Pharmacological activation of nitric oxide signaling promotes human hematopoietic stem cell homing and engraftment

Hematopoietic cell transplantation (HCT), dependent on hematopoietic stem cells (HSC), is widely used for treatment of many hematological and non-hematological disorders 1 .Successful clinical outcome of HCT predominantly relies on adequate homing and longterm engraftment of HSC into the bone marrow (BM).Enhancing the efficacy of HSC homing and engraftment could have a relevant impact on improving HCT and patient survival, especially when limiting numbers of HSCs are available, as in using umbilical cord blood (CB) or poorly mobilized peripheral blood 2-4 .Although efforts have been devoted to developing potential means to enhance HSC engraftment, including boosting HSC expansion 5,6 , enhancing HSC homing 7, 8 , mitigating Extra Physiologic Oxygen Shock/ Stress (EPHOSS) 9 or generating HSCs by reprogramming 10, 11 , it is not yet clear which