Related Experiment Video
Updated: Aug 8, 2026
12:48
Purification of the Membrane Compartment for Endoplasmic Reticulum-associated Degradation of Exogenous Antigens in Cross-presentation
Published on: August 21, 2017
Autophagy and antigen presentation
1Laboratory of Viral Immunobiology and Christopher H. Browne Center for Immunology and Immune Diseases, The Rockefeller University, New York, NY 10021, USA. munzc@rockefeller.edu
Cellular Microbiology
|May 10, 2006
Summary
This review explores how autophagy delivers endogenous antigens for MHC class II presentation, crucial for CD4(+) T cell responses and immune memory. Understanding these pathways enhances insights into immune surveillance of infections and tumors.
Area of Science:
- Immunology
- Cell Biology
Background:
- CD4(+) T cells coordinate adaptive immunity and immunological memory.
- They typically recognize extracellular antigens presented on MHC class II molecules.
- Endogenous antigens can access this pathway via autophagy.
Purpose of the Study:
- To discuss autophagic pathways for endogenous MHC class II antigen processing.
- To consider characteristics of autophagy substrates and regulation.
- To suggest how autophagy-mediated antigen presentation aids immune surveillance.
Main Methods:
- Literature review of studies on autophagy and MHC class II antigen presentation.
- Analysis of mechanisms by which endogenous antigens access antigen processing pathways.
- Discussion of regulatory aspects of autophagy relevant to antigen presentation.
Main Results:
- Autophagy provides a route for endogenous antigens (viral, tumor, autoantigens) to reach MHC class II presentation pathways.
- Specific characteristics of autophagy substrates facilitate their entry into these pathways.
- Autophagy regulation plays a key role in this process.
Conclusions:
- Autophagy is a significant mechanism for endogenous antigen processing and presentation on MHC class II.
- This pathway is critical for CD4(+) T cell activation against intracellular threats.
- Autophagy-mediated antigen presentation contributes to immune surveillance of infected and transformed cells.
Related Concept Videos
01:31Antigen Processing Pathways
MHC molecules are key players in the immune response, enabling T cells to recognize and respond to specific antigens. They are present on the surface of all nucleated cells in the body and are instrumental in presenting antigens to T cells and activating them. T cells recognize the MHC-antigen complex and initiate an immune response. MHC class I and MHC class II are two main types of MHC molecules, each associated with a distinct antigen processing pathway.
MHC Class I: Presenting Endogenous...
MHC Class I: Presenting Endogenous...
01:22Antigen Presenting Cells
The immune system is a complex network of cells and molecules that protects the body from foreign invaders. T cells, a type of white blood cell, play a crucial role in this process. They recognize and attack foreign substances, such as pathogens, that enter the body.
T cells require the help of antigen-presenting cells (APCs), which process foreign antigens into smaller fragments that can be recognized by T cells. These APCs are highly specialized cells that efficiently internalize antigens...
T cells require the help of antigen-presenting cells (APCs), which process foreign antigens into smaller fragments that can be recognized by T cells. These APCs are highly specialized cells that efficiently internalize antigens...
01:36Delivery Pathways to the Lysosome
Eukaryotic cells use different mechanisms to eliminate toxic waste obsolete and worn-out substances. Lysosomes play a pivotal role in this, and hence, these substances are carried to the lysosome from other parts of the cell and extracellular space through different pathways. The most elaborately studied pathways to the lysosome are the endocytic pathways.
Endocytosis
In endocytosis, the cell membrane takes up macromolecules and particles from the surrounding medium. Clathrin-mediated...
Endocytosis
In endocytosis, the cell membrane takes up macromolecules and particles from the surrounding medium. Clathrin-mediated...
01:26Antigens Involved in Adaptive Immunity
An antigen is any substance the immune system identifies as foreign and potentially harmful to the body, prompting an immune response. Antigens have two functional properties: immunogenicity and reactivity. Immunogenicity is the ability of an antigen to stimulate a specific immune response. At the same time, reactivity describes the antigen's ability to react with the cells and antibodies produced in response to it.
Complete Antigens
Complete antigens possess both immunogenicity and reactivity.
Complete Antigens
Complete antigens possess both immunogenicity and reactivity.
01:27Autophagy
Autophagy is a self-digesting process by which a cell protects itself from threats both within and outside the cell, ranging from abnormal proteins to invading bacteria. In this process, obsolete components of the cell and invading microbes are degraded by hydrolytic enzymes active in an acidic environment of the lysosomal lumen.
An autophagic pathway consists of a series of signaling events activated in response to diverse stress and physiological conditions such as food deprivation,...
An autophagic pathway consists of a series of signaling events activated in response to diverse stress and physiological conditions such as food deprivation,...
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.