Notably, even at the lowest dose used, representing a 1:20 EngTreg to input PBMC ratio, A2CAR EngTreg still displayed partial efficacy in blocking GvHD disease progression (Figures 5B–5D, comparing the purple and blue groups), indicating the potency of the Ag-specific suppression conveyed by the A2CAR in this model. Here, RENBP is linked to graft versus host disease.