Apoptosis in the regulation of immune responses

Michael J Pinkoski1, Douglas R Green

  • 1Division of Cellular Immunology, La Jolla Institute for Allergy and Immunology, San Diego, California, USA.

Insights

Programmed cell death, or apoptosis, regulates immune responses. T cell apoptosis protects against immune-mediated damage, with research clarifying caspase activation and death pathways.

Area of Science:

  • Immunology
  • Cell Biology

Background:

  • Apoptosis, or programmed cell death, is crucial for regulating immune responses.
  • T cell apoptosis serves as a protective mechanism against potential damage during immune responses.

Purpose of the Study:

  • To review the biological processes underlying the morphological aspects of apoptosis.
  • To elucidate the mechanisms of caspase activation, death pathways, and receptor-ligand interactions in T cell apoptosis.

Main Methods:

  • Literature review of current research on apoptosis.
  • Analysis of molecular mechanisms including caspase activation and death receptor signaling.

Main Results:

  • Apoptosis is an active, regulated process essential for immune homeostasis.
  • T cell apoptosis plays a key role in preventing autoimmune or inflammatory damage.
  • Understanding of death pathways and ligand-receptor crosstalk is advancing.

Conclusions:

  • Programmed cell death is integral to immune system regulation.
  • T cell apoptosis is a vital protective mechanism.
  • Further research is defining the molecular intricacies of apoptotic pathways.

Related Concept Videos

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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.
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The Extrinsic Apoptotic Pathway

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Cellular Injury V: Apoptosis and Autophagy

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Phagocytosis of Apoptotic Cells

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The 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...