In vivo killing of primary HIV-infected cells by peripheral-injected early memory–enriched anti-HIV duoCAR T cells

Abstract

HIV-specific chimeric antigen receptor–T cell (CAR T cell) therapies are candidates to functionally cure HIV infection in people with HIV (PWH) by eliminating reactivated HIV-infected cells derived from latently infected cells within the HIV reservoir. Paramount to translating such therapeutic candidates successfully into the clinic will require anti-HIV CAR T cells to localize to lymphoid tissues in the body and eliminate reactivated HIV-infected cells such as CD4 + T cells and monocytes/macrophages. Here we show that i.v. injected anti-HIV duoCAR T cells, generated using a clinical-grade anti-HIV duoCAR lentiviral vector, localized to the site of active HIV infection in the spleen of humanized mice and eliminated HIV-infected PBMCs. CyTOF analysis of preinfusion duoCAR T cells revealed an early memory phenotype composed predominantly of CCR7 + stem cell–like/central memory T cells (T SCM /T CM ) with expression of some effector-like molecules. In addition, we show that anti-HIV duoCAR T cells effectively sense and kill HIV-infected CD4 + T cells and monocytes/macrophages. Furthermore, we demonstrate efficient genetic modification of T cells from PWH on suppressive ART into anti-HIV duoCAR T cells that subsequently kill autologous PBMCs superinfected with HIV. These studies support the safety and efficacy of anti-HIV duoCAR T cell therapy in our presently open phase I/IIa clinical trial (NCT04648046).

Harnessing immune cells to eliminate HIV reservoirs

“…This supports an earlier report that HIV-infected macrophages are susceptible to HIV-specific CAR T cells [65]. Recently, duo CAR T cells, which are created using autologous T cells transduced with two CAR constructs (mD1.22-CAR and m36.4-CAR), eliminated HIV-infected splenic PBMCs of humanized mice, along with infected CD4 + T cells and monocytes in vitro [82 ▪▪ ]. These are currently being tested in a Phase I/IIa clinical trial in PLWH (NCT04648046).…”

Challenges in HIV-1 Latent Reservoir and Target Cell Quantification in CAR-T Cell and Other Lentiviral Gene Modifying HIV Cure Strategies

“…In addition, these variable domains fall victim to the same shortcomings that their parent monoclonal and bNAbs faced, an inability to accurately target the gp120 protein. A current study is using lentiviral vectors to mediate CAR-modification of T cells to present these anti-HIV CARs (i.e., duoCARs) and make cells resistant to HIV-1 [ 41 , 67 ]. Other novel CAR-T-cell technologies are being developed to recognize, bind, and kill MHC–antigen complexes, but these methods are predominantly in the pre-clinical development stage for various malignancies [ 15 , 16 , 17 , 18 , 19 ].…”

“…Lentiviral-based gene modification is used to generate CAR-T cells for HIV-1 cure in patients who are otherwise healthy and stably suppressed on ART (ClinicalTrials.gov #NCT04648046) [ 41 , 67 ]. While the cells transduced with lentiviral vectors make RNA transcripts that code for CARs or other products of interest in gene therapy studies, they are engineered to avoid lentiviral replication [ 79 , 121 ].…”

Strategies to target the central nervous system HIV reservoir

“…Of note, macrophages are particularly hard to be targeted by the host CD8 + T-cells [74], and may resist killing while maintaining inflammatory functions [75]. Interestingly, recent data in vitro showed that this resistance to cell death in macrophages may not be maintained against CAR-T cells [75,76 ▪▪ ], despite the low env antigen density on the surface of those cells [77]. Nonetheless, in vivo data are still lacking, and whether these findings also apply to brain-resident microglia is still unknown.…”