Autophagy in Antigen Presentation

Macroautophagy (hereafter referred to as autophagy) is a eukaryotic catabolic pathway that eliminates intracellular contents and thereby provides cells with a source of nutrients. This fundamental pathway of cellular degradation also participates in immunity and inflammation. The capacity of autophagy to traffic, and to degrade, cytosolic protein is exploited by immune cells as a means to elicit antigen presentation. Here, we will summarize the current knowledge about the intersection of both classical and non-canonical autophagy with pathways of antigen presentation. While the role of autophagy in major histocompatibility complex class II (MHC II) presentation is well documented, autophagy is also implicated in endogenous MHC I presentation and MHC I cross-presentation. Thus, autophagy is a major effector of antigen presentation and has the capacity to impact host immunity and tolerance.