The novel mechanism of peripheral tolerance

Phagocytosis of apoptotic cells and immune regulation

The termination of the apoptotic programme occurs in most cases via recognition and clearance by phagocytes, especially the professional phagocytes, such as macrophages and immature dendritic cells. Engulfed cells do not simply disappear from the midst of living tissues. The fine-defined presentation of yielded self-antigens to T cells is a central event in the induction or the maintenance of the peripheral immune tolerance to self. Conversely, abnormality in this pathway may contribute to the pathogenesis of systemic and organ-specific autoimmune diseases. We herein reviewed the relationship between phagocytosis of apoptotic cells and immune regulation, especially the effects of engulfed apoptotic cells on immune tolerance and autoimmune diseases.