Figure 1

Cell-delivered gene therapy strategies using autologous CD34+ hematopoietic stem cells (HSCs). Human immunodeficiency virus (HIV) patients are treated with granulocyte colony-stimulating factor (G-CSF) to mobilize HSCs before collection (step 1). Primary blood mononuclear cells (PBMCs) are harvested by large-volume apheresis and HSCs are selected and purified (steps 2–3). HSCs are transduced with the anti-HIV gene therapy vector and infused back into the patient (steps 4 and 5b). Although not performed in the Mitsuyasu et al.¹ trial, patients may receive bone marrow conditioning by chemotherapy and/or radiotherapy to potentially increase the efficiency of engraftment (step 5a).