Autophagy in autoimmunity

Autophagy comprises a number of evolutionary conserved catabolic pathways that were originally described to transport assigned cargo to the endolysosomal system in order to maintain metabolic integrity and homeostasis. More recently, autophagy pathways have also been recognized for orchestrating physiological and pathological immune responses via limiting the intracellular proliferation of pathogens, restricting the secretion of proinflammatory mediators and by directing T-cell responses. Autophagy-mediated antigen processing in thymic epithelial cells contributes to the generation of a self-MHC restricted and self-tolerant CD4⁺ T-cell repertoire. In experimental models of autoimmune diseases, components of the autophagy machinery are reported to both accelerate and ameliorate clinical disease development. Here, we provide an introduction to autophagy as an innate immune defense mechanism, highlight its supporting role in the initiation and execution of adaptive immune responses, and discuss its function in the development of autoimmune tissue inflammation.