Definition: Heterophagy is the process of lysosomal digestion of materials ingested from the extracellular environment. Extracellular materials are taken up by cells through the general process of endocytosis.

Uptake of particulate matter is known as phagocytosis; uptake of soluble smaller macromolecules is called pinocytosis.

Extracellular materials are endocytosed into vacuoles (endosomes or phagosomes), which eventually fuse with lysosomes to form phagolysosomes, where the engulfed material is digested. Heterophagy is most common in the "professional" phagocytes, such as neutrophils and macrophages, although it may also occur in other cell types.

Examples of heterophagocytosis include the uptake and digestion of bacteria by neutrophils and the removal of apoptotic cells by macrophages.

See also

 phagocytosis

References

 Ravichandran KS: "Recruitment signals" from apoptotic cells: invitation to a quiet meal. Cell 113:817, 2003. PMID: #12837239#