• 제목/요약/키워드: Immune regulation

검색결과 638건 처리시간 0.032초

Regulation of Intestinal Homeostasis by Innate Immune Cells

  • Kayama, Hisako;Nishimura, Junichi;Takeda, Kiyoshi
    • IMMUNE NETWORK
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    • 제13권6호
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    • pp.227-234
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    • 2013
  • The intestinal immune system has an ability to distinguish between the microbiota and pathogenic bacteria, and then activate pro-inflammatory pathways against pathogens for host defense while remaining unresponsive to the microbiota and dietary antigens. In the intestine, abnormal activation of innate immunity causes development of several inflammatory disorders such as inflammatory bowel diseases (IBD). Thus, activity of innate immunity is finely regulated in the intestine. To date, multiple innate immune cells have been shown to maintain gut homeostasis by preventing inadequate adaptive immune responses in the murine intestine. Additionally, several innate immune subsets, which promote Th1 and Th17 responses and are implicated in the pathogenesis of IBD, have recently been identified in the human intestinal mucosa. The demonstration of both murine and human intestinal innate immune subsets contributing to regulation of adaptive immunity emphasizes the conserved innate immune functions across species and might promote development of the intestinal innate immunity-based clinical therapy.

Cellular and Molecular Links between Autoimmunity and Lipid Metabolism

  • Ryu, Heeju;Kim, Jiyeon;Kim, Daehong;Lee, Jeong-Eun;Chung, Yeonseok
    • Molecules and Cells
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    • 제42권11호
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    • pp.747-754
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    • 2019
  • The incidence of atherosclerosis is higher among patients with several autoimmune diseases such as psoriasis, rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). It is well documented that innate immune cells including macrophages and dendritic cells sense lipid species such as saturated fatty acids and oxidized low-density lipoprotein and produce pro-inflammatory cytokines and chemokines. However, whether a hyperlipidemic environment also impacts autoimmune T cell responses has been unclear. Among $CD4^+$ T cells, Th17 and follicular helper T (Tfh) cells are known to play pathogenic roles in the development of hyperlipidemia-associated autoimmune diseases. This review gives an overview of the cellular and molecular mechanisms by which dysregulated lipid metabolism impacts the pathogenesis of autoimmune diseases, with specific emphasis on Th17 and Tfh cells.

Regulation of Th2 Cell Immunity by Dendritic Cells

  • Hyeongjin Na;Minkyoung Cho;Yeonseok Chung
    • IMMUNE NETWORK
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    • 제16권1호
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    • pp.1-12
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    • 2016
  • Th2 cell immunity is required for host defense against helminths, but it is detrimental in allergic diseases in humans. Unlike Th1 cell and Th17 cell subsets, the mechanism by which dendritic cells modulate Th2 cell responses has been obscure, in part because of the inability of dendritic cells to provide IL-4, which is indispensable for Th2 cell lineage commitment. In this regard, immune cells other than dendritic cells, such as basophils and innate lymphoid cells, have been suggested as Th2 cell inducers. More recently, multiple independent researchers have shown that specialized subsets of dendritic cells mediate Th2 cell responses. This review will discuss the current understanding related to the regulation of Th2 cell responses by dendritic cells and other immune cells.

Post-transcriptional Regulation of NK Cell Activation

  • Kim, Tae-Don;Park, Ju-Yeong;Choi, In-Pyo
    • IMMUNE NETWORK
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    • 제9권4호
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    • pp.115-121
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    • 2009
  • Natural killer (NK) cells play key roles in innate and adaptive immune defenses. NK cell responses are mediated by two major mechanisms: the direct cytolysis of target cells, and immune regulation by production of various cytokines. Many previous reports show that the complex NK cell activation process requires de novo gene expression regulated at both transcriptional and post-transcriptional levels. Specialized un-translated regions (UTR) of mRNAs are the main mechanisms of post-transcriptional regulation. Analysis of posttranscriptional regulation is needed to clearly understand NK cell biology and, furthermore, harness the power of NK cells for therapeutic aims. This review summarizes the current understanding of mRNA metabolism during NK cell activation, focusing primarily on post-transcriptional regulation.

Regulation of the Immune System by NF-κB and IκB

  • Liou, Hsiou-Chi
    • BMB Reports
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    • 제35권6호
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    • pp.537-546
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    • 2002
  • NF-${\kappa}B$/Rel transcription factor family participates in diverse biological processes including embryo development, hematopoiesis, immune regulation, as well as neuronal functions. In this review, the NF-${\kappa}B$/Rel signal transduction pathways and their important roles in the regulation of immune system will be discussed. NF-${\kappa}B$/Rel members execute distinct functions in multiple immune cell types via the regulation of target genes essential for cell proliferation, survival, effector functions, cell trafficking and communication, as well as the formation of lymphoid architecture. Consequently, proper activation of NF-${\kappa}B$/Rel during immune responses to allergens, auto-antigens, allo-antigens, and pathogenic infection is crucial for the integrity of host innate and adaptive immunity.

Regulation of Innate Immune Response to Fungal Infection in Caenorhabditis elegans by SHN-1/SHANK

  • Sun, Lingmei;Li, Huirong;Zhao, Li;Liao, Kai
    • Journal of Microbiology and Biotechnology
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    • 제30권11호
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    • pp.1626-1639
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    • 2020
  • In Caenorhabditis elegans, SHN-1 is the homologue of SHANK, a scaffolding protein. In this study, we determined the molecular basis for SHN-1/SHANK in the regulation of innate immune response to fungal infection. Mutation of shn-1 increased the susceptibility to Candida albicans infection and suppressed the innate immune response. After C. albicans infection for 6, 12, or 24 h, both transcriptional expression of shn-1 and SHN-1::GFP expression were increased, implying that the activated SHN-1 may mediate a protection mechanism for C. elegans against the adverse effects from fungal infection. SHN-1 acted in both the neurons and the intestine to regulate the innate immune response to fungal infection. In the neurons, GLR-1, an AMPA ionotropic glutamate receptor, was identified as the downstream target in the regulation of innate immune response to fungal infection. GLR-1 further positively affected the function of SER-7-mediated serotonin signaling and antagonized the function of DAT-1-mediated dopamine signaling in the regulation of innate immune response to fungal infection. Our study suggests the novel function of SHN-1/SHANK in the regulation of innate immune response to fungal infection. Moreover, our results also denote the crucial role of neurotransmitter signals in mediating the function of SHN-1/SHANK in regulating innate immune response to fungal infection.

Innate Type-2 Cytokines: From Immune Regulation to Therapeutic Targets

  • Hye Young Kim;Dongjin Jeong;Ji Hyung Kim;Doo Hyun Chung
    • IMMUNE NETWORK
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    • 제24권1호
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    • pp.6.1-6.17
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    • 2024
  • The intricate role of innate type-2 cytokines in immune responses is increasingly acknowledged for its dual nature, encompassing both protective and pathogenic dimensions. Ranging from defense against parasitic infections to contributing to inflammatory diseases like asthma, fibrosis, and obesity, these cytokines intricately engage with various innate immune cells. This review meticulously explores the cellular origins of innate type-2 cytokines and their intricate interactions, shedding light on factors that amplify the innate type-2 response, including TSLP, IL-25, and IL-33. Recent advancements in therapeutic strategies, specifically the utilization of biologics targeting pivotal cytokines (IL-4, IL-5, and IL-13), are discussed, offering insights into both challenges and opportunities. Acknowledging the pivotal role of innate type-2 cytokines in orchestrating immune responses positions them as promising therapeutic targets. The evolving landscape of research and development in this field not only propels immunological knowledge forward but also holds the promise of more effective treatments in the future.

Expression and regulation of avian beta-defensin 8 protein in immune tissues and cell lines of chickens

  • Rengaraj, Deivendran;Truong, Anh Duc;Lillehoj, Hyun S.;Han, Jae Yong;Hong, Yeong Ho
    • Asian-Australasian Journal of Animal Sciences
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    • 제31권9호
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    • pp.1516-1524
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    • 2018
  • Objective: Defensins are a large family of antimicrobial peptides and components of the innate immune system that invoke an immediate immune response against harmful pathogens. Defensins are classified into alpha-, beta-, and theta-defensins. Avian species only possess beta-defensins (AvBDs), and approximately 14 AvBDs (AvBD1-AvBD14) have been identified in chickens to date. Although substantial information is available on the conservation and phylogenetics, limited information is available on the expression and regulation of AvBD8 in chicken immune tissues and cells. Methods: We examined AvBD8 protein expression in immune tissues of White Leghorn chickens (WL) by immunohistochemistry and quantitative reverse transcription-polymerase chain reaction (RT-qPCR). In addition, we examined AvBD8 expression in chicken T-, B-, macrophage-, and fibroblast-cell lines and its regulation in these cells after lipopolysaccharide (LPS) treatment by immunocytochemistry and RT-qPCR. Results: Our results showed that chicken AvBD8 protein was strongly expressed in the WL intestine and in macrophages. AvBD8 gene expression was highly upregulated in macrophages treated with different LPS concentrations compared with that in T- and B-cell lines in a time-independent manner. Moreover, chicken AvBD8 strongly interacted with other AvBDs and with other antimicrobial peptides as determined by bioinformatics. Conclusion: Our study provides the expression and regulation of chicken AvBD8 protein in immune tissues and cells, which play crucial role in the innate immunity.

Positive and negative regulation of the Drosophila immune response

  • Aggarwal, Kamna;Silverman, Neal
    • BMB Reports
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    • 제41권4호
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    • pp.267-277
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    • 2008
  • Insects mount a robust innate immune response against a wide array of microbial pathogens. The hallmark of the Drosophila humoral immune response is the rapid production of anti-microbial peptides in the fat body and their release into the circulation. Two recognition and signaling cascades regulate expression of these antimicrobial peptide genes. The Toll pathway is activated by fungal and many Gram-positive bacterial infections, whereas the immune deficiency (IMD) pathway responds to Gram-negative bacteria. Recent work has shown that the intensity and duration of the Drosophila immune response is tightly regulated. As in mammals, hyperactivated immune responses are detrimental, and the proper down-modulation of immunity is critical for protective immunity and health. In order to keep the immune response properly modulated, the Toll and IMD pathways are controlled at multiple levels by a series of negative regulators. In this review, we focus on recent advances identifying and characterizing the negative regulators of these pathways.

LPS로 급성 염증을 유발한 동물에 대한 용담초 추출물의 면역조절 효과 (Immune regulation effects of Gentianae Radix extract in LPS-induced acute inflammatory mice)

  • 이효정;승윤철;이명선
    • 대한본초학회지
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    • 제33권2호
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    • pp.79-84
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    • 2018
  • Objective : The immune enhance is the main focus of current society that to increase resistance to invasion by pathogenic species of bacteria in body, stimulate the immune system and possibly protect against cancer or inflammatory disease. The present study aimed to evaluate the effect of Gentianae Radix extract on immune regulation in a LPS-induced mice model of acute inflammation. Methods : Gentianae Radix extract was administered orally at doses of 200 mg/kg/day or 400 mg/kg/day for 2 weeks before a intraperitoneally injection of LPS (1 mg/kg of 0.9% saline). After LPS-intraperitoneal injection 3 hours, blood was collected by cardiac puncture under ether anaesthesia from all animals, for the immune regulate efficacy verification based on blood or serum biomarkers (i.e., immune cells, cytokine, $PGE_2$, ROS, and $LTB_4$) analysis. Results : Compared to the control mice, the Gentianae Radix extract treatments significantly increased the count of immune cells (i.e., wite blood cell, neutrophils, and monocyte), and significantly reduced the lymphocyte. In addition, the Gentianae Radix extract treatments significantly decreased the pro-inflammatory cytokine (i.e., $IL-1{\beta}$, IL-6, and $TNF-{\alpha}$), and significantly increased IL-10 of anti-inflammatory cytokine. Furthermore, the Gentianae Radix extracts treatments significantly increased the levels of $PGE_2$ and significantly decreased the levels of ROS, and $LTB_4$. Conclusions : The results indicate that Gentianae Radix extract alleviated acute inflammatory reaction though regulation of immune meditor. Thus, Gentianae Radix extract may raw material of development a health food and medicine option for the immune enhance.