Phagocytosis at a glance.

Abstract

Phagocytosis functions as the internalisation mechanism responsible for engulfing large particles, microorganisms and cellular debris. It relies on specific cell surface receptors to induce membrane deformation, extension and contraction for particle engulfment. The actin cytoskeleton provides the necessary force for membrane deformation, whereas intracellular compartments aid in membrane reshaping and signal coordination. Following internalisation within a sealed compartment, the phagosome undergoes fusion and fission processes, ultimately forming a phagolysosome, where degradation takes place. Finally, a resolution step enables the recycling and reuse of soluble elements and membranes. This scavenging process is essential for feeding in single-celled eukaryotes and plays a crucial role in maintaining tissue homeostasis and regulating immune responses in higher eukaryotes.