Differential glycosylation of TH1, TH2 and TH-17 effector cells selectively regulates susceptibility to cell death

Regulated glycosylation controls T cell processes, including activation, differentiation and homing by creating or masking ligands for endogenous lectins. Here we show that stimuli promoting T helper type 1 (T(H)1), T(H)2 or interleukin 17-producing T helper (T-H-17) differentiation can differentially regulate the glycosylation pattern of T helper cells and modulate their susceptibility to galectin-1, a glycan-binding protein with anti-inflammatory activity. Although T(H)1- and T-H-17-differentiated cells expressed the repertoire of cell surface glycans critical for galectin-1-induced cell death, T(H)2 cells were protected from galectin-1 through differential sialylation of cell surface glycoproteins. Consistent with those findings, galectin-1-deficient mice developed greater T(H)1 and T-H-17 responses and enhanced susceptibility to autoimmune neuroinflammation. Our findings identify a molecular link among differential glycosylation of T helper cells, susceptibility to cell death and termination of the inflammatory response.