Abstract: The present invention provides an engineered regulatory T cell (Treg) comprising a chimeric antigen receptor (CAR) for use in induction of tolerance to a transplant; treating and/or preventing graft-versus-host disease (GvHD), an autoimmune or allergic disease; to promote tissue repair and/or tissue regeneration; or to ameliorate chronic inflammation secondary to metabolic disorders; wherein the CAR comprises an endodomain which comprises a STAT association motif and a JAK1- and/or a JAK2-binding motif.