863. Expression and Secretion of Human Glucocerebrosidase Mediated by Recombinant Lentivirus Vectors In Vitro and In Vivo

Abstract

Listen

Translate article

Gaucher disease is a lysosomal storage disorder resulting from a deficiency of glucocerebrosidase (GC). Most research on gene therapy for Gaucher disease has centered on ex vivo transduction of hematopoietic stem cells by retroviral vectors. In this study, we showed that vascular and hepatic delivery of a HIV-1 based recombinant lentivirus vector encoding human GC cDNA produced therapeutic levels of GC protein.Human cell lines and Gaucher fibroblasts were transduced at 10-50 multiplicity of infection (MOI) of lenti-EF-GC or lenti-CMV-GC. In vivo experiments were carried out in C57BL/6J mice by intravenous and intraportal injection with 1-5 107 transducing unit (TU) of lenti-EF-GC. Cells and tissues were assayed for GC activity. A high level of expression of GC was produced in cultured fibroblasts derived from patients with Gaucher disease by transducing the cells with lentivirus vectors. GC secreted by transduced fibroblasts was taken up by adjacent GC-deficient cells by endocytosis. Intraportal administration of recombinant lenti-EF-GC vector was resulted in efficient transduction of hepatic cells and expression of the GC. Vascular delivery of vector resulted in high levels of GC expression in liver, spleen, heart, lung, and bone marrow cells in mice that persisted in most organs over the four months. No significant abnormalities were found attributable to recombinant lentivirus vectors in any of the tissues examined. Recombinant lentivirus vector-mediated gene transfer appears to be effective and safe. This study represents an initial step toward gene transfer using recombinant lentivirus vectors for treatment of Gaucher disease.