Systemic activation of antigen-presenting cells via RNA-loaded nanoparticles

Abstract

While RNA-pulsed dendritic cell (DC) vaccines have shown promise, the advancement of cellular therapeutics is fraught with developmental challenges. To circumvent the challenges of cellular immunotherapeutics, we developed clinically translatable nanoliposomes that can be combined with tumor-derived RNA to generate personalized tumor RNA-nanoparticles (NPs) with considerable scale-up capacity. RNA-NPs bypass MHC restriction, are amenable to central distribution, and can provide near immediate immune induction.We screened commercially available nanoliposomal preparations and identified the cationic lipid 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) as an efficient mRNA courier to antigen-presenting cells (APCs). When administered intravenously, RNA-NPs mediate systemic activation of APCs in reticuloendothelial organs such as the spleen, liver, and bone marrow. RNA-NPs increase percent expression of MHC class I/II, B7 co-stimulatory molecules, and maturation markers on APCs (all vital for T-cell activation). RNA-NPs also increase activation markers on tumor APCs and elicit potent expansion of antigen-specific T-cells superior to peptide vaccines formulated in complete Freund's adjuvant. We demonstrate that both model antigen-encoding and physiologically-relevant tumor-derived RNA-NPs expand potent antitumor T-cell immunity. RNA-NPs were shown to induce antitumor efficacy in a vaccine model and functioned as a suitable alternative to DCs in a stringent cellular immunotherapy model for a radiation/temozolomide resistant invasive murine high-grade glioma.Although cancer vaccines have suffered from weak immunogenicity, we have advanced a RNA-NP formulation that systemically activates host APCs precipitating activated T-cell frequencies necessary to engender antitumor efficacy. RNA-NPs can thus be harnessed as a more feasible and effective immunotherapy to re-program host-immunity.

Broadening the Message: A Nanovaccine Co-loaded with Messenger RNA and α-GalCer Induces Antitumor Immunity through Conventional and Natural Killer T Cells

“…This study reports on a nanoparticle platform, named mRNA Galsomes, that successfully co-delivers nucleoside-modified antigen-encoding mRNA and the glycolipid antigen and immunopotentiator α-Galactosylceramide (α-GC) to antigen-presenting cells after Where for long the use of mRNA was limited due to its perceived instability, it is nowadays possible to successfully deliver mRNA in vivo. 1 This is strongly supported by two recent breakthroughs: (i) the packaging of mRNA molecules inside nanoparticles, designed to improve the selective cell targeting and cytosolic delivery of mRNA [2][3][4][5][6][7][8][9] and (ii) the technical progress in the mRNA construct, including the incorporation of modified nucleotides, yielding more stable mRNA with an improved translation capacity. [10][11][12][13] Particularly in the field of vaccination, mRNA encoding antigens has emerged as a versatile and promising platform.…”

Total tumor RNA pulsed dendritic cells plus adoptive transfer of ex-vivo enriched autologous T-lymphocytes in the treatment of children with primary brain tumors

“…Whether such optimization of fecal microbiome in patients receiving ALT will prove beneficial remains be evaluated. Using NGS methodology and HLA-typing to improve prediction of MHC-I class and MHC-II class binding epitopes to create a robust neoantigen predominant transcriptome for electroporation into DCs [47] , nanoparticle vaccines [109] , and/or the use of immune checkpoint inhibitors [30,110] are other potential strategies to enhance efficacy in an adjuvant setting or relapse following x-ALT + ttRNA DCs. With these refinements and more this form of ACT promises to be an important therapeutic approach in the management of pediatric brain tumors.…”

Nanomedicines to Deliver mRNA: State of the Art and Future Perspectives

“…This mixture facilitates the endosomal escape under acidic pH conditions, thanks to the capacity of DOPE to modify the lipoplex from a bilayer model to hexagonal phase II (H II ) structures, known to induce supramolecular arrangements which result in the fusion of lipid bilayers [7,95]. The use of DOTAP alone or in combination with the helper lipid DOPE has been applied to mRNA delivery [96,97]. More recently, ionizable lipids with lower toxicity, but preserving the transfection capacity, such as 1,2-dioleoyl-3-dimethylammonium propane (DODAP) or 1,2-dioleyloxy-N,N-dimethyl-3-aminopropane (DODMA), have been developed as an alternative to conventional cationic lipids [5].…”