Related Experiment Video
Updated: Oct 19, 2025
07:44
Studying the Effects of Tumor-Secreted Paracrine Ligands on Macrophage Activation using Co-Culture with Permeable Membrane Supports
Published on: November 28, 2019
7.7K
Amateur antigen-presenting cells in the tumor microenvironment
Laurel B Darragh1, Sana D Karam2
1Department of Immunology, University of Colorado Denver-Anschutz Medical Campus, Aurora, CO, USA.
Molecular Carcinogenesis
|September 27, 2021
Summary
Tumor antigen presentation is crucial for antitumor immunity. Recent evidence shows "amateur" antigen-presenting cells (aAPCs) in the tumor microenvironment (TME) also present antigens, potentially enhancing immunotherapies.
Area of Science:
- Immunology
- Oncology
- Cell Biology
Background:
- Antitumor immune responses rely on tumor antigen presentation.
- Professional antigen-presenting cells (pAPCs) classically present antigens via MHC I and II.
- The tumor microenvironment (TME) contains diverse cell types beyond pAPCs.
Purpose of the Study:
- To review evidence of non-professional antigen presentation in the TME.
- To highlight the role of "amateur" antigen-presenting cells (aAPCs) in tumor immunity.
- To explore new immunotherapy strategies based on aAPC function.
Main Methods:
- Literature review of studies on antigen presentation by non-pAPCs.
- Analysis of evidence for MHC I and II presentation by various cell types.
- Synthesis of findings regarding the role of aAPCs in the TME.
Main Results:
- Epithelial cells, vascular endothelial cells (VECs), fibroblasts, and cancer cells can present tumor antigens.
- These non-pAPCs, termed aAPCs, are abundant in the TME.
- aAPCs are capable of presenting antigens on both MHC I and II.
Conclusions:
- aAPCs significantly contribute to antigen presentation within the TME.
- The abundance and function of aAPCs offer novel targets for cancer immunotherapy.
- Rethinking antigen presentation pathways can lead to improved T cell priming strategies.
Related Concept Videos
02:17The Tumor Microenvironment
7.0K
Every normal cell or tissue is embedded in a complex local environment called stroma, consisting of different cell types, a basal membrane, and blood vessels. As normal cells mutate and develop into cancer cells, their local environment also changes to allow cancer progression. The tumor microenvironment (TME) consists of a complex cellular matrix of stromal cells and the developing tumor. The cross-talk between cancer cells and surrounding stromal cells is critical to disrupt normal tissue...
7.0K
01:22Antigen Presenting Cells
2.3K
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...
2.3K
01:27Tumor Immunotherapy
741
Immunotherapy is a treatment that boosts or manipulates the immune system to fight diseases, including cancer. For instance, by stimulating an immune response through vaccinations against viruses that cause cancers, like hepatitis B virus and human papillomavirus, these diseases can be prevented. Nonetheless, some cancer cells can avoid the immune system due to their rapid mutation and division. The immune response to many cancers involves three phases: elimination, equilibrium, and escape.
741
01:26Antigens Involved in Adaptive Immunity
791
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...
Complete Antigens
Complete antigens possess both immunogenicity and...
791
01:31Antigen Processing Pathways
1.5K
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...
1.5K