Molecular Classification
Cellular Process, Immune Function
Other Names
Antigen Presentation, APC Activity, MHC Presentation
Disease Roles
ImmunodeficiencyAutoimmunityChronic infection susceptibility

Antigen-Presenting Cell Function Overview

Antigen-presenting cell (APC) function refers to the process by which certain immune cells detect, process, and display antigens on their surface in a form recognizable to T cells. This is a critical step in initiating and regulating adaptive immune responses. The main professional APCs are dendritic cells, macrophages, and B lymphocytes. APCs capture pathogens or foreign molecules, degrade them into peptide fragments, load them onto MHC molecules, and display the antigen-MHC complexes on the cell surface for recognition by T cell receptors. APCs also provide co-stimulatory signals and secrete cytokines to fully activate T cells. Defects in antigen presentation can result in immunodeficiency, autoimmunity, chronic infection susceptibility, or failure of tumor surveillance. Manipulation of this function is central in vaccine development and immunotherapy strategies.

Mechanism of Action

N/A

Biological Functions

Antigen uptake
Antigen processing
MHC loading
T cell activation
Co-stimulation

Disease Associations

Immunodeficiency
Autoimmunity
Chronic infection susceptibility
Cancer
Inflammation

Safety Considerations

  • Off-target immune activation
  • Cytokine release syndrome
  • Autoimmunity

Interacting Drugs

Immunosuppressants
Immunomodulators
Vaccines
Checkpoint inhibitors

Associated Biomarkers

Biomarker
MHC expression levels
Costimulatory molecule expression
Cytokine production
T cell activation markers