The commentary by Ralph M. Steinman, Shannon Turley, Ira Mellman, and Kayo Inaba discusses the role of dendritic cells (DCs) in inducing tolerance to self-antigens, particularly in the context of capturing apoptotic cells. DCs play a crucial role in maturation, which is essential for their immunogenicity. Maturation changes DCs in several ways, including the expression of costimulatory molecules, production of cytokines, and redistribution of MHC class II molecules. The authors argue that DCs are essential for inducing peripheral tolerance, which is necessary to prevent autoreactivity and immune responses to self-tissues. They propose that immature DCs, which traffic through tissues and phagocytose apoptotic cells, induce tolerance by presenting these antigens to T cells in lymph nodes. This process involves the transfer of apoptotic bodies from migratory DCs to longer-lived, tolerogenic DCs in lymph nodes, where they form high levels of MHC-II complexes and induce T cell anergy or deletion. The authors conclude that DCs are specialized to control immunity and maintain tolerance, and that the maturation of peripheral DCs allows them to focus on foreign antigens during infection.The commentary by Ralph M. Steinman, Shannon Turley, Ira Mellman, and Kayo Inaba discusses the role of dendritic cells (DCs) in inducing tolerance to self-antigens, particularly in the context of capturing apoptotic cells. DCs play a crucial role in maturation, which is essential for their immunogenicity. Maturation changes DCs in several ways, including the expression of costimulatory molecules, production of cytokines, and redistribution of MHC class II molecules. The authors argue that DCs are essential for inducing peripheral tolerance, which is necessary to prevent autoreactivity and immune responses to self-tissues. They propose that immature DCs, which traffic through tissues and phagocytose apoptotic cells, induce tolerance by presenting these antigens to T cells in lymph nodes. This process involves the transfer of apoptotic bodies from migratory DCs to longer-lived, tolerogenic DCs in lymph nodes, where they form high levels of MHC-II complexes and induce T cell anergy or deletion. The authors conclude that DCs are specialized to control immunity and maintain tolerance, and that the maturation of peripheral DCs allows them to focus on foreign antigens during infection.