Therapeutic Effects of Hematopoietic Stem Cell Derived From Gene-Edited Mice on β654-Thalassemia.

β-thalassemia is an inherited blood disease caused by reduced or inadequate β-globin synthesis due to β-globin gene mutation. Our previous study developed a gene-edited mice model (β654-ER mice) by CRISPR/Cas9-mediated genome editing, targeting both the βIVS2-654 (C > T) mutation site and the 3' splicing acceptor site at 579 and corrected abnormal β-globin mRNA splicing in the β654-thalassemia mice. Herein, we further explored the therapeutic effect of the hematopoietic stem cells (HSCs) from β654-ER mice on β-thalassemia by consecutive HSC transplantation. The results indicated that HSC transplantation derived from gene-edited mice can significantly improve the survival rate of mice after lethal radiation doses and effectively achieve hematopoietic reconstruction and long-term hematopoiesis. Clinical symptoms, including hematologic parameters and tissue pathology of transplanted recipients, were significantly improved compared to the non-transplanted β654 mice. The therapeutic effect of gene-edited HSC transplantation demonstrated no significant difference in hematological parameters and tissue pathology compared with wild-type mouse-derived HSCs. Our data revealed that HSC transplantation from gene-edited mice completely recovered the β-thalassemia phenotype. Our study systematically investigated the therapeutic effect of HSCs derived from β654-ER mice on β-thalassemia and further confirmed the efficacy of our gene-editing approach. Altogether, it provided a reference and primary experimental data for the clinical usage of such gene-edited HSCs in the future.