Fig. 3
From: Metabolic programming in dendritic cells tailors immune responses and homeostasis
Metabolic regulation of antigen cross-presentation. Antigen cross-presentation requires uptake of extracellular antigen by either receptor-mediated endocytosis or phagocytosis. NADPH oxidase 2 (NOX2) is the major cellular ROS source, and it also maintains an alkaline pH in the early phagosome, which reduces antigen degradation, retaining antigen-peptide for MHC-I loading. Antigens are subsequently transferred to the cytosol and processed by proteasomal degradation before being loaded to MHC-I and presented on the cell surface. As an inhibitor of autophagy, mTORC1 reduces endogenous antigen uptake. Cross-presentation is supported by mitochondria driven by kinases Mst1/Mst2
