In this preclinical study, we evaluated the efficacy and feasibility of creating broad human immunodeficiency virus (HIV) resistance by simultaneously disrupting the human CCR5 and CXCR4 genes, which encode cellular co-receptors required for HIV-1 infection. Using a clinically scalable system for transient ex vivo delivery of Cas9/guide RNA (gRNA) ribonucleoprotein (RNP) complexes, we demonstrated that CRISPR-mediated disruption of CCR5 and CXCR4 in T lymphocyte cells significantly reduced surface expression of the co-receptors, thereby establishing resistance to HIV-1 infection by CCR5 (R5)-tropic, CXCR4 (X4)-tropic, and dual (R5/X4)-tropic strains. Similarly, disruption of CCR5 alleles in human CD34+ hematopoietic stem and progenitor cells (HSPCs) successfully led to the differentiation of HIV-resistant macrophages. In a humanized mouse model under HIV-1 challenge, CXCR4-disrupted CD4+ T cells were enriched in the peripheral blood and spleen, indicating survival advantage because of resistance to viral infection. However, in human CD4+ T cells with both CCR5 and CXCR4 disruption, we observed poor engraftment in bone marrow, although significant changes were not observed in the lung, spleen, or peripheral blood. This study establishes a clinically scalable strategy for the dual knockout of HIV-1 co-receptors as a therapeutic strategy, while also raising caution of disrupting CXCR4, which may abate engraftment of CD4+ T cells in bone marrow.
Keywords: CCR5; CRISPR; CXCR4; HIV; T cells; adoptive T cell therapy; bone marrow; gene editing; macrophage.
© 2022 The Authors.