Lentivirus-mediated Gene Transfer in Hematopoietic Stem Cells Is Impaired in SHIV-infected, ART-treated Nonhuman Primates

• Published in: Molecular therapy Vol. 23; no. 5; pp. 943 - 951
• Main Authors: Younan, Patrick M, Peterson, Christopher W, Polacino, Patricia, Kowalski, John P, Obenza, Willimark, Miller, Hannah W, Milless, Brian P, Gafken, Phil, DeRosa, Stephen C, Hu, Shiu-Lok, Kiem, Hans-Peter
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.05.2015; Elsevier Limited; Nature Publishing Group
• Subjects: Acquired immune deficiency syndrome; AIDS; Animals; Antiretroviral Therapy, Highly Active; Cancer research; Chemokines; Drug therapy; Gene Expression; Gene therapy; Genetic Therapy; Genetic Vectors - genetics; Hematopoietic Stem Cell Transplantation; Hematopoietic Stem Cells - metabolism; HIV; Human immunodeficiency virus; Immunophenotyping; Infections; Lentivirus - genetics; Leukemia; Lymphocyte Count; Lymphoma; Macaca; Macaca nemestrina; Medical research; Original; Patients; Plasma; Research centers; Simian Acquired Immunodeficiency Syndrome - immunology; Simian Acquired Immunodeficiency Syndrome - therapy; Simian Acquired Immunodeficiency Syndrome - virology; Simian Immunodeficiency Virus - immunology; Simian/human immunodeficiency virus; Stem cells; T-Lymphocyte Subsets - immunology; T-Lymphocyte Subsets - radiation effects; T-Lymphocyte Subsets - virology; Transduction, Genetic; Transgenes; Transplantation Conditioning; Transplants & implants; Vectors (Biology); Viral Load; United States > US
• ISSN: 1525-0016; 1525-0024
• DOI: 10.1038/mt.2015.19

Recent studies have demonstrated that genetically modified hematopoietic stem cells (HSCs) can reduce HIV viremia. We have developed an HIV/AIDS-patient model in Simian/human immunodeficiency virus (SHIV)-infected pigtailed macaques that are stably suppressed on antiretroviral therapy (ART: raltegravir, emtricitabine and tenofovir). Following SHIV infection and ART, animals undergo autologous HSC transplantation (HSCT) with lentivirally transduced cluster of differentiation (CD)34+ cells expressing the mC46 anti-HIV fusion protein. We show that SHIV+, ART-treated animals had very low gene marking levels after HSCT. Pretransduction CD34+ cells contained detectable levels of all three ART drugs, likely contributing to the low gene transfer efficiency. Following HSCT recovery and the cessation of ART, plasma viremia rebounded, indicating that myeloablative total body irradiation cannot completely eliminate viral reservoirs after autologous HSCT. The kinetics of recovery following autologous HSCT in SHIV+, ART-treated macaques paralleled those observed following transplantation of control animals. However, T-cell subset analyses demonstrated a high percentage of C-C chemokine receptor 5 (CCR5)-expressing CD4+ T-cells after HSCT. These data suggest that an extended ART interruption time may be required for more efficient lentiviral transduction. To avoid complications associated with ART interruption in the context of high percentages of CD4+CCR5+T-cells after HSCT, the use of vector systems not impaired by the presence of residual ART may also be beneficial.