Details

Autor(en) / Beteiligte

• Newby, Gregory A
• Yen, Jonathan S
• Woodard, Kaitly J
• Mayuranathan, Thiyagaraj
• Lazzarotto, Cicera R
• Li, Yichao
• Sheppard-Tillman, Heather
• Porter, Shaina N
• Yao, Yu
• Mayberry, Kalin
• Everette, Kelcee A
• Jang, Yoonjeong
• Podracky, Christopher J
• Thaman, Elizabeth
• Lechauve, Christophe
• Sharma, Akshay
• Henderson, Jordana M
• Richter, Michelle F
• Zhao, Kevin T
• Miller, Shannon M
• Wang, Tina
• Koblan, Luke W
• McCaffrey, Anton P
• Tisdale, John F
• Kalfa, Theodosia A
• Pruett-Miller, Shondra M
• Tsai, Shengdar Q
• Weiss, Mitchell J
• Liu, David R

Titel

Base editing of haematopoietic stem cells rescues sickle cell disease in mice

Ist Teil von

• Nature (London), 2021-07, Vol.595 (7866), p.295-302

Ort / Verlag

England: Nature Publishing Group

Erscheinungsjahr

2021

Link zum Volltext

Quelle

MEDLINE

Beschreibungen/Notizen

• Sickle cell disease (SCD) is caused by a mutation in the β-globin gene HBB . We used a custom adenine base editor (ABE8e-NRCH) to convert the SCD allele (HBB ) into Makassar β-globin (HBB ), a non-pathogenic variant . Ex vivo delivery of mRNA encoding the base editor with a targeting guide RNA into haematopoietic stem and progenitor cells (HSPCs) from patients with SCD resulted in 80% conversion of HBB to HBB . Sixteen weeks after transplantation of edited human HSPCs into immunodeficient mice, the frequency of HBB was 68% and hypoxia-induced sickling of bone marrow reticulocytes had decreased fivefold, indicating durable gene editing. To assess the physiological effects of HBB base editing, we delivered ABE8e-NRCH and guide RNA into HSPCs from a humanized SCD mouse and then transplanted these cells into irradiated mice. After sixteen weeks, Makassar β-globin represented 79% of β-globin protein in blood, and hypoxia-induced sickling was reduced threefold. Mice that received base-edited HSPCs showed near-normal haematological parameters and reduced splenic pathology compared to mice that received unedited cells. Secondary transplantation of edited bone marrow confirmed that the gene editing was durable in long-term haematopoietic stem cells and showed that HBB -to-HBB editing of 20% or more is sufficient for phenotypic rescue. Base editing of human HSPCs avoided the p53 activation and larger deletions that have been observed following Cas9 nuclease treatment. These findings point towards a one-time autologous treatment for SCD that eliminates pathogenic HBB , generates benign HBB , and minimizes the undesired consequences of double-strand DNA breaks.