Autophagy and autoimmunity

Autophagy is a lysosomal degradation mechanism in eukaryotic organisms and has a crucial role in cell homeostasis by controlling organelles and proteins turnover and sustaining survival in cellular stress conditions such as nutrients deprivation. Cytoplasmic material, sequestered within characteristic double-membrane vesicles, known as autophagosomes, is degraded into autophagolysosome to recycle components for energy supply. Recently, the Nobel Prize assigned to the Japanese biologist Yoshinori Ohsumi for his studies on molecular mechanism of autophagy in yeast, brought to light the importance of the process as a therapeutic target in human diseases. In this regard, autophagy was found to be dysregulated in several disorders, such as cancer and neurodegeneration, as well as in other diseases. Moreover, immune system development and function appeared to be strictly linked to autophagy activation. Autophagy orchestrates innate and adaptive immune responses to intracellular pathogens and contributes to MHC class II-mediated presentation of intracellular antigens to CD4+ T lymphocytes [4]. Indeed, B and T lymphocytes, key players in autoimmune diseases pathogenesis, seem to be particularly dependent on autophagy for their development, survival, and proliferation. Starting from these considerations, interesting data on the role of autophagy in the pathogenesis of autoimmune diseases were obtained, suggesting a treatment intervention based on autophagy modulation. In this chapter, we analyze only the role of macroautophagy (autophagy) in autoimmune diseases.