21. EpoR expression can extend as far back as the hematopoietic stem cell compartment. 22. It has also been attributed to an inhibitory activity on hematopoietic progenitor cells. 23. Sickle hemoglobin induces the expression of heme oxygenase-1 in hematopoietic cells. 24. MTORC1 plays a role in the differentiation and proliferation of hematopoietic stem cells. 25. Its upregulation has been shown to cause premature aging in hematopoietic stem cells. 26. They form a scaffold for hematopoietic cells and assist their movement along it. 27. Factors influencing B lymphopoiesis after allogeneic hematopoietic cell transplantation. 28. Yet, expanding hematopoietic stem cells has proven a particularly elusive goal for scientists. 29. Some even refer to expansion as the holy grail of hematopoietic stem cell work. 30. This has only been studied in patients who previously underwent hematopoietic stem cell transplantation.
