Antigen-Presenting Cell (APC)

A type of cell that collects foreign materials (antigens), digests them into small pieces, and "displays" or "presents" the pieces on its surface. Other cells of the immune system recognize these pieces and become activated to fight the foreign invader. APCs include B lymphoctyes, macrophages, and dendritic cells.
See Also: B Lymphocytes, Macrophage, Dendritic Cells, Antigen
  

The cell type that collects foreign material (antigen, see) and digests it into pieces that can be recognized by the immune system. The APC presents the antigen to the helper T cells<!-- (see) -->, the CD4+ T cells; this results in the initiation of expansion of an immune response targeted against the foreign material. APCs are B cells, macrophages, or dendritic cells (see entries for these terms).