antigen-presenting cell

noun

an·​ti·​gen-pre·​sent·​ing cell ˈan-ti-jən-pri-ˈzen-tiŋ- 

-ˌjen-

plural antigen-presenting cells

: any of various cells (such as a dendritic cell, macrophage, or B cell) that take up and process an antigen into a peptide fragment which when displayed at the cell surface in combination with a molecule of the major histocompatibility complex is recognized by and serves to activate cells of the immune system (such as helper T cells or cytotoxic T cells)

His images showed interactions between immune cells called antigen-presenting cells (APCs) that specialize in breaking up proteins belonging to an invader, such as a virus, and displaying the protein fragments to T cells, which become activated when they recognize one of the antigens.

—Daniel M. Davis

… antigen-presenting cells also display fragments of proteins derived from the body's own cells. In this case, the antigen-presenting cells train the T cells to ignore healthy cells that are part of the body.

—Denise Faustman

—abbreviation APC

Examples of antigen-presenting cell in a Sentence

Recent Examples on the Web

Inflammation may activate more antigen-presenting cells (APCs) than usual.2 ACPs are immune cells that help fight off infections.15 Does Exercise Boost Your Immune System? —Jenny McCoy, Health, 7 Sep. 2023

Word History

First Known Use

1975, in the meaning defined above

Medical Definition

antigen-presenting cell

noun

: any of various cells (as a dendritic cell, macrophage, or B cell) that take up and process an antigen into a peptide fragment which when displayed at the cell surface in combination with histocompatibility antigen is recognized by and serves to activate cells of the immune system (as helper T cells or cytotoxic T cells)

In contrast to antibody molecules, which can bind to antigens in solution, T cell receptors recognize antigen only when it is displayed on the surface of an antigen-presenting cell in association with a major histocompatibility complex (MHC) antigen.

—Scientific American Medicine Bulletin

—abbreviation APC