1. From the Fraunhofer Institute for Cell Therapy and Immunology, Leipzig, Germany (D.-C.W., C.P., I.S., G.S., J.B., F.L., J.S., K.M., G.W.); Translational Centre for Regenerative Medicine, University of Leipzig, Leipzig, Germany (D.-C.W., J.B., G.W.); and Stroke and Neurovascular Regulation Laboratory, Massachusetts General Hospital, Harvard Medical School, Boston, MA (J.B.).