Author Archives: Geoff Symonds

Figure 1: A cell-delivered gene therapy process begins with (1) apheresis, in which granulocyte colony stimulating factor (G-CSF) is administered to stimulate production of stem cells and their release into blood. Small-volume apheresis is taken for CD4+ T-cell isolation, and larger volumes are taken for CD34+ hematopoietic stem progenitor cells (HSPCs). After (2) a cell isolation step to purify the desired cell populations (T cells or HSPCs), purified cells are transduced with a therapeutic lentiviral vector (3). Following harvest of transduced T cells and HSPCs (4), modified cells are collected and cryopreserved. Finally (5), genetically modified autologous cells are transplanted back to the same patient. Busulfan chemotherapy is administered before transplantation to create “space” in the patient’s bone marrow for the therapeutically modified cells.

Cell-Delivered Gene Therapy: This Viral Vector Manufacturing Method Could Widen Its Applicability

Cell-delivered gene therapy is making an impact on a range of diseases (1–17). To date, successful treatments have generally been in conditions involving genetic deficiencies/abnormalities, for which introduction of a normal gene allele has been corrective (1–12, 18). Such an approach requires a vector containing the normal allele to overcome the mutant or lacking gene. The vector of choice for cell-delivered gene therapy is often a lentivirus that integrates and expresses introduced therapeutic genes in host target cells and their…