IFN‐γ‐primed platelets enriched with immunosuppressive ligands (PD‐L1, PD‐L2, BTLA, and Gal‐9) are shown to induce T cell exhaustion and apoptosis, preserving β‐cell function and preventing hyperglycemia progression in type 1 diabetes. Here, IFNG is linked to type 1 diabetes mellitus.