自然殺虫細胞の信号伝達経路は,自然殺虫細胞の信号伝達経路である
Eric Vivier1, Jacques A Nunès, Frédéric Vély
1Centre d'Immunologie de Marseille-Luminy, INSERM-CNRS-Univ. Méditerranée, Campus de Luminy, Case 906, 13288 Marseille cedex 09, France. vivier@ciml.univ-mrs.fr
Science (New York, N.Y.)
|November 30, 2004
まとめ
自然キラー (NK) 細胞は,活性化受容体と抑制受容体を用いて,ストレスを受けた細胞に対する免疫反応をバランスとします. これらの信号伝達経路を理解することは,NK細胞の機能を操作する鍵です.
科学分野:
- 免疫学 免疫学とは
- 細胞生物学 細胞生物学
- 分子シグナリング
背景:
- 自然キラー (NK) 細胞は,重要な先天性免疫リンパ球である.
- 感染症や腫瘍の変容に抵抗します.
- NK細胞の活性化は,活性化信号と抑制信号のバランスに依存しています.
研究 の 目的:
- NK細胞の活性化を制御するシグナル伝達経路の解明.
- 様々なNK細胞受容体からの信号の統合を理解する.
- NK細胞エフェクター機能を操作するための洞察を提供するため.
主な方法:
- NK細胞の細胞表面受容体の活性化および抑制の分析.
- タンパク質チロシンキナーゼ (PTK) とフォスファタゼ (PTP) を含む下流信号伝達経路の調査.
- DAP10のようなアダプターやITAMやITIMのようなモチーフの検討.
主要な成果:
- NK細胞の活性化には,ITAMに依存する経路と独立した経路の両方が含まれます.
- NKG2Dのような受容体は,DAP10のようなアダプターと結合する.
- ITIMを持つ阻害性受容体は,PTP経由で活性化を阻害する.
結論:
- PTKとPTPの活性のバランスは,NK細胞のエフェクタ機能に極めて重要です.
- 信号統合を理解することは,NK細胞の反応を制御するために不可欠です.
- この知識は,NK細胞媒介免疫の操作に役立ちます.
関連する概念動画
01:21Cell-surface Signaling
Hormones—or any molecule that binds to a receptor, known as a ligand—that are lipid-insoluble (water-soluble) are not able to diffuse across the cell membrane. In order to be able to affect a cell without entering it, these hormones bind to receptors on the cell membrane. When a first messenger, a hormone, binds to a receptor, a signal cascade is set off, causing second messengers, proteins inside the cell, to become activated, resulting in downstream effects.
01:30Overview of Cell Death
Cell death is an essential process where the body gets rid of old or damaged cells. Cell proliferation and death need to be balanced, as an imbalance between the two may lead to cancer or autoimmune diseases.
Cell death was observed in the early 19th century, but there was no experimental evidence to prove it. In 1842, Carl Vogt first discovered cell death in a metamorphic toad; however, it was not termed ‘cell death.’ Scientists discovered different cell death pathways only in the 20th century...
Cell death was observed in the early 19th century, but there was no experimental evidence to prove it. In 1842, Carl Vogt first discovered cell death in a metamorphic toad; however, it was not termed ‘cell death.’ Scientists discovered different cell death pathways only in the 20th century...
01:17The Extrinsic Apoptotic Pathway
The extrinsic apoptotic pathway is initiated when extracellular death-inducing signals, such as specific cytokines, activate the death receptors expressed on the cell surface. The immune cells involved in this pathway are natural killer cells (NK cells) and cytotoxic T-lymphocytes. NK cells are critical in innate immune response, while cytotoxic T-lymphocytes are associated with adaptive immune response. These cells recognize specific receptors expressed on the altered cells and activate...
01:17Phagocytosis of Apoptotic Cells
Cells undergoing apoptosis form apoptotic bodies that must be removed immediately to prevent inflammation, autoimmune diseases, and necrosis. Phagocytosis is carried out by professional phagocytes such as macrophages or immature dendritic cells. Non-professional phagocytes such as epithelial cells and fibroblasts also take part in this process; however, they are not as effective as professional phagocytes.
Normal cells contain receptors that prevent them from being recognized by phagocytes.
Normal cells contain receptors that prevent them from being recognized by phagocytes.
01:28Cells of the Innate Immune Response
The innate immune response is an immediate and non-specific response against pathogens, acting swiftly to prevent the spread of infections. The primary cells involved in this response are phagocytes and natural killer (NK) cells.
Phagocytes
Phagocytes police the peripheral tissues by removing cellular debris and responding to the invasion of foreign substances or pathogens. Many phagocytes attack and remove microorganisms even before lymphocytes detect them. The human body has two general...
Phagocytes
Phagocytes police the peripheral tissues by removing cellular debris and responding to the invasion of foreign substances or pathogens. Many phagocytes attack and remove microorganisms even before lymphocytes detect them. The human body has two general...
01:25Immune Surveillance by NK Cells and Phagocytes
Immune surveillance is an integral part of the innate immune system, involving the continuous monitoring of peripheral tissues to detect and respond to pathogens, infected cells, or cancerous cells. This surveillance is conducted primarily by natural killer (NK) cells and phagocytes, which employ distinct but complementary mechanisms to identify and eliminate threats.
Natural Killer Cells: The Fast Responders
NK cells are large granular lymphocytes found in the blood and lymphatic system. These...
Natural Killer Cells: The Fast Responders
NK cells are large granular lymphocytes found in the blood and lymphatic system. These...