https://doi.org/10.1351/goldbook.12888
Cell, such as a dendritic cell or macrophage, that is responsible for making antigens accessible to lymphocytes and other immune effector and regulatory cells, making possible specific recognition by receptors on the cell surface.
Note: In a more restricted way, used to describe major histocompatibility complex (MHC) class II-positive cells (accessory cells) that internalize and degrade an antigen (generally by phagocytosis), before a fragment of the antigen molecule is presented on the APC cell surface in association with an MHC molecule. This complex is recognized by either B cells via surface-bound immunoglobulin (Ig) molecules, or by T cells via the T-cell receptor (TCR) for the antigen. Induction of a specific immune response then proceeds.