury and biological stimuli. However, excessive inflammation can cause tissue damage. Therefore, the development of naturally derived anti-inflammatory agents have received broad attention. In this study, we investigated the anti-inflammatory mechanism of Rubi Fructus (RF) extract on the mast cell-mediated inflammatory response. To determine the regulatory mechanism of RF in inflammatory reaction, we evaluated the effects of RF on secretion of interleukin (IL)-8, IL-6 and tumor necrosis factor (TNF)-α and activation of nuclear factor-κB (NF-κB) and caspase-1 in activated human mast cells-1 (HMC-1). The results showed that RF attenuated IL-8, IL-6 and TNF-α secretion in a concentration-dependent manner. Moreover, RF significantly attenuated caspase-1and NF-κB activation in activated HMC-1. Conclusively, the present results provide evidence that RF may be a promising agent for anti-inflammatory therapy.

• BMB Reports
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• v.49 no.5
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• pp.293-296
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• 2016

The immunoregulatory cytokine Interleukin 10 (IL-10) protein is produced by various cells during the course of inflammatory disorders. Mainly, it downregulates pro-inflammatory cytokines, antigen presentation, and helper T cell activation. In this study, we show that the ratio of IL-10-producing cells was significantly increased in lineage negative (i.e., not T, B, or leukocyte cell lineages) cells than in lineage positive cells in lymphoid and peripheral tissues. We further observed that IL-10-producing innate lymphoid cells (ILCs), here called firstly ILC10, were increased in number in oxazolone-induced contact hypersensitivity (CHS) mice. In detail, IL-10-producing lineage negative cells were elevated in the axillary, inguinal lymph node, and ear tissues of CHS mice. Notably, the cells expressed classical ILC marker proteins such as CD45, CD127, and Sca-1. Altogether, our findings suggest for the first time that ILC10s are present in various physiological settings and could be involved in numerous immune responses as regulatory cells.

• Molecules and Cells
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• v.44 no.5
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• pp.342-355
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• 2021

The microphthalmia-associated transcription factor family (MiT family) proteins are evolutionarily conserved transcription factors that perform many essential biological functions. In mammals, the MiT family consists of MITF (microphthalmia-associated transcription factor or melanocyte-inducing transcription factor), TFEB (transcription factor EB), TFE3 (transcription factor E3), and TFEC (transcription factor EC). These transcriptional factors belong to the basic helix-loop-helix-leucine zipper (bHLH-LZ) transcription factor family and bind the E-box DNA motifs in the promoter regions of target genes to enhance transcription. The best studied functions of MiT proteins include lysosome biogenesis and autophagy induction. In addition, they modulate cellular metabolism, mitochondria dynamics, and various stress responses. The control of nuclear localization via phosphorylation and dephosphorylation serves as the primary regulatory mechanism for MiT family proteins, and several kinases and phosphatases have been identified to directly determine the transcriptional activities of MiT proteins. In different immune cell types, each MiT family member is shown to play distinct or redundant roles and we expect that there is far more to learn about their functions and regulatory mechanisms in host defense and inflammatory responses.