Glutathione supersulphide regulates T-cell receptor signalling
Immunometabolism regulates functions and fates of immune cells including T cells. Supersulphides, which are universal metabolites containing catenated sulphur atoms, have various physiological functions based on their unique redox properties. Here we found that activation of T-cell receptor (TCR) signalling was accompanied by supersulphide decrease, which suggests a regulatory contribution of sulphur metabolism to immune function. Consistently, inhibiting supersulphide synthesis facilitated TCR activation and exacerbated allergen-induced type 2 inflammation in mice. Supplementation with glutathione trisulphide (GSSSG), a major endogenous supersulphide, suppressed TCR signalling in naive CD4+ T cells and their differentiation and effectively alleviated the inflammation. Docking simulation revealed interaction of GSSSG with CD3{varepsilon} chain in the TCR/CD3 complex, which was supported by mass spectrometry detection of persulphidated glutathionylation at a functionally important CXXC motif of CD3{varepsilon} chain. This study identified a new post-translational modification with supersulfides and demonstrated a critical contribution of sulphur metabolism to TCR signalling regulation.