Description
The importance of regulatory T cells (Treg) for immune tolerance is well recognized, yet the signaling molecules influencing their suppressive activity are relatively poorly understood. We identified the cytoplasmic tyrosine phosphatase SHP-1 as a novel endogenous brake and modifier of the suppressive ability of Treg cells; consistent with this notion, loss of SHP-1 expression strongly augments the ability of Treg cells to suppress inflammation in a mouse model. Specific harmacological inhibition of SHP-1 enzymatic activity via the cancer drug sodium stibogluconate (SSG) potently augmented Treg cell suppressor activity both in vivo and ex vivo.