aAflac Cancer and Blood Disorders Center, Children's Healthcare of Atlanta and Department of Pediatrics, Emory University, Pediatric Hematopoietic Cellular Therapy

bAflac Cancer and Blood Disorders Center, Children's Healthcare of Atlanta and Department of Pediatrics, Pediatric Hematology, Emory University, Atlanta, Georgia

cBoston Children's/Dana Farber Cancer and Blood Disorders Center, Pediatric Hematopoietic Cellular Therapies, Boston, Massachusetts, USA

Correspondence to Michelle Schoettler, MD, 1760 Haygood Drive, 3rd floor W423, Atlanta, GA 30322, USA. Tel: +1 404 727 5381; e-mail: [email protected]