Footnotes

• Contributors DK contributed to acquiring the data, imaging analysis, drafting and revising the manuscript for intellectual content and final approval. JS funded the trial and provided the stem cells. JM contributed to imaging data acquisition. FM and XH contributed to clinical reviews and data acquisition. KWM contributed to study design, critically revising the manuscript and final approval.

• Funding ReNeuron Ltd. funded the PISCES study.

• Competing interests DK has received Jim Gatheral and MacRobertson travel scholarship and Guarantors of Brain travel scholarships. JS is an employee and stock holder of ReNeuron Ltd. KWM has received trial funding from ReNeuron for PISCES and PISCES-2 stroke stem cell trial.

• Patient consent for publication Not required.

• Ethics approval National Research Ethics Committee (Formerly Gene Therapy Advisory Committee, UK).

• Provenance and peer review Not commissioned; externally peer reviewed.