Inherited genetic disorders of the liver pose a significant public health burden. Liver transplantation is often limited by the availability of donor livers and the exorbitant costs of immunosuppressive therapy. To overcome these limitations, nucleic acid therapy provides a hopeful alternative that enables gene repair, gene supplementation, and gene silencing with suitable vectors. Though viral vectors are the most efficient and preferred for gene therapy, pre-existing immunity debilitating immune responses limit their use. As a potential alternative, lipid nanoparticle-mediated vectors are being explored to deliver multiple nucleic acid forms, including pDNA, mRNA, siRNA, and proteins. Herein, we discuss the broader applications of lipid nanoparticles, from protein replacement therapy to restoring the disease mechanism through nucleic acid delivery and gene editing, as well as multiple preclinical and clinical studies as a potential alternative to liver transplantation.
Epidermal knockout of integrin β1 results in complete disorganization of the basement membrane (BM), resulting in neonatal lethality. Here, we report that this disorganization is exacerbated by an early embryonic inflammatory response involving the recruitment of tissue-resident and monocyte-derived macrophages to the dermal-epidermal junction, associated with increased matrix metalloproteinase activity. Remarkably, the skin barrier in the integrin β1 knockout animals is intact, suggesting that this inflammatory response is initiated in a sterile environment. We demonstrate that the molecular mechanism involves de novo expression of integrin αvβ6 in the basal epidermal cells, which activates a TGF-β1 driven inflammatory cascade resulting in upregulation of dermal NF-κB in a Tenascin C-dependent manner. Importantly, treatment of β1 KO embryos in utero with small molecule inhibitors of TGF-βR1 and NF-κB results in marked rescue of the BM defects and amelioration of immune response, revealing an unconventional immuno-protective role for integrin β1 during BM remodeling.
Cationic lipid-guided nucleic acid delivery holds great promise in gene therapy and genome-editing applications for treating genetic diseases. However, the major challenge lies in achieving therapeutically relevant efficiencies. Prior findings, including our own, demonstrated that asymmetry in the hydrophobic core of cationic lipids imparted superior transfection efficiencies. To this end, we have developed a lipid nanocarrier system with an asymmetric hydrophobic core (PS-Lips) derived from a mixture of fatty acids of food-grade palmstearin and compared its efficiency with symmetric palmitic acid-based nanocarrier system (P-Lip). PS-Lips exhibited superior transfection efficiencies with both plasmid DNA (pDNA) and mRNA in multiple cultured cells than the control P-Lip. More importantly, PS-Lips exhibited 2-fold superior transfections with linear nucleic acid, green fluorescent protein (GFP) mRNA in hematopoietic cells, when compared with the commercial control lipofectamine RNAiMAX. PS-Lips was also found to be effective in delivering genome-editing tools (CRISPR/Cas9, sgRNA encoded pDNA with a reporter GFP construct) than P-Lip in HEK-293 cells. In the present study, we report that cationic liposomes derivatized from natural food-grade fat palmstearin with a natural hydrophobic core asymmetry are efficient in delivering both linear and circular nucleic acids. In particular, PS-Lips is efficient in delivering mRNA to hematopoietic cells. These findings can be further exploited in the genome-editing approach for treating β-globinopathies.
The continual emergence of SARS-CoV-2 variants has necessitated the development of broad cross-reactive vaccines. Recent findings suggest that enhanced antigen presentation could lead to cross-reactive humoral responses against the emerging variants. Towards enhancing the antigen presentation to dendritic cells (DCs), we developed a novel shikimoylated mannose receptor targeting lipid nanoparticle system (SMART-LNPs) that could effectively deliver mRNAs into DCs. To improve the translation of mRNA, we developed spike domain-based trimeric-S1 (TS1) mRNA with optimized codon sequence, base modification, and engineered 5'&3' UTRs. In a mouse model, SMART-LNPs-TS1 vaccine could elicit robust broad cross-reactive IgGs against Omicron sub-variants, and induced IFNγ producing T-cells against SARS-CoV-2 virus compared to non-targeted LNPs-TS1 vaccine. Further, T-cells analysis revealed that SMART-LNPs-TS1 vaccine induced long-lived memory T-cell subsets, Th1-dominant and cytotoxic T-cells immune responses against SARS-CoV-2 virus. Importantly, SMART-LNPs-TS1 vaccine produced strong Th1-predominant humoral and cellular immune responses. Overall, SMART-LNPs can be explored for precise antigenic mRNA delivery and robust immune responses. This platform technology can be explored further as a next-gen delivery system for mRNA-based immune therapies.