67. The Chicken Hypersensitive Site (cHS4) Insulator Element Reduces Position Effects Thereby Increasing Expression from Globin Lentiviral Vectors

Abstract

Lentiviral vectors (LV) carrying the human β-globin gene (hβ) and locus control region (LCR) have changed the field of gene therapy for hemoglobinopathies. However, their random integration into host cells results in variable hβ expression from chromatin position effects. We analyzed the role of a 1.2 kb chicken β-globin locus hypersensitive site 4 insulator element (cHS4) in a self-inactivating (SIN) LV. The BGM vector (carrying hβ/LCR) was compared to an analogous vector BGMI, with cHS4 such that it flanks the provirus upon integration.