Tumor-Tailored Ionizable Lipid Nanoparticles Facilitate IL-12 Circular RNA Delivery for Enhanced Lung Cancer Immunotherapy.

The advancement of message RNA (mRNA) -based immunotherapies for cancer is highly dependent on the effective delivery of RNA (Ribonucleic) payloads using ionizable lipid nanoparticles (LNPs). However, the clinical application of these therapies is hindered by variable mRNA expression among different cancer types and the risk of systemic toxicity. The transient expression profile of mRNA further complicates this issue, necessitating frequent dosing and thus increasing the potential for adverse effects. Addressing these challenges, a high-throughput combinatorial method is utilized to synthesize and screen LNPs that efficiently deliver circular RNA (circRNA) to lung tumors. The lead LNP, H1L1A1B3, demonstrates a fourfold increase in circRNA transfection efficiency in lung cancer cells over ALC-0315, the industry-standard LNPs, while providing potent immune activation. A single intratumoral injection of H1L1A1B3 LNPs, loaded with circRNA encoding interleukin-12 (IL-12), induces a robust immune response in a Lewis lung carcinoma model, leading to marked tumor regression. Immunological profiling of treated tumors reveals substantial increments in CD45+ leukocytes and enhances infiltration of CD8+ T cells, underscoring the ability of H1L1A1B3 LNPs to modulate the tumor microenvironment favorably. These results highlight the potential of tailored LNP platforms to advance RNA drug delivery for cancer therapy, broadening the prospects for RNA immunotherapeutics.

An elastase-inhibiting, plaque-targeting and neutrophil-hitchhiking liposome against atherosclerosis.

Neutrophil extracellular traps (NETs) play a crucial role in the formation of vulnerable plaques and the development of atherosclerosis. Alleviating the pathological process of atherosclerosis by efficiently targeting neutrophils and inhibiting the activity of neutrophil elastase to inhibit NETs is relatively unexplored and is considered a novel therapeutic strategy with clinical significance. Sivelestat (SVT) is a second-generation competitive inhibitor of neutrophil elastase with high specificity. However, therapeutic effect of SVT on atherosclerosis is restricted because of the poor half-life and the lack of specific targeting. In this study, we construct a plaque-targeting and neutrophil-hitchhiking liposome (cRGD-SVT-Lipo) to improve the efficacy of SVT in vivo by modifying the cRGD peptide onto SVT loaded liposome, which was based on the interaction between cRGD peptide and integrin ανß3 on the surface of cells in blood and plaque, including epithelial cell, macrophage and neutrophils. The cRGD-SVT-Lipo could actively tend to or hitchhike neutrophils in situ to reach atherosclerotic plaque, which resulted in enhanced atherosclerotic plaque delivery. The cRGD-SVT-Lipo could also reduce plaque area, stabilize plaque, and ultimately alleviate atherosclerosis progression through efficiently inhibiting the activity of neutrophil elastase in atherosclerotic plaque. Therefore, this study provides a basis and targeting strategy for the treatment of neutrophil-related diseases. STATEMENT OF SIGNIFICANCE: Neutrophil extracellular traps (NETs)-inhibiting is a prospective therapeutic approach for atherosclerosis but has received little attention. The NETs can be inhibited by elastase-restraining. In this work, an intriguing system that delivers Sivelestat (SVT), a predominantly used neutrophil elastase inhibitor with poor targeting capability, is designed to provide the drug with plaque-targeting and neutrophil-hitchhiking capability. The result suggests that this system can effectively hinder the formation of NETs and delay the progression of atherosclerosis.

Nano-sponge-like liposomes remove cholesterol crystals for antiatherosclerosis.

Atherosclerotic cardiovascular diseases remain the leading causes of morbidity and mortality worldwide. Cholesterol crystals in atherosclerotic plaques play an essential role in atherosclerosis progression. However, no clinical drugs have been used for removing cholesterol crystals from plaque to counter atherosclerosis. Previous studies identified the hydrophobic domain of lipid bilayer in liposomes acted as sinks for solubilizing hydrophobic cholesterol. Moreover, adjusting the composition of the lipid bilayer in liposomes can enhance its hydrophobic molecule loading capacity. Therefore, in this study, ginsenosides Rb1 (Rb1), one of main active components of ginseng which has a similar structure to cholesterol, is anchored into soy phospholipids bilayer with its hydrophobic region to prepare nano-sponge-like liposomes (Rb1-LPs), aiming to amplify the solubilization of cholesterol in lipid bilayer. For targeting delivery to atherosclerotic plaques, Annexin V (AnxV), a protein that can specifically recognize phosphatidylserine upregulated in atherosclerotic plaques, is applied to decorate the surface of Rb1-LPs by click reaction to obtain the final preparation of AnxV-Rb1-LPs. The in vitro studies showed that incorporating Rb1 into lipid bilayer remarkably increased the affinity of the lipid bilayer to free cholesterol and the solubilization of cholesterol crystals. Additionally, nano-sponge-like liposomes could efficiently reduce the accumulation of cholesterol crystals and improve cholesterol efflux, finally inhibiting inflammation and apoptosis in cholesterol-laden cells. Furthermore, AnxV-Rb1-LPs could efficiently accumulate in atherosclerotic plaques after intravenous injection, exert nano-sponge-like functions to remove intra- and extracellular cholesterol crystals, ultimately alleviating inflammation and apoptosis in atherosclerotic plaques for antiatherosclerosis. Therefore, AnxV-Rb1-LPs provide a potential strategy for removing cholesterol crystals in atherosclerotic plaques and can be further utilized in other diseases with excessive cholesterol accumulation.

The Impaired Mechanism and Facilitated Therapies of Efferocytosis in Atherosclerosis.

ABSTRACT: Cardiovascular disease is responsible for the largest number of deaths worldwide, and atherosclerosis is the primary cause. Apoptotic cell accumulation in atherosclerotic plaques leads to necrotic core formation and plaque rupture. Emerging findings show that the progression of atherosclerosis appears to suppress the elimination of apoptotic cells. Mechanistically, the reduced edibility of apoptotic cells, insufficient phagocytic capacity of phagocytes, downregulation of bridging molecules, and dysfunction in the polarization of macrophages lead to impaired efferocytosis in atherosclerotic plaques. This review focuses on the characteristics of efferocytosis in plaques and the therapeutic strategies aimed at promoting efferocytosis in atherosclerosis, which would provide novel insights for the development of antiatherosclerotic drugs based on efferocytosis.

Poly-ß-cyclodextrin Supramolecular Nanoassembly with a pH-Sensitive Switch Removing Lysosomal Cholesterol Crystals for Antiatherosclerosis.

Cholesterol crystals (CCs), originally accumulating in the lysosome of cholesterol-laden cells, can aggravate the progression of atherosclerosis. ß-cyclodextrin (CD) is a potent cholesterol acceptor or CC solubilizer. However, the random extraction of cholesterol impedes the in vivo application of CD for removing lysosomal CCs. Here, we exploit poly-ß-cyclodextrin (pCD) as a lysosomal CC solubilizer and dextran sulfate grafted with benzimidazole (BM) as a pH-sensitive switch (pBM) to self-assemble into a supramolecular nanoassembly (pCD/pBM-SNA). The CD cavity in pCD/pBM-SNA can be efficiently sealed by hydrophobic BM at pH 7.4 (OFF). After it enters the lysosome, pCD/pBM-SNA disassembles, recovers the CD cavity to dissolve CCs into free cholesterol due to the protonation of BM (ON), and reduces CCs, finally enhancing the cholesterol efflux and promoting atherosclerosis regression. Our findings provide an "OFF-ON" tactic to remove lysosomal CCs for antiatherosclerosis as well as other diseases such as Niemann-Pick type C diseases with excessive cholesterol accumulation in the lysosome.