Related Experiment Video
Updated: Jun 18, 2026
14:29
Examination of Thymic Positive and Negative Selection by Flow Cytometry
Published on: October 8, 2012
Antigen presentation in the thymus for positive selection and central tolerance induction
Ludger Klein1, Maria Hinterberger, Gerald Wirnsberger
1Institute for Immunology, Ludwig-Maximilians University, Goethestrasse 31, 80336 Munich, Germany. ludger.klein@med.lmu.de
Nature Reviews. Immunology
|November 26, 2009
Summary
Thymic selection establishes T cell tolerance by shaping the self-peptide-MHC ligand repertoire. Recent discoveries reveal unique antigen presentation in the thymus, highlighting cooperative roles of stromal cells in T cell selection.
Area of Science:
- Immunology
- Cell Biology
Background:
- Thymic selection is crucial for T cell repertoire development, ensuring self-tolerance.
- Understanding self-peptide-MHC complex restriction requires knowledge of thymic antigen-presenting cells (APCs) and their interactions with T cells.
Purpose of the Study:
- To discuss recent findings on antigen presentation within the thymic microenvironment.
- To explore how distinct thymic stromal cell types cooperate in T cell selection.
Main Methods:
- Review of recent discoveries in antigen processing, APC heterogeneity, and intercellular antigen transfer.
- Analysis of thymic stromal cell interactions in T cell selection.
Main Results:
- Unique aspects of antigen presentation have been uncovered, including cortex-specific antigen processing pathways.
- Heterogeneity among thymic dendritic cells influences antigen presentation.
- Intercellular transfer of self-antigens plays a role in the thymic microenvironment.
Conclusions:
- Thymic stromal cells support T cell selection in a cooperative, non-redundant manner.
- New insights into thymic APCs and antigen presentation refine our understanding of T cell tolerance induction.
Related Concept Videos
01:22T Cell Activation and Clonal Selection
T cells are integral to our adaptive immune system, recognizing and effectively responding to foreign antigens. T cell activation and clonal selection are pivotal in orchestrating this immune response. This article elucidates these mechanisms, detailing the roles of cluster of differentiation (CD) markers, major histocompatibility complex (MHC) molecules, costimulatory signals, and the process of clonal selection.
Naive T cells that have not yet encountered an antigen express two primary CD...
Naive T cells that have not yet encountered an antigen express two primary CD...
01:20Special Features of Adaptive Immunity
The adaptive immune system, a crucial component of the overall immune response, offers a highly specialized defense against pathogens. It involves specific cell types and features, enabling it to combat infections effectively and efficiently.
The primary cell types involved in adaptive immunity are T cells and B cells. Each type has a unique role in defending the body against pathogens. T cells are responsible for cell-mediated immunity. They identify and eliminate infected cells directly,...
The primary cell types involved in adaptive immunity are T cells and B cells. Each type has a unique role in defending the body against pathogens. T cells are responsible for cell-mediated immunity. They identify and eliminate infected cells directly,...
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.
01:22Antigen 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...
01:24B Cell Activation and Differentiation
The adaptive immune response, a sophisticated defense mechanism, relies on the activation and differentiation of B lymphocytes, or B cells. These processes enable our bodies to mount a tailored response against specific pathogens such as bacteria, free virus particles, toxins, and parasites.
When naive B cells encounter a specific antigen that can bind to the B cell receptor (BCR) on their surface, they undergo sensitization to respond to the antigen's presence. Sensitization begins with...
When naive B cells encounter a specific antigen that can bind to the B cell receptor (BCR) on their surface, they undergo sensitization to respond to the antigen's presence. Sensitization begins with...
01:23Cells of the Adaptive Immune Response
The T and B lymphocytes of the adaptive immune system develop from common lymphoid progenitor cells in the bone marrow. These progenitors give rise to precursors that eventually develop into both T and B lymphocytes. As these precursors mature, they gain the ability to detect and respond to foreign antigens in the body, a process known as immunocompetence. Additionally, these precursors acquire self-tolerance, a process that ensures they do not react to self-antigens. This intricate system...