Abstract: Described herein are methods for genetically modifying expanded hematopoietic cells comprising obtaining a quantity of hematopoietic cells, culturing the quantity of hematopoietic cells in the presence of at least one histone deacetylase inhibitor (HDACi) and at least one growth factor to expand the hematopoietic cells, and contacting the expanded hematopoietic cells with a nucleic acid sequence, wherein the nucleic acid sequence modifies the quantity of expanded hematopoietic cells. Further described herein are compositions comprising the genetically modified hematopoietic cells produced by these methods.

Abstract: Described herein are methods and compositions which lead to the efficient ex vivo expansion of hematopoietic cells, such as hematopoietic stem cells (HSCs) and hematopoietic stem and progenitor cells HSPCs. Using combinations of small molecule drugs and cytokines/growth factors/grown factors targeting epigenetic status in cells, significant improvements in the expansion of cells was observed, including cells isolated from human cord blood or peripheral mobilized stem/progenitor cells. Multiple genes implicated in HSPC function were unperturbed, and efficiency of genomic editing using lentivirus was greatly enhanced following treatment. These novel approaches could be used therapeutically in a variety of hematopoietic transplantation settings, in addition to benefiting gene therapy techniques.