Allorecognition
![Movie generated from tracings of gastrovascular canals (red) in two colonies of Hydractinia symbiolongicarpus that come into contact and then separate. The green structures are polyps.](/Images/godic/202412/19/-Allorecognition-Triggers-Autophagy-and-Subsequent-Necrosis-in-the-Cnidarian-Hydractinia-pone.0048914.s004.ogv0920.jpg")
Allorecognition is the ability of an individual organism to distinguish its own tissues from those of another. It manifests itself in the recognition of antigens expressed on the surface of cells of non-self origin. Allorecognition has been described in nearly all multicellular phyla.