Inhibition of Human Immunodeficiency Virus Type 1 Replication in Myelomonocytic Cells Derived from Retroviral Vector-Transduced Peripheral Blood Progenitor Cells

Abstract

Monocytes and macrophages (Mo/MΦ) contribute to the pathogenesis of human immunodeficiency virus type 1 (HIV-1) infection. A successful hematopoietic stem/progenitor cell (HSPC)-based gene therapy strategy for HIV-1 disease must protect Mo/MΦ as well as T cells from HIV-1-related pathology. In this report, we demonstrate that RevM10-transduced HSPCs isolated from cytokine-mobilized peripheral blood give rise to Mo/MΦ suppressing replication of MΦ-tropic HIV-1 isolates. A Moloney murine leukemia virus (MoMLV)-based retroviral vector encoding a bicistronic mRNA co-expressing RevM10 and the murine CD8α′ chain (Lyt2) was used to transduce HSPCs. Following transduction, these cells were expanded and differentiated by short-term culture in methylcellulose containing various cytokines. In vitro differentiated Mo/MΦ were enriched by fluorescence activated cell sorting (FACS) for the co-expressed transgene (Lyt2) and myelomonocytic (CD33, CD14) surface markers. HIV-1 replication of two MΦ-tropic isolates (JR-FL, BaL) was inhibited in Mo/MΦ expressing RevM10 and Lyt2 relative to control cells expressing only Lyt2 but no functional RevM10 gene product. Cell proliferation and expression of lineage-specific surface markers was not altered in transduced, in vitro differentiated Mo/MΦ cells. This study supports the feasibility of HSPC-based gene therapy as a future treatment for HIV-1 disease.

Overview summary

Inhibition of human immunodeficiency virus Type 1 (HIV-1) replication in myeloid cells derived from hematopoietic stem/progenitor cells (HSPCs) is critical for the success of stem cell-based gene therapy for HIV-1 disease. In this study, replication of two macrophage-tropic HIV-1 isolates was inhibited by expression of the trans-dominant RevM10 mutant in myeloid cells derived from retrovirally transduced cytokine-mobilized peripheral blood CD34⁺ cells. Furthermore, expression of the RevM10 mutant protein did not alter cellular expansion and surface marker expression of myeloid cells. In summary, this preclinical study supports the feasibility of stem cell-based gene therapy in the myeloid lineage for the treatment HIV-1 disease.