Emperipolesis is the presence of an intact cell within the cytoplasm of another cell.[1] It is derived from Greek (en is inside, peripoleomai is go round).[2] Emperipolesis is an uncommon biological process, and can be physiological or pathological.[3]
It is related to peripolesis, which is the attachment of one cell to another.[4]
Emperipolesis is unlike phagocytosis, in which the engulfed cell is killed by the lysosomal enzymes of the macrophage. Instead, the engulfed cell remains viable within the other, and can exit at any time without causing structural or functional abnormalities in either cell.[3]