Acknowledgements
The authors thank all of the physicians and staff at the hospital and the cord blood bank in Japan for their help in this study. This work was supported in part by grants-in-aid from Japanese Society for the Promotion of Science (JSPS), and Takeda Science Foundation.
Potential conflict of interest
Disclosure forms provided by the authors are available with the full text of this article online at http://dx.doi.org/10.1080/10428194.2017.1318440.