Ex vivo editing of human hematopoietic stem cells for erythroid expression of therapeutic proteins

Giulia Pavani (1, 2) , Marine Laurent (1, 2) , Anna Fabiano (1, 2) , Erika Cantelli (1, 2) , Aboud Sakkal (1, 2) , Guillaume Corre (1, 2) , Peter J. Lenting (3) , Jean-Paul Concordet (4) , Magali Toueille (1) , Annarita Miccio (5) , Mario Amendola (1, 2)

1 Généthon
2 INTEGRARE - Approches génétiques intégrées et nouvelles thérapies pour les maladies rares
3 HITH - U1176 Inserm - CHU Bicêtre - Hémostase, Inflammation, Thrombose
4 STRING - Structure et Instabilité des Génomes
5 Chromatin and gene regulation during development

Targeted genome editing has a great therapeutic potential to treat disorders that require protein replacement therapy. To develop a platform independent of specific patient mutations, therapeutic transgenes can be inserted in a safe and highly transcribed locus to maximize protein expression. Here, we describe an ex vivo editing approach to achieve efficient gene targeting in human hematopoietic stem/progenitor cells (HSPCs) and robust expression of clinically relevant proteins by the erythroid lineage. Using CRISPR-Cas9, we integrate different transgenes under the transcriptional control of the endogenous α-globin promoter, recapitulating its high and erythroid-specific expression. Erythroblasts derived from targeted HSPCs secrete different therapeutic proteins, which retain enzymatic activity and cross-correct patients' cells. Moreover, modified HSPCs maintain long-term repopulation and multilineage differentiation potential in transplanted mice. Overall, we establish a safe and versatile CRISPR-Cas9-based HSPC platform for different therapeutic applications, including hemophilia and inherited metabolic disorders.

Domains: Molecular biology; Hematology

Giulia Pavani, Marine Laurent, Anna Fabiano, Erika Cantelli, Aboud Sakkal, et al.. Ex vivo editing of human hematopoietic stem cells for erythroid expression of therapeutic proteins. Nature Communications, 2020, 11 (1), pp.3778. ⟨10.1038/s41467-020-17552-3⟩. ⟨inserm-02946890⟩