関連する実験動画
Updated: Dec 7, 2025

10:23
Evaluation of Caspase Activation to Assess Innate Immune Cell Death
Published on: January 20, 2023
3.6K
N4BP1のカスパース-8分裂による先天性免疫信号の統合
Alexander D Gitlin1,2, Klaus Heger3, Alexander F Schubert4
1Department of Pathology, Stanford University School of Medicine, Stanford, CA, USA. adgitlin@stanford.edu.
Nature
|September 24, 2020
まとめ
NEDD4結合タンパク質1 (N4BP1) は,サイトカインの産生を抑制し,カスパース8によって不活性化されます. カスパース-8による分裂は炎症信号を統合し,カスパース-8変異に関連した免疫不全を説明します.
科学分野:
- 免疫学
- 分子生物学
- 細胞シグナリング
背景:
- FAS,FASL,caspase-8またはFADDの変異は,自己免疫リンパ増殖症候群と重度の免疫不全に関連しています.
- FADD-caspase-8経路の欠陥に関連した免疫不全の正確なメカニズムは不明である.
- カスパース8は免疫反応と細胞死経路において重要な役割を果たします.
研究 の 目的:
- 免疫反応に関与するサイトカイン産生の新しい調節体を特定する.
- 炎症シグナル伝達におけるNEDD4結合タンパク質1 (N4BP1) の役割を解明する.
- カスパース-8の活性がN4BP1の機能とサイトカインの産生にどのように影響するかを理解する.
主な方法:
- 標的型遺伝子消去 (N4BP1,カスパース-8) のマウスモデルを使用した.
- マクロファージのトール型受容体 (TLR) 1/ 2, 3, 4, 7, 9を刺激する.
- 様々な刺激や遺伝子改変に対する反応として,サイトカインの産生とN4BP1の分裂を評価した.
主要な成果:
- カスパース8分裂によって不活性化されるサイトカイン生成抑制剤としてN4BP1を特定した.
- N4BP1の消去はTLR1/2,TLR7およびTLR9経由でのサイトカイン生成を増加させたが,TLR3またはTLR4経由での生産は増加しなかった.
- TLR3およびTLR4刺激に対する強固なサイトカイン応答とTNFシグナル伝達には,カスパース8依存のN4BP1分裂が必要であった.
結論:
- N4BP1は,サイトカイン反応の強力な抑制剤として作用する.
- カスパース8によるN4BP1の分裂は,炎症信号の重要な統合点として機能する.
- このメカニズムは,FADDとカスパース-8変異を有する個体で観察された免疫不全を説明します.
関連する概念動画
Caspases
13.3K
Caspase, a family of cysteine proteases, serve as effectors in apoptosis. The ced3 gene in C.elegans was first identified to be involved in apoptosis. This gene encodes the ced-3 caspase that is similar to the interleukin-1-beta converting enzyme or ICE in mammals. In addition to apoptosis, caspases also function in the inflammatory response. Inflammatory caspases are essential in activating pro-inflammatory cytokines that recruit immune cells and block the replication of pathogens inside...
13.3K
The Extrinsic Apoptotic Pathway
7.6K
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...
7.6K
The Intrinsic Apoptotic Pathway
7.8K
Internal cellular stress, such as cellular injury or hypoxia, triggers intrinsic apoptosis. The B-cell lymphoma 2 (Bcl-2) family of proteins are the primary regulators of the intrinsic apoptotic pathway. For example, during DNA damage, checkpoint proteins, such as Ataxia Telangiectasia Mutated (ATM protein) and Checkpoints Factor-2 (Chk2) proteins, are activated. These proteins phosphorylate p53 which further activates pro-apoptotic proteins, such as Bax, Bak, PUMA, and Noxa, and inhibits...
7.8K
NF-κB-dependent Signaling Pathway
9.5K
The transcription factor NF-κB was discovered in 1986 in the lab of Nobel laureate Professor David Baltimore, for its interaction with the immunoglobulin light chain enhancer in B-cells. After more than three decades of study, it is now evident that NF-κB regulates the expression of over 100 genes. Most of these genes play an essential role in the innate and adaptive immune responses as well as the inflammatory responses of animals.
NF-κB-dependent Signaling Mechanism
The...
NF-κB-dependent Signaling Mechanism
The...
9.5K
Apoptosis
13.3K
Apoptosis is a combination of two Greek words, 'apo' and 'ptosis,' meaning separation and falling off, respectively. Hippocrates used this word to describe gangrene, which was caused due to bandaging of fractured bones. Apoptosis was distinguished from necrosis in 1970 when John Kerr reported observations of morphological changes occurring during apoptosis. During one experiment, he observed that the disruption of blood supply to the liver tissue resulted in a size...
13.3K
Phagocytosis of Apoptotic Cells
4.5K
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...
Normal cells contain receptors that prevent them from being recognized...
4.5K

