Thymosin alpha 1: the regulator of regulators?

The peripheral immune system can promote either immunity or tolerance when presented with new antigens. Current knowledge withholds that populations of suppressor or regulatory T cells (T-reg cells) constitute a pivotal mechanism of immunological tolerance. The potential role of malfunctioning T-reg cells in chronic inflammatory immune and autoimmune diseases is well-documented. Learning how to successfully manipulate T-reg responses could result in more effective vaccines and immunomodulators. We have already shown that Thymosin alpha 1 (T alpha 1), a naturally occurring thymic peptide first described and characterized by Allan Goldstein in 1972, by modulating signals delivered through innate immune receptors on dendritic cells, affects adaptive immune responses via modulation of Th cell effector and regulatory functions. We will discuss recent molecular mechanisms underlying the ability of T alpha 1 to activate or inhibit immune responses.