Targeted lipid nanoparticles for gene therapeutics delivery approach to eradicating HIV reservoirs

Abstract The direct elimination of integrated replication silent human immunodeficiency virus type one (HIV-1) proviral DNA has not been achieved in an infected human host. A pathway toward success rests in surgical delivery to tissues and cell viral reservoirs. We posit that this can be realized through optimal viral suppression (by ultra- long-acting antiretrovirals, ULA ARV) coupled with tissue-cell targeted lipid nanoparticles (LNPs) for CD4+ T and myeloid cell delivery and enhancements of viral excision efficacy. Our goals are to suppress, target, deliver, and then eliminate integrated proviral DNA in target cells and tissue reservoirs by a novel delivery platform. This platform will be optimized in HIV-1 infected cells and then in infected animals (H. Gendelman). We will achieve maximal viral suppression by ULA ARV (B. Edagwa). The viral cell and tissue reservoirs targeting will be achieved by compositionally unique CRISPR-Cas9 and guide RNA (gRNA) encased LNP (CRISPR LNP) formulation (S. Panja). The brain delivery of CRISPR LNP will be achieved by microbubble- enhanced focused ultrasound (FUS) (L. Chang). With this objective in mind, we will optimize the LNP composition to achieve lymphoid tissue-specific biodistribution. The biodistribution will be accessed by radiomagnetic labeling of LNP using positron emission tomography and magnetic resonance imaging (MRI) bioimaging (Y. Liu). We will build on the tissue-specific LNP and establish a tissue and cell reserve targeted CRISPR LNP by decorating with C- X-C chemokine receptor type 4 (CXCR4) and/or C-C motif chemokine receptor 5 (CCR5) targeting ligands. FUS will ensure the CRISPR LNP biodistribution, most notably to the central nervous system. The research, taken together, seeks to determine how, where, and to what extent the viral editing CRISPR cargo will reach its destination (i.e., lymph nodes, gut, spleen, and brain). Therefore, we now have the tools in place for therapeutic viral excision to precisely eliminate integrated latent HIV-1 from the host genome (P. Dash and S. Gorantla). Our multi-exon gRNAs recognize a broad swath of viral strains, and CRISPR LNPs can bypass the viral vector delivery and eliminate induced immunogenicity and consequent toxicity. We posit that viral suppression by combinations of ULA ARV followed by tissue-cell targeted delivery of CRISPR cargos can achieve viral “elimination” in live infected mice. The cross-disciplinary LNP delivery platform will ensure the efficacy, safety, and rigor of HIV-1 viral elimination approaches.