LC3-Associated Phagocytosis and Antigen Presentation

LC3-associated phagocytosis (LAP) is an unconventional form of autophagy that relies on parts of the canonical autophagy machinery for its function. LAP is triggered upon receptor-mediated phagocytosis and is characterized by the formation of a single-membrane vesicle decorated with the autophagy protein LC3. In professional phagocytic cells, such as macrophages, the role of LAP in immune processes has been characterized, although how LAP functions at the molecular level remains poorly defined. It is important to point out that as for all autophagic pathways, the study of LAP is still challenging for the scientific community because it is a dynamic and complex process, requiring interactions among several proteins. Here, we describe the most common methods used to monitor and quantify the formation of LC3-coated single-membrane endosomes, or so-called LAPosomes, and to validate the involvement of LAP in immunological processes of human macrophages.