• IMMUNE NETWORK
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• 제15권4호
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• pp.167-176
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• 2015

Macrophages are the main effector cells of innate immunity and are involved in inflammatory and anti-infective processes. They also have an essential role in maintaining tissue homeostasis, supporting tissue development, and repairing tissue damage. Until few years ago, it was believed that tissue macrophages derived from circulating blood monocytes, which terminally differentiated in the tissue and unable to proliferate. Recent evidence in the biology of tissue macrophages has uncovered a series of immune and ontogenic features that had been neglected for long, despite old observations. These include origin, heterogeneity, proliferative potential (or self-renewal), polarization, and memory. In recent years, the number of publications on tissue resident macrophages has grown rapidly, highlighting the renewed interest of the immunologists for these key players of innate immunity. This minireview aims to summarizing the new current knowledge in macrophage immunobiology, in order to offer a clear and immediate overview of the field.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 1997년도 추계학술대회 학술발표 논문집
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• pp.267-270
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• 1997

As an approach to develope a control system with robustness in changing control environment conditions, this paper will propose a robot manipulator control system using multilayer neural network and immune algorithm. The proposed immune algorithm which has the characteristics of immune system such as distributed and anomaly detection, probabilistic detection, learning and memory, consists of the innate immune algorithm and the adaptive immune algorithm. We will demonstrate the effectiveness of the proposed control system with simulations of a 2-link robot manipulator.

• IMMUNE NETWORK
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• 제4권4호
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• pp.205-215
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• 2004

In the early host defense system, effector function of natural killer (NK) cells results in natural killing against target cells such as microbe-infected, malignant, and certain allogenic cells without prior stimulation. NK cell cytotoxicity is selectively regulated by homeostatic prevalence between a repertoire of both activating and inhibitory receptors, and the discrimination of untransformed cells is achieved by recognition of major histocompatibility complex (MHC) class I alleles through inhibitory signals. Although it is well known that the bipotential T/NK progenitors are derived from the common precusor, functional mechanisms in terms of the development of NK cells remain to be further investigated. NK cells are mainly involved in innate immunity, but recent studies have been reported that they also play a critical role in adaptive immune responses through interaction with dendritic cells (DC). This interaction will provide effector functions and development of NK cells, and elucidation of its precise mechanism may lead to therapeutic strategies for effective treatment of several immune diseases.

• Food Science and Biotechnology
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• 제18권1호
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• pp.218-222
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• 2009

Ability of water extract from Prunella vulgaris Labiatae to stimulate immune system and inhibit tumor metastasis in mice was assessed. In experimental lung metastasis, prophylactic intravenous (i.v.) administration of water extract from P. vulgaris significantly inhibited lung metastasis in a dose-dependant manner. Peritoneal macrophages stimulated with P. vulgaris produced various cytokines such as tumor necrosis factor (TNF)-$\alpha$ and interlukin (IL)-12 as well as induced tumoricidal activity. In an assay for natural killer (NK) cell activity, i.v. administration of P. vulgaris significantly augmented NK cytotoxicity. The depletion of NK cells by injection of rabbit anti-asialo GM1 serum abolished the inhibitory effect of P. vulgaris on lung metastasis of colon26-M3.1 cells. These data demonstrate that P. vulgaris activate innate immune system to inhibit the growth of foreign materials including tumor cells in mice.

• Genomics & Informatics
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• 제10권3호
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• pp.153-166
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• 2012

A variety of ligands differ in their capacity to bind the receptor, elicit gene expression, and modulate physiological responses. Such receptors include Toll-like receptors (TLRs), which recognize various patterns of pathogens and lead to primary innate immune activation against invaders, and G-protein coupled receptors (GPCRs), whose interaction with their cognate ligands activates heterotrimeric G proteins and regulates specific downstream effectors, including immuno-stimulating molecules. Once TLRs are activated, they lead to the expression of hundreds of genes together and bridge the arm of innate and adaptive immune responses. We characterized the gene expression profile of Toll-like receptor 4 (TLR4) in RAW 264.7 cells when it bound with its ligand, 2-keto-3-deoxyoctonate (KDO), the active part of lipopolysaccharide. In addition, to determine the network communications among the TLR, Janus kinase (JAK)/signal transducer and activator of transcription (STAT), and GPCR, we tested RAW 264.7 cells with KDO, interferon-${\beta}$, or cAMP analog 8-Br. The ligands were also administered as a pair of double and triple combinations.

• BMB Reports
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• 제55권2호
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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.

• Fisheries and Aquatic Sciences
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• 제13권4호
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• pp.343-349
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• 2010

The effects of osmotic stress on the non-specific immune response of Nile tilapia, Oreochromis niloticus, were investigated. Osmoregulatory mechanism of tilapia has been studied, but less information is available about innate immune response of O. niloticus faced with hyperosmolality. Acute osmotic stress was elicited by transferring tilapia from freshwater (FW) to 24 psu seawater (SW). Non-specific immune parameters including lysozyme activities of plasma and head kidney (HK), alternative complement pathway (ACP) activity in plasma, phagocytic capacities of spleen and HK immune cells, and respiratory burst activity of immune cells in both HK and spleen were analyzed. Lysozyme activities were increased at 1 h and 30 h after transfer to SW, but decreased at 10 h after SW transfer. Conversely, ACP activity increased 10 h after SW transfer. Phagocytic capacity increased slightly at 1 h and 5 h after SW transfer, and respiratory burst activity showed an increase in superoxide release at 10 h after SW transfer. Taken together, these results indicate that the exposure of tilapia to hyperosmotic conditions has immunostimulatory effects on cellular and humoral immune reactions.

• 생명과학회지
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• 제29권7호
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• pp.817-823
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• 2019

노화는 광범위한 생리 변화이다. 노화가 진행됨에 따라 면역반응은 쇠퇴하고 조절장애가 나타나는데 이를 포괄적 의미로 immunosenescense라고 정의한다. 내재면역반응과 적응면역 반응 모두의 면역 성분은 노화가 진행됨에 따라 영향을 받아 감염성 질병에 대한 취약성이 증가하게 된다. 노화된 동물 모델과 인간에서 면역 세포의 수와 용해성 면역 인자의 양이 줄어 들었고, 면역체계의 기능이 감소하였고, 구조적인 변형과 퇴화가 나타났다. 또한, 세포 내 신호분자와 같은 내재적 변화도 발견되었다. 최근 노화와 관련된 연구는 급격히 증가하였고, 면역체계 영역을 포함하여 다양한 방향으로 노화현상을 분석하는 진보된 기술들이 개발되고 있다. 이 총설은 면역의 주요 구성 요소의 노화 관련 변화에 대한 광범위한 개요를 제공하고자 하였다.

• Molecules and Cells
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• 제39권9호
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• pp.680-686
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• 2016

Uncoupling proteins (UCPs) are mitochondrial inner membrane proteins that function to dissipate proton motive force and mitochondrial membrane potential. One UCP has been identified in Caenorhabditis elegans (C. elegans), namely UCP-4. In this study, we examined its expression and localization using a GFP marker in C. elegans. ucp-4 was expressed throughout the body from early embryo to aged adult and UCP-4 was localized in the mitochondria. It is known that increased mitochondrial membrane protential leads to a reactive oxygen species (ROS) increase, which is associated with age-related diseases, including neurodegenerative diseases in humans. A ucp-4 mutant showed increased mitochondrial membrane protential in association with increased neuronal defects during aging, and the neurons of ucp-4 overexpressing animals showed decreased neuronal defects during aging. These results suggest that UCP-4 may be involved in neuroprotection during aging via relieving mitochondrial membrane protential. We also investigated the relationship between UCP-4 and innate immunity because increased ROS can affect innate immunity. ucp-4 mutant displayed increased resistance to the pathogen Staphylococcus aureus compared to wild type. The enhanced immunity in the ucp-4 mutant could be related to increased mitochondrial membrane protential, presumably followed by increased ROS. In summary, UCP-4 might have an important role in neuronal aging and innate immune responses through mediating mitochondrial membrane protential.

• Molecules and Cells
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• 제25권4호
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• pp.553-558
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• 2008

Essential aspects of the innate immune response to microbial infection appear to be conserved between insects and mammals. In order to identify new Drosophila melanogaster genes involved in the immune response, we performed gene expression profiling of Drosophila SL2 cells stimulated with bacterial (LPS/PGN) or fungal (curdlan) components using a cDNA microarray that contained 5,405 Drosophila cDNAs. We found that some genes were similarly regulated by LPS/PGN and curdlan. However, a large number, belonging to the functional classes of cell organization, development, signal transduction, morphogenesis, cell cycle, and DNA replication, displayed significant differences in their transcription profiles between the two treatments, demonstrating that bacterial and fungal components induce different immune response even in an in vitro cell system.