Cellular Immune Tolerance

Cellular Immune Tolerance is a sophisticated regulatory mechanism employed by the immune system to maintain self-tolerance and prevent autoimmune responses against the body's own tissues. Unlike central tolerance, which occurs during T cell development in the thymus, cellular immune tolerance operates in the periphery and involves various mechanisms to suppress or regulate immune responses to self-antigens that may be encountered in peripheral tissues. One key mechanism of cellular immune tolerance is peripheral tolerance induction, which involves the suppression or deletion of auto reactive T cells in the periphery to prevent their activation and subsequent autoimmune reactions. Regulatory T cells (Tregs) play a central role in maintaining peripheral tolerance by suppressing the activation and function of auto reactive T cells through cell-cell contact or the secretion of immunosuppressive cytokines such as interleukin-10 (IL-10) and transforming growth factor-beta (TGF-β). Another important mechanism of cellular immune tolerance is peripheral energy, which refers to the functional inactivation of self-reactive T cells upon encounter with self-antigens in the absence of co-stimulatory signals. In the absence of adequate co-stimulation, T cells fail to become fully activated and enter a state of unresponsiveness or energy, preventing them from mounting an immune response against self-antigens.