Fig. 1
From: Strategies for immune regulation in iPS cell-based cardiac regenerative medicine
Mechanisms of immunosuppression induced by Treg. a Treg establishes immune tolerance by inhibiting the activation and proliferation of immune cells that cause immune rejection. In addition, the high sensitivity of IL-2 causes Treg to selectively proliferate and increases the Treg population. b IL-2 is a cytokine essential for T cell differentiation, proliferation, and maintenance and binds to IL-2R; IL-2 is more likely to bind in the presence of CD25; Treg expresses high levels of CD25; Treg reduces the expression of CD80/86 in antigen-presenting cells. In addition, Treg suppresses the CD80/86 co-stimulation to T cells as a result of the high expression of CTLA-4, which is prone to bind CD80/86