1 Department of Anatomy and Physiology, Midwest Institute for Comparative Stem Cell Biology, Kansas State University, Manhattan, KS 66506, USA.
2 The New York Stem Cell Foundation, New York, NY 10023, USA.
3 Rubius Therapeutics, Cambridge, MA 02139, USA.
4 Institute of Bioprocess Engineering and Pharmaceutical Technology, University of Applied Sciences Mittelhessen, 35390 Giessen, Germany; Faculty of Biology and Chemistry, Justus Liebig University Giessen, 35390 Giessen, Germany.