Exocytosis of macrophage lysosomes leads to digestion of apoptotic adipocytes and foam cell formation.

ABSTRACT: Many types of apoptotic cells are phagocytosed and digested by macrophages. Adipocytes can be hundreds of times larger than macrophages, so they are too large to be digested by conventional phagocytic processes. The nature of the interaction between macrophages and apoptotic adipocytes has not been studied in detail. We describe a cellular process, termed exophagy, that is important for macrophage clearance of dead adipocytes and adipose tissue homeostasis. Using mouse models of obesity, human tissue, and a cell culture model, we show that macrophages form hydrolytic extracellular compartments at points of contact with dead adipocytes using local actin polymerization. These compartments are acidic and contain lysosomal enzymes delivered by exocytosis. Uptake and complete degradation of adi

SUBMITTER: Haka AS 

PROVIDER: S-EPMC4878183 | biostudies-literature | 2016 Jun

REPOSITORIES: biostudies-literature