Regulatory T cell expressing a chimeric antigen receptor

A combination of pharmaceutical compositions comprising

• i) a population of human Treg cells expressing a CAR together with a pharmaceutical acceptable carrier, the CAR comprising
• a) at least one antigen binding domain,
• b) a transmembrane domain,
• c) a cytoplasmic signaling domain comprising at least one primary cytoplasmic signaling domain and at least the co-stimulatory signaling domain of CD137, wherein said at least one antigen binding domain specifically binds dextran;
• and
• ii) a dextran molecule that is not conjugated to an antibody or another attachment structure which allows specific targeting of the dextran to cells or tissue matrix surfaces in vivo,
• thereby allowing the activation of said Treg cell upon binding of dextran to said at least one antigen binding domain of said CAR.