Oxidative Stress in Antigen Processing and Presentation

ABSTRACT Antigen processing and presentation are fundamental for connecting innate and adaptive immune responses in combating cancers and infections. Reactive oxygen species (ROS), serving as second messengers in various physiological processes, play a vital role in modulating antigen processing and presentation. However, oxidative stress due to an imbalance characterized by excessive accumulation of ROS or inadequate antioxidant defenses can severely impair antigen‐specific immune responses, contributing to the pathophysiology of multiple health conditions, notably including various cancers, cancer‐associated infections and autoimmune diseases. This review comprehensively investigates the multifaceted effects of ROS on antigen processing and presentation, encompassing immunopeptide generation, the functionality of antigen‐presentation machinery (APM), and the interactions of antigen‐presenting cells and antigen‐specific effector cells. It emphasizes the critical pathophysiological roles of oxidative stress in diseases such as cancers, cancer‐associated infections and autoimmune diseases. Moreover, we delve into the therapeutic potential of targeting redox homeostasis to enhance antitumor immune responses. By illuminating the intricate interplay between ROS and immune functionality, this review provides an essential theoretical framework for developing innovative immunotherapy strategies aimed at restoring immune competency and improving clinical outcomes in patients with immune‐related diseases.