Related Experiment Video
Updated: Aug 14, 2026
06:22
Multicolor Flow Cytometry-based Quantification of Mitochondria and Lysosomes in T Cells
Published on: January 9, 2019
Mitochondria-dependent apoptosis in T-cell homeostasis
Marina Grimaldi1, Mélanie Denizot, Lucile Espert
1Laboratoire 'Infections Rétrovirales et Signalisation Cellulaire, CNRS UMR 5121, Institut de Biologie, 4 Bd Henri IV, CS 89508, 34960 Montpellier 2, France.
Current Opinion in Investigational Drugs (London, England : 2000)
|November 30, 2005
Summary
Regulated cell death, known as apoptosis, is crucial for maintaining a stable immune system by balancing lymphocyte proliferation and destruction. This process is vital for T-cell development and immune response control, with therapeutic potential.
Area of Science:
- Immunology
- Cell Biology
- Molecular Biology
Background:
- T-cell homeostasis relies on a balance between lymphocyte proliferation and cell death.
- Mitochondria-dependent apoptosis plays a critical role in immune system development and maintenance.
- Apoptosis ensures a constant lymphocyte count throughout an individual's life.
Purpose of the Study:
- To highlight the essential role of apoptosis in T-cell development and immune system regulation.
- To underscore the importance of controlled T-cell selection during thymic maturation.
- To emphasize apoptosis's function in managing T-cell expansion post-activation.
Main Methods:
- Review of existing literature on T-cell development and apoptosis.
- Analysis of the molecular mechanisms of mitochondria-dependent apoptosis.
- Examination of the consequences of dysregulated apoptosis in T-cell populations.
Main Results:
- Apoptosis is indispensable for sequential T-cell maturation stages in the thymus.
- Controlled apoptosis is essential for regulating the expansion of antigen-specific T-cells.
- Failures in apoptotic regulation can result in various immune pathologies.
Conclusions:
- Mitochondria-dependent apoptosis is a key regulator of T-cell homeostasis.
- Targeting apoptosis pathways offers potential therapeutic strategies for immune disorders.
- Maintaining proper T-cell apoptosis is critical for immune system integrity.
Related Concept Videos
01:30Apoptosis
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 reduction of the tissue.
01:31The Intrinsic Apoptotic Pathway
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...
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...
01:22Cellular Injury V: Apoptosis and Autophagy
Cells respond to damage and stress through highly coordinated processes that decide whether they survive or undergo controlled self-destruction. Two major pathways involved in this regulation are apoptosis, a type of programmed cell death, and autophagy, a survival mechanism that helps cells adapt to adverse conditions.ApoptosisApoptosis removes aged or injured cells to maintain tissue balance. During this process, the cell shrinks, chromatin condenses and fragments, and membrane-bound...
01:27Cytotoxic T Cells-mediated Immune Response
Cytotoxic T cells are a vital component of the immune system. They have the remarkable ability to identify and target antigens on infected or abnormal cells. These antigens often originate from intracellular pathogens such as viruses or abnormal proteins cancer cells produce.
Immunological surveillance is the ability of immune cells to monitor and eliminate infected cells with intracellular pathogens, neoplastically transformed cells, and cells with non-self antigens. Cytotoxic T cells and NK...
Immunological surveillance is the ability of immune cells to monitor and eliminate infected cells with intracellular pathogens, neoplastically transformed cells, and cells with non-self antigens. Cytotoxic T cells and NK...
01:18Autophagic Cell Death
Christian de Duve discovered “autophagy,” a process in which cellular components are engulfed by membrane-bound organelles called autophagosomes. The autophagosomes then fuse with lysosomes to digest the enclosed contents. Autophagy is generally activated in cells to prevent cell death. However, cell death is triggered when the damage is beyond repair.
Autophagy and Apoptosis
Autophagy can activate apoptosis. In normal conditions, the autophagy activating protein Beclin-1 and pro-apoptotic...
Autophagy and Apoptosis
Autophagy can activate apoptosis. In normal conditions, the autophagy activating protein Beclin-1 and pro-apoptotic...