About the Authors

Desirée L. Salazar

Current address: Department of Cellular and Molecular Medicine, Ludwig Institute for Cancer Research, University of California San Diego, La Jolla, California, United States of America

Affiliations Department of Anatomy and Neurobiology, University of California Irvine, Irvine, California, United States of America, Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, California, United States of America, Reeve-Irvine Research Center, University of California Irvine, Irvine, California, United States of America

Nobuko Uchida

Affiliation StemCells, Inc., Palo Alto, California, United States of America

Frank P. T. Hamers

Affiliation Rehabilitation Hospital Tolbrug, 's Hertogenbosch, The Netherlands

Brian J. Cummings

Contributed equally to this work with: Brian J. Cummings, Aileen J. Anderson

Affiliations Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, California, United States of America, Reeve-Irvine Research Center, University of California Irvine, Irvine, California, United States of America, Department of Physical Medicine and Rehabilitation, University of California Irvine, Irvine, California United States of America

Aileen J. Anderson

Contributed equally to this work with: Brian J. Cummings, Aileen J. Anderson

aja@uci.edu

Affiliations Department of Anatomy and Neurobiology, University of California Irvine, Irvine, California, United States of America, Sue and Bill Gross Stem Cell Research Center, University of California Irvine, Irvine, California, United States of America, Reeve-Irvine Research Center, University of California Irvine, Irvine, California, United States of America, Department of Physical Medicine and Rehabilitation, University of California Irvine, Irvine, California United States of America

Competing Interests

Nobuko Uchida is a paid employee of StemCells, Inc. Aileen J. Anderson has served as a paid consultant to StemCells, Inc. This does not alter the authors' adherence to all the PLoS ONE policies on sharing data and materials.

Author Contributions

Conceived and designed the experiments: DLS NU BJC AJA. Performed the experiments: DLS BJC. Analyzed the data: DLS BJC AJA. Contributed reagents/materials/analysis tools: NU FPTH. Wrote the paper: DLS BJC AJA.