Mesenchymal stromal cells as vehicles of tetravalent bispecific Tandab (CD3/CD19) for the treatment of B cell lymphoma combined with IDO pathway inhibitor D-1-methyl-tryptophan.

Background Although blinatumomab, a bispecific T cell engaging antibody, exhibits high clinical response rates in patients with relapsed or refractory B-precursor acute lymphoblastic leukemia (B-ALL) and B cell non-Hodgkin’s lymphoma (B-NHL), it still has some limitations because of its short half-life. Mesenchymal stromal cells (MSCs) represent an attractive approach for delivery of therapeutic agents to cancer sites owing to their tropism towards tumors, but their immunosuppression capabilities, especially induced by indoleamine 2,3-dioxygenase (IDO), should also be taken into consideration.