• Title/Summary/Keyword: Immune Functions

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Regulation of Inflammation by Bidirectional Signaling through CD137 and Its Ligand

  • Kwon, Byungsuk
    • IMMUNE NETWORK
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    • v.12 no.5
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    • pp.176-180
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    • 2012
  • Although the majority of research on CD137 has been directed to T cells, it is becoming clear that this molecule has distinct functions in other lineages of cells, including non-hematopoietic cells. In particular, emerging evidence suggests that the CD137-its ligand (CD137L) network involving immune cells and non-immune cells, directly or indirectly regulates inflammation in both positive and negative manners. Bidirectional signaling through both CD137 and CD137L is critical in the evolution of inflammation: 1) CD137L signaling plays an indispensible role in the activation and recruitment of neutrophils by inducing the production of proinflammatory cytokines and chemokines in hematopoietic and non-hematopoietic cells such as macrophages, endothelial cells and epithelial cells; 2) CD137 signaling in NK cells and T cells is required for their activation and can influence other cells participating in inflammation via either their production of proinflammatory cytokines or engagement of CD137L by their cell surface CD137: 3) CD137 signaling can suppress inflammation by controlling regulatory activities of dendritic cells and regulatory T cells. As recognition grows of the role of dysregulated CD137 or CD137L stimulation in inflammatory diseases, significant efforts will be needed to develop antagonists to CD137 or CD137L.

Effect of Gyogamdan Administration on the Stress-Induced Immunosuppression in the Mouse (교감단(交感丹)의 투여가 STRESS에 의한 면역반응의 억제에 미치는 영향)

  • Hwang Hyun-Soon;Lyu Young-Su
    • Journal of Oriental Neuropsychiatry
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    • v.8 no.2
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    • pp.13-24
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    • 1997
  • This study was done to know the effects of the water extracts of Gyogamdan(GGD) on the function of macrophages, the most important cells of the innate immune system, and the rosette forming ability of splenocytes in the mouse under stress. The effects of GGD on the immunosuppression induced by noise stress are as follows. 1. Administration of GGD water extracts normalized the bo요 weight which might be decreased by noise stress. 2. Administration of GGD water extracts increased the production of the such reactive oxygen intermediates as superoxide and hydrogen peroxide from macrophsges in vivo & in vitro which were decreased by noise stress. 3. Administration of GGS water extracts did not affect the production of reactive nitrogen intermediates. 4. Administration of GGD water extracts increased the rosette forming ability of splenocytes which was decreased by noise stress. The above effects of GGD might be useful for the treatment of stress-induced infections diseases which could be caused by the suppression of immune responeses which are initiated by the functions of macrophages of the innate immune system.

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Modulation of TNFSF expression in lymphoid tissue inducer cells by dendritic cells activated with Toll-like receptor ligands

  • Han, Sin-Suk;Koo, Ji-Hye;Bae, Jin-Gyu;Kim, Soo-Chan;Baik, Song;Kim, Mi-Yeon
    • BMB Reports
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    • v.44 no.2
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    • pp.129-134
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    • 2011
  • Toll-like receptors (TLRs), which recognize structurally conserved components among pathogens, are mainly expressed by antigen-presenting cells such as dendritic cells (DCs), B cells, and macrophages. Recognition through TLRs triggers innate immune responses and influences antigen-specific adaptive immune responses. Although studies on the expression and functions of TLRs in antigen-presenting cells have been extensively reported, studies in lymphoid tissue inducer (LTi) cells have been limited. In this study, we observed that LTi cells expressed TLR2 and TLR4 mRNA as well as TLR2 protein and upregulated OX40L, CD30L, and TRANCE expression after stimulation with the TLR2 ligand zymosan or TLR4 ligand LPS. The expression of tumor necrosis factor superfamily (TNFSF) members was significantly upregulated when cells were cocultured with DCs, suggesting that upregulated TNFSF expression may contribute to antigen-specific adaptive immune responses.

Exploration of Molecular Mechanisms of Diffuse Large B-cell Lymphoma Development Using a Microarray

  • Zhang, Zong-Xin;Shen, Cui-Fen;Zou, Wei-Hua;Shou, Li-Hong;Zhang, Hui-Ying;Jin, Wen-Jun
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.3
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    • pp.1731-1735
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    • 2013
  • Objective: We aimed to identify key genes, pathways and function modules in the development of diffuse large B-cell lymphoma (DLBCL) with microarray data and interaction network analysis. Methods: Microarray data sets for 7 DLBCL samples and 7 normal controls was downloaded from the Gene Expression Omnibus (GEO) database and differentially expressed genes (DEGs) were identified with Student's t-test. KEGG functional enrichment analysis was performed to uncover their biological functions. Three global networks were established for immune system, signaling molecules and interactions and cancer genes. The DEGs were compared with the networks to observe their distributions and determine important key genes, pathways and modules. Results: A total of 945 DEGs were obtained, 272 up-regulated and 673 down-regulated. KEGG analysis revealed that two groups of pathways were significantly enriched: immune function and signaling molecules and interactions. Following interaction network analysis further confirmed the association of DEGs in immune system, signaling molecules and interactions and cancer genes. Conclusions: Our study could systemically characterize gene expression changes in DLBCL with microarray technology. A range of key genes, pathways and function modules were revealed. Utility in diagnosis and treatment may be expected with further focused research.

HVEM is a TNF Receptor with Multiple Regulatory Roles in the Mucosal Immune System

  • Shui, Jr-Wen;Kronenberg, Mitchell
    • IMMUNE NETWORK
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    • v.14 no.2
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    • pp.67-72
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    • 2014
  • The herpes virus entry mediator (HVEM) is a member of the tumor necrosis factor receptor superfamily (TNFRSF), and therefore it is also known as TNFRSF14 or CD270 (1,2). In recent years, we have focused on understanding HVEM function in the mucosa of the intestine, particularly on the role of HVEM in colitis pathogenesis, host defense and regulation of the microbiota (2-4). HVEM is an unusual TNF receptor because of its high expression levels in the gut epithelium, its capacity to bind ligands that are not members of the TNF super family, including immunoglobulin (Ig) superfamily members BTLA and CD160, and its bi-directional functionality, acting as a signaling receptor or as a ligand for the receptor BTLA. Clinically, Hvem recently was reported as an inflammatory bowel disease (IBD) risk gene as a result of genome wide association studies (5,6). This suggests HVEM could have a regulatory role influencing the regulation of epithelial barrier, host defense and the microbiota. Consistent with this, using mouse models, we have revealed how HVEM is involved in colitis pathogenesis, mucosal host defense and epithelial immunity (3,7). Although further studies are needed, our results provide the fundamental basis for understanding why Hvem is an IBD risk gene, and they confirm that HVEM is a mucosal gatekeeper with multiple regulatory functions in the mucosa.

Characterization and expression profiles of aquaporins (AQPs) 1a and 3a in mud loach Misgurnus mizolepis after experimental challenges

  • Lee, Sang Yoon;Nam, Yoon Kwon;Kim, Yi Kyung
    • Fisheries and Aquatic Sciences
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    • v.20 no.9
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    • pp.23.1-23.9
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    • 2017
  • Two distinct cDNAs encoding aquaporins (mmAQPs 1a and 3a) were isolated and characterized from mud loach Misgurnus mizolepis. The identified mud loach AQP cDNAs encode for polypeptides of 260 and 302 amino acids. Topology predictions confirmed six putative membrane-spanning domains connected by five loops and the N- and C-terminal domains being cytoplasmic. The mud loach AQPs 1a and 3a showed broad distribution in multiple tissues including immune-responsive tissues as well as osmoregulatory tissues. Hence, the diversity of AQP distribution and expression possibly indicated its differential functions in the regulation of fluid movement in response to environmental stimuli. The transcription of mmAQP genes was differentially modulated by immune challenges. In particular, the mmAQP3a expression level in the liver was more responsive to immune challenges than that of mmAQP1a. Taken together, fish stimulation or infection resulted in significant modulation of mud loach AQP genes, suggesting potential functional roles of these proteins in piscine pathophysiological process.

Acute Immunotoxic Effects of Chlorpyrifos in CBA Male Mice (유기인계 Chlorpyrifos가 생쥐에 미치는 급성 면역 독성)

  • 김강석
    • Environmental Analysis Health and Toxicology
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    • v.13 no.1_2
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    • pp.33-41
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    • 1998
  • Chlorpyrifos, o,o diethyl-o-(3,5,6-trichloro-2-pyridyl) phosphorothioate, is a broad spectrum organophosphate insecticide. The use of chlorpyrifos has been increased more and more as pesticide. But the effects of chlorpyrifos on the immune alterations has not been yet observed. Therefore, we investigated the effects of chlorpyrifos on the immune alterations in CICA male mice. Chlorpyrifos was administered to mice by a single intraperitoneal injection for the purpose of observing acute effects. On the one hand to get the information on immunopathologic alterations we observed hematological values, counted total circulating leukocytes and assessed the ratio of lymphocytes and neutrophils from the peripheral blood, measured the ratio of organ/body weight and counted splenic cellularity in CBA male mice which treated chlorpyrifos intraperitoneally. But we could not find any significant immunopathologic alterations statistically by a single intraperitoneal injection. Also, the exposure of chlorpyrifos caused no significant change in the number of PFC/10$^6$ spleen cells at any three given doses. On the other hand a singte intraperitoneal injection of chlorpyrifos decreased the lymphocyte proliferation response slightly to ConA or LPS stimulation at a dose of 6 mg/kg b.w. Administrations of chlorpyrifos reduced mixed leukocyte response(MLR). MLR was decreased moderately at doses of 3mg/kg b.w. and 6mg/kg b.w. Therefore, all these findings suggest that chlorpyrifos may alter the immune functions acutely. especially by the changes of T lymphocyte activity.

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Comparative analysis of dietary exosome-derived microRNAs from human, bovine and caprine colostrum and mature milk

  • Yun, Bohyun;Kim, Younghoon;Park, Dong June;Oh, Sangnam
    • Journal of Animal Science and Technology
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    • v.63 no.3
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    • pp.593-602
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    • 2021
  • Mammalian milk including microRNAs (miRNAs) as a novel class of noncoding RNAs, that can be transferred to infants and it plays on a critical role in biological functions such as immune regulation and development. However, the origin and functional importance of milk-derived miRNAs are still undetermined. This study applied RNA sequencing to explore the featured profiles of miRNA expression in colostrum and mature milk-originated exosomes from human, bovine, and caprine milk. These dietary exosome-derived miRNAs are highly conserved in human, bovine and caprine milk. Interestingly, abundant miRNAs expressed in human milk are similarly conserved across species. In addition, we confirmed that immune-related miRNAs (miR-30a-5p, miR-22-3p, and miR-26a) are commonly observed in the colostrum and mature milk of cows and caprines as well as humans. Our results provide new insights and resources for investigating the functionality of immune-associated miRNAs and evaluating physiological and biological condition in human, bovine and caprine milk as biomarkers.

Anti-Inflammatory Role of TAM Family of Receptor Tyrosine Kinases Via Modulating Macrophage Function

  • Lee, Chang-Hee;Chun, Taehoon
    • Molecules and Cells
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    • v.42 no.1
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    • pp.1-7
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    • 2019
  • Macrophage is an important innate immune cell that not only initiates inflammatory responses, but also functions in tissue repair and anti-inflammatory responses. Regulating macrophage activity is thus critical to maintain immune homeostasis. Tyro3, Axl, and Mer are integral membrane proteins that constitute TAM family of receptor tyrosine kinases (RTKs). Growing evidence indicates that TAM family receptors play an important role in anti-inflammatory responses through modulating the function of macrophages. First, macrophages can recognize apoptotic bodies through interaction between TAM family receptors expressed on macrophages and their ligands attached to apoptotic bodies. Without TAM signaling, macrophages cannot clear up apoptotic cells, leading to broad inflammation due to over-activation of immune cells. Second, TAM signaling can prevent chronic activation of macrophages by attenuating inflammatory pathways through particular pattern recognition receptors and cytokine receptors. Third, TAM signaling can induce autophagy which is an important mechanism to inhibit NLRP3 inflammasome activation in macrophages. Fourth, TAM signaling can inhibit polarization of M1 macrophages. In this review, we will focus on mechanisms involved in how TAM family of RTKs can modulate function of macrophage associated with anti-inflammatory responses described above. We will also discuss several human diseases related to TAM signaling and potential therapeutic strategies of targeting TAM signaling.

Emerging role of bystander T cell activation in autoimmune diseases

  • Shim, Chae-Hyeon;Cho, Sookyung;Shin, Young-Mi;Choi, Je-Min
    • BMB Reports
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    • v.55 no.2
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    • pp.57-64
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    • 2022
  • Autoimmune disease is known to be caused by unregulated self-antigen-specific T cells, causing tissue damage. Although antigen specificity is an important mechanism of the adaptive immune system, antigen non-related T cells have been found in the inflamed tissues in various conditions. Bystander T cell activation refers to the activation of T cells without antigen recognition. During an immune response to a pathogen, bystander activation of self-reactive T cells via inflammatory mediators such as cytokines can trigger autoimmune diseases. Other antigen-specific T cells can also be bystander-activated to induce innate immune response resulting in autoimmune disease pathogenesis along with self-antigen-specific T cells. In this review, we summarize previous studies investigating bystander activation of various T cell types (NKT, γδ T cells, MAIT cells, conventional CD4+, and CD8+ T cells) and discuss the role of innate-like T cell response in autoimmune diseases. In addition, we also review previous findings of bystander T cell function in infection and cancer. A better understanding of bystander-activated T cells versus antigen-stimulated T cells provides a novel insight to control autoimmune disease pathogenesis.