Editing an ?-globin enhancer in primary human hematopoietic stem cells as a treatment for ?-thalassemia.

ABSTRACT: ?-Thalassemia is one of the most common inherited anemias, with no effective cure for most patients. The pathophysiology reflects an imbalance between ?- and ?-globin chains with an excess of free ?-globin chains causing ineffective erythropoiesis and hemolysis. When ?-thalassemia is co-inherited with ?-thalassemia, excess free ?-globin chains are reduced significantly ameliorating the clinical severity. Here we demonstrate the use of CRISPR/Cas9 genome editing of primary human hematopoietic stem/progenitor (CD34+) cells to emulate a natural mutation, which deletes the MCS-R2 ?-globin enhancer and causes ?-thalassemia. When edited CD34+ cells are differentiated into erythroid cells, we observe the expected reduction in ?-globin expression and a correction of the pathologic globin chain imbalance in cells from patients with ?-thalassemia. Xenograft assays show that a proportion of the edited CD34+ cells are long-term repopulating hematopoietic stem cells, demonstrating the potential of this approach for translation into a therapy for ?-thalassemia.?-thalassemia is characterised by the presence of an excess of ?-globin chains, which contribute to erythrocyte pathology. Here the authors use CRISP/Cas9 to reduce ?-globin expression in hematopoietic precursors, and show effectiveness in xenograft assays in mice.

SUBMITTER: Mettananda S 

PROVIDER: S-EPMC5583283 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature