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Biology subjects

Dhole, P.

Publications and source records attributed to Dhole, P..

4 recordsLinked to original sources

Co-delivered PD-L1 rescues the protective efficacy mediated by an AAV-expressed HIV-1 bNAb

Adeno-associated virus (AAV)-delivered anti-HIV-1 broadly neutralizing antibodies (bNAbs) could prevent and treat HIV-1 infection but are limited by host immune responses, specifically anti-drug antibodies (ADA). We tested whether PD-L1-mediated immune shielding could improve the consistency of AAV-delivered bNAb expression from muscle tissue in rhesus macaques. AAV9.PD-L1 co-delivery with AAV9.3BNC117 reduced the occurrence of ADA and T cell responses and improved the durability of 3BNC117 expression for one year post administration. Importantly, 5 of 6 macaques that received co-delivered AAV9.PD-L1 vectors were protected against ten repeated SHIVAD8-EO challenges. Histopathological and spatial transcriptomic profiling showed that AAV9.PD-L1 co-delivery prevented severe local inflammation, muscle injury, and tertiary lymphoid structure formation at the administration site. Thus, immune shielding could serve as a strategy to prolong transgene expression from muscle-directed AAV-delivered biologics.

immunology↗

Overcoming host immune responses to an AAV-delivered HIV-1 bNAb in rhesus macaques mediated by co-delivery of PD-L1

Adeno-associated virus (AAV)-delivered anti-HIV-1 broadly neutralizing antibodies (bNAbs) have demonstrated promise for preventing and treating HIV-1 infection in preclinical models. However, host immune responses, specifically anti-drug antibodies (ADA), limit sustained bNAb expression. We have previously shown that PD-L1-mediated immune shielding improves the consistency of AAV-delivered bNAb 3BNC117 expression from muscle tissue in rhesus macaques. Here, we test the breadth of this approach with another bNAb, 10-1074. We show that AAV9.PD-L1 co-delivery with AAV9.10-1074 reduced the occurrence of ADA responses and improved the durability of bNAb expression for one year post administration. Notably 12 of 12 macaques that received AAV9.10-1074 vectors were protected against ten repeated SHIVAD8-EO challenges. Histopathological profiling showed that AAV9.PD-L1 co-delivery prevented severe local inflammation and tertiary lymphoid structure formation at the administration site. Thus, immune shielding could serve as a broad strategy to prolong transgene expression from muscle-directed AAV-delivered biologics.

immunology↗

Characterization of expression elements for an AAV delivered antibody in nonhuman primates when co-delivered with PD-L1

Successful AAV-expressed antibody therapy for HIV-1 requires broadly neutralizing antibody (bNAbs) concentrations and reduced immune responses to sustain viral suppression without ART. We have previously demonstrated that co-delivery of AAV-expressed PD-L1 reduces immune responses against HIV-1 bNAbs in rhesus macaques. Here we systematically evaluated six AAV9 transgene cassettes encoding 10-1074 with different promoter/intron combinations (CMV, CMV/R, CBA, CASI, CB7, EF1) across in vitro systems, immune-deficient mice, and in rhesus macaques. We show that both promoter and species selection, leads to differences in 10-1074 concentrations with the CB7 promoter leading to greatest expression in mice and CMV/R promoter in macaques. In addition to differences observed, loss of 10-1074 serum concentrations in macaques resulted in higher anti-drug antibody responses and antigen specific IFN-y T cell responses were focused on the 10-1074 heavy-chain variable region. Furthermore, inclusion of the WPRE greatly impacted 10-1074 expression leading to higher concentrations in both mice and nonhuman primates. Lastly, circulating 10-1074 in macaques retained neutralizing activity against diverse HIV-1 pseudovirus isolates. Together these results demonstrate how expression elements influence AAV-expressed antibodies in the context of co-delivery and highlight the need for further improvements to AAV transgene cassettes when co-delivered with AAV expressed PD-L1.

microbiology↗

Delivery of defective interfering RNA antivirals to the lungs using hyperbranched poly(beta-amino ester) nanoparticles

Hyperbranched poly(beta-amino ester) (hPBAE) nanoparticles represent a promising platform for nucleic acid delivery, particularly to the lungs. In this study, we evaluate the potential of hPBAE nanoparticles to deliver defective interfering RNA (diRNA) antivirals targeting betacoronaviruses under a range of formulations and storage conditions. hPBAE-diRNA nanoparticles demonstrated efficient cellular uptake of functional diRNA across diverse cell types, conferred protection against nuclease-mediated degradation, and exhibited low in vitro cytotoxicity. In vivo, these nanoparticles enabled effective delivery of functional diRNA to the lungs of golden hamsters without inducing adverse physiological effects. Collectively, these findings support hPBAE nanoparticles as a safe and effective platform for diRNA delivery for the treatment of respiratory viral infections. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=66 SRC="FIGDIR/small/721911v1_ufig1.gif" ALT="Figure 1"> View larger version (19K): org.highwire.dtl.DTLVardef@2fc386org.highwire.dtl.DTLVardef@1cda4f9org.highwire.dtl.DTLVardef@9f61borg.highwire.dtl.DTLVardef@1fc8461_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphical Abstract.C_FLOATNO Defective interfering RNA was mixed with hyperbranched poly(beta-amino ester) nanoparticles and delivered to cells in vitro and to golden hamsters in vivo, to measure toxicity and the replication potential of the RNA. C_FIG

microbiology↗