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bioRxiv · 10.1101/2020.10.13.338319

Cas9-AAV6 Gene Correction of Beta-Globin in Autologous HSCs Improves Sickle Cell Disease Erythropoiesis in Mice

Abstract

CRISPR/Cas9-mediated beta-globin (HBB) gene correction of Sickle Cell Disease (SCD) patient-derived hematopoietic stem cells (HSCs) in combination with autologous transplantation represents a novel paradigm in gene therapy. Although several Cas9-based HBB-correction approaches have been proposed, functional correction of in vivo erythropoiesis has not been investigated. Here, we used a humanized globin-cluster SCD mouse model to study Cas9-AAV6-mediated HBB-correction in functional HSCs within the context of autologous transplantation. We discover that long-term multipotent HSCs can be gene corrected ex vivo and stable hemoglobin-A production can be achieved in vivo from HBB-corrected HSCs following autologous transplantation. We observed a direct correlation between increased HBB-corrected myeloid chimerism and normalized in vivo RBC features, but even low levels of chimerism resulted in robust hemoglobin-A levels. Moreover, this study offers a platform for gene editing of mouse HSCs for both basic and translational research.

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Wilkinson, A. C., Dever, D. P., Baik, R., Camarena, J., Hsu, I., Charlesworth, C. T., Morita, C., Nakauchi, H., Porteus, M. H.. 2020-10-13. Cas9-AAV6 Gene Correction of Beta-Globin in Autologous HSCs Improves Sickle Cell Disease Erythropoiesis in Mice. https://doi.org/10.1101/2020.10.13.338319

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