In vivo endothelial siRNA delivery using polymeric nanoparticles with low molecular weight

Recent Progress in Nucleic Acid Pulmonary Delivery toward Overcoming Physiological Barriers and Improving Transfection Efficiency

Pulmonary delivery of therapeutic agents has been considered the desirable administration route for local lung disease treatment. As the latest generation of therapeutic agents, nucleic acid has been gradually developed as gene therapy for local diseases such as asthma, chronic obstructive pulmonary diseases, and lung fibrosis. The features of nucleic acid, specific physiological structure, and pathophysiological barriers of the respiratory tract have strongly affected the delivery efficiency and pulmonary bioavailability of nucleic acid, directly related to the treatment outcomes. The development of pharmaceutics and material science provides the potential for highly effective pulmonary medicine delivery. In this review, the key factors and barriers are first introduced that affect the pulmonary delivery and bioavailability of nucleic acids. The advanced inhaled materials for nucleic acid delivery are further summarized. The recent progress of platform designs for improving the pulmonary delivery efficiency of nucleic acids and their therapeutic outcomes have been systematically analyzed, with the application and the perspectives of advanced vectors for pulmonary gene delivery.

Nucleic acids based integrated macromolecular complexes for SiRNA delivery: Recent advancements

The therapeutic potential of small interfering RNA (siRNA) is monumental, offering a pathway to silence disease-causing genes with precision. However, the delivery of siRNA to target cells in-vivo remains a formidable challenge, owing to degradation by nucleases, poor cellular uptake and immunogenicity. This overview examines recent advancements in the design and application of nucleic acid-based integrated macromolecular complexes for the efficient delivery of siRNA. We dissect the innovative delivery vectors developed in recent years, including lipid-based nanoparticles, polymeric carriers, dendrimer complexes and hybrid systems that incorporate stimuli-responsive elements for targeted and controlled release. Advancements in bioconjugation techniques, active targeting strategies and nanotechnology-enabled delivery platforms are evaluated for their contribution to enhancing siRNA delivery. It also addresses the complex interplay between delivery system design and biological barriers, highlighting the dynamic progress and remaining hurdles in translating siRNA therapies from bench to bedside. By offering a comprehensive overview of current strategies and emerging technologies, we underscore the future directions and potential impact of siRNA delivery systems in personalized medicine.

Layer-by-layer nanoparticle encapsulating all-trans retinoic acid and CpG as a mucosal adjuvant targeting colorectal cancer

Colorectal cancer (CRC) ranks among the most prevalent cancers globally, demanding innovative therapeutic strategies. Immunotherapy, a promising avenue, employs cancer vaccines to activate the immune system against tumors. However, conventional approaches fall short of eliciting robust responses within the gastrointestinal (GI) tract, where CRC originates. Harnessing the potential of all-trans retinoic acid (ATRA) and cytosine-phosphorothioate-guanine (CpG), we developed layered nanoparticles using a layer-by-layer assembly method to co-deliver these agents. ATRA, crucial for gut immunity, was efficiently encapsulated alongside CpG within these nanoparticles. Administering these ATRA@CpG-NPs, combined with ovalbumin peptide (OVA), effectively inhibited orthotopic CRC growth in mice. Our approach leveraged the inherent benefits of ATRA and CpG, demonstrating superior efficacy in activating dendritic cells, imprinting T cells with gut-homing receptors, and inhibiting tumor growth. This mucosal adjuvant presents a promising strategy for CRC immunotherapy, showcasing the potential for targeting gut-associated immune responses in combating colorectal malignancies.

A new era of targeting cystic fibrosis with non-viral delivery of genomic medicines

Cystic fibrosis (CF) is a complex genetic respiratory disorder that necessitates innovative gene delivery strategies to address the mutations in the gene. This review delves into the promises and challenges of non-viral gene delivery for CF therapy and explores strategies to overcome these hurdles. Several emerging technologies and nucleic acid cargos for CF gene therapy are discussed. Novel formulation approaches including lipid and polymeric nanoparticles promise enhanced delivery through the CF mucus barrier, augmenting the potential of non-viral strategies. Additionally, safety considerations and regulatory perspectives play a crucial role in navigating the path toward clinical translation of gene therapy.

Lipid nanoparticle mediated small interfering RNA delivery as a potential therapy for Alzheimer's disease

Alzheimer's disease (AD) is a neurodegenerative condition that exhibits a gradual decline in cognitive function and is prevalent among a significant number of individuals globally. The use of small interfering RNA (siRNA) molecules in RNA interference (RNAi) presents a promising therapeutic strategy for AD. Lipid nanoparticles (LNPs) have been developed as a delivery vehicle for siRNA, which can selectively suppress target genes, by enhancing cellular uptake and safeguarding siRNA from degradation. Numerous research studies have exhibited the effectiveness of LNP-mediated siRNA delivery in reducing amyloid beta (Aβ) levels and enhancing cognitive function in animal models of AD. The feasibility of employing LNP-mediated siRNA delivery as a therapeutic approach for AD is emphasized by the encouraging outcomes reported in clinical studies for other medical conditions. The use of LNP-mediated siRNA delivery has emerged as a promising strategy to slow down or even reverse the progression of AD by targeting the synthesis of tau phosphorylation and other genes linked to the condition. Improvement of the delivery mechanism and determination of the most suitable siRNA targets are crucial for the efficacious management of AD. This review focuses on the delivery of siRNA through LNPs as a promising therapeutic strategy for AD, based on the available literature.

Impact of allele-selective silencing of von Willebrand factor in mice based on a single nucleotide allelic difference in von Willebrand factor

INTRODUCTION

Von Willebrand factor (VWF) plays a pathophysiological role in hemostatic disorders. Partial inhibition of the VWF gene through small interfering RNA (siRNA)-mediated allele-selective silencing could be a promising therapeutic strategy. For von Willebrand disease, allele-selectively inhibiting dominant-negative VWF-alleles might ameliorate the phenotype. For thrombotic disorders, partial VWF reduction can lower thrombotic risk, while avoiding bleeding. Previously, we demonstrated the feasibility of Vwf-silencing in homozygous C57BL/6J (B6) or 129S1/SvImJ (129S) mice. The present study investigated allele-selective Vwf-silencing in a complex heterozygous setting of crossed B6 and 129S mice and its subsequent hemostatic impact.

MATERIALS AND METHODS

Heterozygous B6.129S mice were treated with siRNAs targeting Vwf expressed from either B6- (siVwf.B6) or 129S-alleles (siVwf.129S). Plasma VWF and lung Vwf mRNA were determined. siVwf.B6-treated B6.129S mice were subjected to ferric chloride-induced mesenteric vessel thrombosis and tail-bleeding.

RESULTS

In B6.129S mice, siVwf.B6 reduced Vwf mRNA of the targeted B6-allele by 72% vs. only 12% of the non-targeted 129S-allele (41% total mRNA reduction), lowering plasma VWF by 46%. Oppositely, siVwf.129S reduced Vwf mRNA by 45%, now selectively inhibiting the 129S-allele over the B6-allele (58% vs. 9%), decreasing plasma VWF by 43%. The allele-selective VWF reduction by siVwf.B6 coincided with decreased thrombus formation in mesenteric arterioles, without prolonging tail-bleeding times.

CONCLUSIONS

This study demonstrates the feasibility of allele-selective Vwf-silencing in a heterozygous setting, achieving a controlled close to 50% reduction of plasma VWF. The observed thromboprotection and absence of prolonged bleeding times underline the potential of allele-selective Vwf-silencing as a therapeutic strategy in hemostatic disorders.

Strategies for non-viral vectors targeting organs beyond the liver

In recent years, nanoparticles have evolved to a clinical modality to deliver diverse nucleic acids. Rising interest in nanomedicines comes from proven safety and efficacy profiles established by continuous efforts to optimize physicochemical properties and endosomal escape. However, despite their transformative impact on the pharmaceutical industry, the clinical use of non-viral nucleic acid delivery is limited to hepatic diseases and vaccines due to liver accumulation. Overcoming liver tropism of nanoparticles is vital to meet clinical needs in other organs. Understanding the anatomical structure and physiological features of various organs would help to identify potential strategies for fine-tuning nanoparticle characteristics. In this Review, we discuss the source of liver tropism of non-viral vectors, present a brief overview of biological structure, processes and barriers in select organs, highlight approaches available to reach non-liver targets, and discuss techniques to accelerate the discovery of non-hepatic therapies.

Kinetically Controlled Polyelectrolyte Complex Assembly of microRNA-Peptide Nanoparticles toward Treating Mesothelioma

Broad size distributions and poor long-term colloidal stability of microRNA-carrying nanoparticles, especially those formed by polyelectrolyte complexation, represent major hurdles in realizing their clinical translation. Herein, peptide design is used alongside optimized flash nanocomplexation (FNC) to produce uniform peptide-based miRNA particles of exceptional stability that display anticancer activity against mesothelioma in vitro and in vivo. Modulating the content and display of lysine-based charge from small intrinsically disordered peptides used to complex miRNA proves essential in achieving stable colloids. FNC facilitates kinetic isolation of the mechanistic steps involved in particle formation to allow the preparation of particles of discrete size in a highly reproducible, scalable, and continuous manner, facilitating pre-clinical studies. To the best of the authors knowledge, this work represents the first example of employing FNC to prepare polyelectrolyte complexes of miRNA and peptide. Encapsulation of these particles into an injectable hydrogel matrix allows for their localized in vivo delivery by syringe. A one-time injection of a gel containing particles composed of miRNA-215-5p and the peptide PKM1 limits tumor progression in a xenograft model of mesothelioma.

All-Trans-Retinoic Acid-Adjuvanted mRNA Vaccine Induces Mucosal Anti-Tumor Immune Responses for Treating Colorectal Cancer

Messenger RNA (mRNA) cancer vaccines are a new class of immunotherapies that can activate the immune system to recognize and destroy cancer cells. However, their effectiveness in treating colorectal cancer located on the mucosal surface of the gut is limited due to the insufficient activation of mucosal immune response and inadequate infiltration of cytotoxic T cells into tumors. To address this issue, a new mRNA cancer vaccine is developed that can stimulate mucosal immune responses in the gut by co-delivering all-trans-retinoic acid (ATRA) and mRNA using lipid nanoparticle (LNP). The incorporation of ATRA has not only improved the mRNA transfection efficiency of LNP but also induced high expression of gut-homing receptors on vaccine-activated T cells. Additionally, the use of LNP improves the aqueous solubility of ATRA, eliminating the need for toxic solvents to administer ATRA. Upon intramuscular injections, ATRA-adjuvanted mRNA-LNP significantly increase the infiltration of antigen-specific, cytotoxic T cells in the lamina propria of the intestine, mesenteric lymph nodes, and orthotopic colorectal tumors, resulting in significantly improved tumor inhibition and prolonged animal survival compared to conventional mRNA-LNP without ATRA. Overall, this study provides a promising approach for improving the therapeutic efficacy of mRNA cancer vaccines against colorectal cancer.

Cationic cholesterol-dependent LNP delivery to lung stem cells, the liver, and heart

Adding a cationic helper lipid to a lipid nanoparticle (LNP) can increase lung delivery and decrease liver delivery. However, it remains unclear whether charge-dependent tropism is universal or, alternatively, whether it depends on the component that is charged. Here, we report evidence that cationic cholesterol-dependent tropism can differ from cationic helper lipid-dependent tropism. By testing how 196 LNPs delivered mRNA to 22 cell types, we found that charged cholesterols led to a different lung:liver delivery ratio than charged helper lipids. We also found that combining cationic cholesterol with a cationic helper lipid led to mRNA delivery in the heart as well as several lung cell types, including stem cell-like populations. These data highlight the utility of exploring charge-dependent LNP tropism.

Current RNA strategies in treating cardiovascular diseases

Cardiovascular disease (CVD) continues to impose a significant global health burden, necessitating the exploration of innovative treatment strategies. Ribonucleic acid (RNA)-based therapeutics have emerged as a promising avenue to address the complex molecular mechanisms underlying CVD pathogenesis. We present a comprehensive review of the current state of RNA therapeutics in the context of CVD, focusing on the diverse modalities that bring about transient or permanent modifications by targeting the different stages of the molecular biology central dogma. Considering the immense potential of RNA therapeutics, we have identified common gene targets that could serve as potential interventions for prevalent Mendelian CVD caused by single gene mutations, as well as acquired CVDs developed over time due to various factors. These gene targets offer opportunities to develop RNA-based treatments tailored to specific genetic and molecular pathways, presenting a novel and precise approach to address the complex pathogenesis of both types of cardiovascular conditions. Additionally, we discuss the challenges and opportunities associated with delivery strategies to achieve targeted delivery of RNA therapeutics to the cardiovascular system. This review highlights the immense potential of RNA-based interventions as a novel and precise approach to combat CVD, paving the way for future advancements in cardiovascular therapeutics.

Light-field flow cytometry for high-resolution, volumetric and multiparametric 3D single-cell analysis

Imaging flow cytometry (IFC) combines flow cytometry and fluorescence microscopy to enable high-throughput, multiparametric single-cell analysis with rich spatial details. However, current IFC techniques remain limited in their ability to reveal subcellular information with a high 3D resolution, throughput, sensitivity, and instrumental simplicity. In this study, we introduce a light-field flow cytometer (LFC), an IFC system capable of high-content, single-shot, and multi-color acquisition of up to 5,750 cells per second with a near-diffraction-limited resolution of 400-600 nm in all three dimensions. The LFC system integrates optical, microfluidic, and computational strategies to facilitate the volumetric visualization of various 3D subcellular characteristics through convenient access to commonly used epi-fluorescence platforms. We demonstrate the effectiveness of LFC in assaying, analyzing, and enumerating intricate subcellular morphology, function, and heterogeneity using various phantoms and biological specimens. The advancement offered by the LFC system presents a promising methodological pathway for broad cell biological and translational discoveries, with the potential for widespread adoption in biomedical research.

Precision treatment of viral pneumonia through macrophage-targeted lipid nanoparticle delivery

Macrophages are integral components of the innate immune system, playing a dual role in host defense during infection and pathophysiological states. Macrophages contribute to immune responses and aid in combatting various infections, yet their production of abundant proinflammatory cytokines can lead to uncontrolled inflammation and worsened tissue damage. Therefore, reducing macrophage-derived proinflammatory cytokine release represents a promising approach for treating various acute and chronic inflammatory disorders. However, limited macrophage-specific delivery vehicles have hindered the development of macrophage-targeted therapies. In this study, we screened a pool of 112 lipid nanoparticles (LNPs) to identify an optimal LNP formulation for efficient siRNA delivery. Subsequently, by conjugating the macrophage-specific antibody F4/80 to the LNP surface, we constructed MacLNP, an enhanced LNP formulation designed for targeted macrophage delivery. In both in vitro and in vivo experiments, MacLNP demonstrated a significant enhancement in targeting macrophages. Specifically, delivery of siRNA targeting TAK1, a critical kinase upstream of multiple inflammatory pathways, effectively suppressed the phosphorylation/activation of NF-kB. LNP-mediated inhibition of NF-kB, a key upstream regulator in the classic inflammatory signaling pathway, in the murine macrophage cell line RAW264.7 significantly reduced the release of proinflammatory cytokines after stimulation with the viral RNA mimic Poly(I:C). Finally, intranasal administration of MacLNP-encapsulated TAK1 siRNA markedly ameliorated lung injury induced by influenza infection. In conclusion, our findings validate the potential of targeted macrophage interventions in attenuating inflammatory responses, reinforcing the potential of LNP-mediated macrophage targeting to treat pulmonary inflammatory disorders.

Substituting Poly(ethylene glycol) Lipids with Poly(2-ethyl-2-oxazoline) Lipids Improves Lipid Nanoparticle Repeat Dosing

Poly(ethylene glycol) (PEG)-lipids are used in Food-and-Drug-Administration-approved lipid nanoparticle (LNP)-RNA drugs, which are safe and effective. However, it is reported that PEG-lipids may also contribute to accelerated blood clearance and rare cases of hypersensitivity; this highlights the utility of exploring PEG-lipid alternatives. Here, it is shown that LNPs containing poly(2-ethyl-2-oxazoline) (PEOZ)-lipids can deliver messenger RNA (mRNA) to multiple cell types in mice inside and outside the liver. In addition, it is reported that LNPs formulated with PEOZ-lipids show reduced clearance from the bloodstream and lower levels of antistealth lipid immunoglobulin Ms than LNPs formulated with PEG-lipids. These data justify further exploration of PEOZ-lipids as alternatives to PEG-lipids in LNP-RNA formulations.

Zinc(II)-Quinoline module and ROS cleavable crosslinker functionalized self-fluorescent siRNA vectors for selective gene silencing of cancer cells

A highly efficient siRNA vector (Zn-PQD) capable of selectively silencing genes in cancer cells was obtained by using ROS-cleavable DED to crosslink low molecular weight (LMW) polyethylene imine (PEI) modified by self-fluorescent metal coordinatied multifunctional module Zn-QS. Under the combined action of DED cross-linking and Zn-QS modification, Zn-PQD performs well in the siRNA delivery process in cancer cells, including siRNA condensation, cell uptake, endosome escape, and siRNA release. Zn-PQD exhibited higher transfection efficiency than commercial PEI25k and Lipo2k in multiple cancer cell lines including HepG2, HeLa, 4 T1, H520 and PANC-1, as well as cancer treatment-related stem cell rADSC. Ultimately, Zn-PQD can achieve extremely high and selective gene silencing effects in cancer cells (with a gene silencing rate of 98.3% in HepG2). This work is expected to provide an efficient and safe siRNA carrier for the future tumor siRNA therapy and its study of fluorescence mediated mechanism.

MiR126-targeted-nanoparticles combined with PI3K/AKT inhibitor as a new strategy to overcome melanoma resistance

Metastatic melanoma poses significant challenges as a highly lethal disease. Despite the success of molecular targeting using BRAFV600E inhibitors (BRAFis) and immunotherapy, the emergence of early recurrence remains an issue and there is the need for novel therapeutic approaches. This study aimed at creating a targeted delivery system for the oncosuppressor microRNA 126 (miR126) and testing its effectiveness in combination with a phosphatidylinositol 3-kinase (PI3K)/ protein kinase B (AKT) inhibitor for treating metastatic melanoma resistant to BRAFis. To achieve this, we synthesized chitosan nanoparticles containing a chemically modified miR126 sequence. These nanoparticles were further functionalized with an antibody specific to the chondroitin sulfate proteoglycan 4 (CSPG4) melanoma marker. After evaluation in vitro, the efficacy of this treatment was evaluated through an in vivo experiment using mice bearing resistant human melanoma. The co-administration of miR126 and the PI3K/AKT inhibitor in these experiments significantly reduced tumor growth and inhibited the formation of liver and lung metastases. These results provide evidence for a strategy to target an oncosuppressive nucleic acid sequence to tumor cells while simultaneously protecting it from plasma degradation. The system described in this study exhibits encouraging potential for the effective treatment of therapy-resistant metastatic melanoma while also presenting a prospective approach for other forms of cancer.

Building a Better Silver Bullet: Current Status and Perspectives of Non-Viral Vectors for mRNA Vaccines

In recent years, messenger RNA (mRNA) vaccines have exhibited great potential to replace conventional vaccines owing to their low risk of insertional mutagenesis, safety and efficacy, rapid and scalable production, and low-cost manufacturing. With the great achievements of chemical modification and sequence optimization methods of mRNA, the key to the success of mRNA vaccines is strictly dependent on safe and efficient gene vectors. Among various delivery platforms, non-viral mRNA vectors could represent perfect choices for future clinical translation regarding their safety, sufficient packaging capability, low immunogenicity, and versatility. In this review, the recent progress in the development of non-viral mRNA vectors is focused on. Various organic vectors including lipid nanoparticles (LNPs), polymers, peptides, and exosomes for efficient mRNA delivery are presented and summarized. Furthermore, the latest advances in clinical trials of mRNA vaccines are described. Finally, the current challenges and future possibilities for the clinical translation of these promising mRNA vectors are also discussed.

Unlocking Delivery Strategies for mRNA Therapeutics

mRNA emerged as an attractive therapy modality with the development of mRNA structure engineering techniques and delivery platforms. mRNA therapeutics, applied for vaccine therapy, protein replacement therapy, and chimeric antigen receptor (CAR) T cell-based therapy, has shown huge potential in treating a wide range of diseases, such as cancer and rare genetic diseases, with successful and exciting preclinical and clinical progress. In mRNA therapeutics, a potent delivery system is key to the success of its application for disease treatment. Herein, different types of mRNA delivery strategies, including nanoparticles produced from lipid or polymer materials, virus-based platforms, and exosome-based platforms, are mainly focused.

Fluorescence Super-Resolution Imaging Chip for Gene Silencing Exosomes

Tumor cell-derived extracellular vesicles and their cargo of bioactive substances have gradually been recognized as novel biomarkers for cancer diagnosis. Meanwhile, the PD-L1 (Programmed Death-Ligand 1) protein, as an immune checkpoint molecule, is highly expressed on certain tumor cells and holds significant potential in immune therapy. In comparison to PD-L1 monoclonal antibodies, the inhibitory effect of PD-L1 siRNA (small interfering RNA) is more advantageous. In this article, we introduced a microfluidic chip integrating cell cultivation and exosome detection modules, which were intended for the investigation of the gene silencing effect of PD-L1 siRNA. Basically, cells were first cultured with PD-L1 siRNA in the chip. Then, the secreted exosomes were detected via super-resolution imaging, to validate the inhibitory effect of siRNA on PD-L1 expression. To be specific, a "sandwich" immunological structure was employed to detect exosomes secreted from HeLa cells. Immunofluorescence staining and DNA-PAINT (DNA Point Accumulation for Imaging in Nanoscale Topography) techniques were utilized to quantitatively analyze the PD-L1 proteins on HeLa exosomes, which enabled precise structural and content analysis of the exosomes. Compared with other existing PD-L1 detection methods, the advantages of our work include, first, the integration of microfluidic chips greatly simplifying the cell culture, gene silencing, and PD-L1 detection procedures. Second, the utilization of DNA-PAINT can provide an ultra-high spatial resolution, which is beneficial for exosomes due to their small sizes. Third, qPAINT could allow quantitative detection of PD-L1 with better precision. Hence, the combination of the microfluidic chip with DNA-PAINT could provide a more powerful integrated platform for the study of PD-L1-related tumor immunotherapy.

Bioinspired Spatiotemporal Management toward RNA Therapies

Ribonucleic acid (RNA)-based therapies have become an attractive topic in disease intervention, especially with some that have been approved by the FDA such as the mRNA COVID-19 vaccine (Comirnaty, Pfizer-BioNTech, and Spikevax, Moderna) and Patisiran (siRNA-based drug for liver delivery). However, extensive applications are still facing challenges in delivering highly negatively charged RNA to the targeted site. Therapeutic delivery strategies including RNA modifications, RNA conjugates, and RNA polyplexes and delivery platforms such as viral vectors, nanoparticle-based delivery platforms, and hydrogel-based delivery platforms as potential nucleic acid-releasing depots have been developed to enhance their cellular uptake and protect nucleic acid from being degraded by immune systems. Here, we review the growing number of viral vectors, nanoparticles, and hydrogel-based RNA delivery systems; describe RNA loading/release mechanism induced by environmental stimulations including light, heat, pH, or enzyme; discuss their physical or chemical interactions; and summarize the RNA therapeutics release period (temporal) and their target cells/organs (spatial). Finally, we describe current concerns, highlight current challenges and future perspectives of RNA-based delivery systems, and provide some possible research areas that provide opportunities for clinical translation of RNA delivery carriers.

Delivery of nucleic acids using nanomaterials

The increasing number of approved nucleic acid therapeutics demonstrates the potential for the prevention and treatment of a broad spectrum of diseases. This trend underscores the significant impact and promise of nucleic acid-based treatments in the field of medicine. Nevertheless, employing nucleic acids as therapeutics is challenging due to their susceptibility to degradation by nucleases and their unfavorable physicochemical characteristics that hinder delivery into cells. Appropriate vectors play a pivotal role in improving nucleic acid stability and delivering nucleic acids into specific cells. The maturation of delivery systems has led to breakthroughs in the development of therapeutics based on nucleic acids such as DNA, siRNA, and mRNA. Non-viral vectors have gained prominence among the myriad of nanomaterials due to low immunogenicity, ease of manufacturing, and simplicity of cost-effective, large-scale production. Here, we provide an overview of the recent advancements in nanomaterials for nucleic acid delivery. Specifically, we give a detailed introduction to the characteristics of polymers, lipids, and polymer-lipid hybrids, and provide comprehensive descriptions of their applications in nucleic acid delivery. Also, biological barriers, administration routes, and strategies for organ-selective delivery of nucleic acids are discussed. In summary, this review offers insights into the rational design of next-generation delivery vectors for nucleic acid delivery.

Cationic LNP-formulated mRNA expressing Tie2-agonist in the lung endothelium prevents pulmonary vascular leakage

Dysfunction of endothelial cells (ECs) lining the inner surface of blood vessels are causative for a number of diseases. Hence, the ability to therapeutically modulate gene expression within ECs is of high therapeutic value in treating diseases such as those associated with lung edema. mRNAs formulated with lipid nanoparticles (LNPs) have emerged as a new drug modality to induce transient protein expression for modulating disease-relevant signal transduction pathways. In the study presented here, we tested the effect of a novel synthetic, nucleoside-modified mRNA encoding COMP-Ang1 (mRNA-76) formulated into a cationic LNP on attenuating inflammation-induced vascular leakage. After intravenous injection, the respective mRNA was found to be delivered almost exclusively to the ECs of the lung, while sparing other vascular beds and bypassing the liver. The mode of action of mRNA-76, such as its activation of the Tie2 signal transduction pathway, was tested by pharmacological studies in vitro and in vivo in respective mouse models. mRNA-76 was found to prevent lung vascular leakage/lung edema as well as neutrophil infiltration in a lipopolysaccharide-challenging model.

Lipid Nanoparticle (LNP) Enables mRNA Delivery for Cancer Therapy

Messenger RNA (mRNA) has received great attention in the prevention and treatment of various diseases due to the success of coronavirus disease 2019 (COVID-19) mRNA vaccines (Comirnaty and Spikevax). To meet the therapeutic purpose, it is required that mRNA must enter the target cells and express sufficient proteins. Therefore, the development of effective delivery systems is necessary and crucial. Lipid nanoparticle (LNP) represents a remarkable vehicle that has indeed accelerated mRNA applications in humans, as several mRNA-based therapies have already been approved or are in clinical trials. In this review, the focus is on mRNA-LNP-mediated anticancer therapy. It summarizes the main development strategies of mRNA-LNP formulations, discusses representative therapeutic approaches in cancer, and points out current challenges and possible future directions of this research field. It is hoped that these delivered messages can help further improve the application of mRNA-LNP technology in cancer therapy.

Unlocking the potential of RNA-based therapeutics in the lung: current status and future directions

Awareness of RNA-based therapies has increased after the widespread adoption of mRNA vaccines against SARS-CoV-2 during the COVID-19 pandemic. These mRNA vaccines had a significant impact on reducing lung disease and mortality. They highlighted the potential for rapid development of RNA-based therapies and advances in nanoparticle delivery systems. Along with the rapid advancement in RNA biology, including the description of noncoding RNAs as major products of the genome, this success presents an opportunity to highlight the potential of RNA as a therapeutic modality. Here, we review the expanding compendium of RNA-based therapies, their mechanisms of action and examples of application in the lung. The airways provide a convenient conduit for drug delivery to the lungs with decreased systemic exposure. This review will also describe other delivery methods, including local delivery to the pleura and delivery vehicles that can target the lung after systemic administration, each providing access options that are advantageous for a specific application. We present clinical trials of RNA-based therapy in lung disease and potential areas for future directions. This review aims to provide an overview that will bring together researchers and clinicians to advance this burgeoning field.

M2pep-Modified Cyclodextrin-siRNA Nanoparticles Modulate the Immunosuppressive Tumor Microenvironment for Prostate Cancer Therapy

Prostate cancer (PCa) is the most prevalent cause of cancer deaths in men. Conventional strategies, such as surgery, radiation, or chemotherapy, face challenges including poor prognosis and resistance. Therefore, the development of new improved strategies is vital to enhance patient outcomes. Recently, immunotherapy has shown potential in the treatment of a range of cancers, including PCa. Tumor-associated macrophages (TAMs) play an important role in the tumor microenvironment (TME) and reprogramming of TAMs is associated with remodeling the TME. The colony-stimulating factor-1/colony stimulating factor-1 receptor (CSF-1/CSF-1R) signaling pathway is closely related to the polarization of TAMs. The downregulation of CSF-1R, using small interfering RNA (siRNA), has been shown to achieve the reprogramming of TAMs, from the immunosuppressive M2 phenotype to the immunostimulatory M1 one. To maximize specific cellular delivery an M2 macrophage-targeting peptide, M2pep, was formulated with an amphiphilic cationic β-Cyclodextrin (CD) incorporating CSF-1R siRNA. The resulting nanoparticles (NPs) increased M2 macrophage targeting both in vitro and in vivo, promoting the release of M1 factors and simultaneously downregulating the levels of M2 factors through TAM reprogramming. The subsequent remodeling of the TME resulted in a reduction in tumor growth in a subcutaneous PCa mouse model mainly mediated through the recruitment of cytotoxic T cells. In summary, this M2pep-targeted CD-based delivery system demonstrated significant antitumor efficacy, thus presenting an alternative immunotherapeutic strategy for PCa treatment.

Drug delivery systems for CRISPR-based genome editors

CRISPR-based drugs can theoretically manipulate any genetic target. In practice, however, these drugs must enter the desired cell without eliciting an unwanted immune response, so a delivery system is often required. Here, we review drug delivery systems for CRISPR-based genome editors, focusing on adeno-associated viruses and lipid nanoparticles. After describing how these systems are engineered and their subsequent characterization in preclinical animal models, we highlight data from recent clinical trials. Preclinical targeting mediated by polymers, proteins, including virus-like particles, and other vehicles that may deliver CRISPR systems in the future is also discussed.

'Passive' nanoparticles for organ-selective systemic delivery: design, mechanism and perspective

Nanotechnology has shown tremendous success in the drug delivery field for more effective and safer therapy, and has recently enabled the clinical approval of RNA medicine, a new class of therapeutics. Various nanoparticle strategies have been developed to improve the systemic delivery of therapeutics, among which surface modification of targeting ligands on nanoparticles has been widely explored for 'active' delivery to a specific organ or diseased tissue. Meanwhile, compelling evidence has recently been reported that organ-selective targeting may also be achievable by systemic administration of nanoparticles without surface ligand modification. In this Review, we highlight this unique set of 'passive' nanoparticles and their compositions and mechanisms for organ-selective delivery. In particular, the lipid-based, polymer-based, and biomimetic nanoparticles with tropism to different specific organs after intravenous administration are summarized. The underlying mechanisms (e.g., protein corona and size effect) of these nanosystems for organ selectivity are also extensively discussed. We further provide perspectives on the opportunities and challenges in this exciting area of organ-selective systemic nanoparticle delivery.

Small interfering RNA-mediated allele-selective silencing of von Willebrand factor in vitro and in vivo

An imbalance in von Willebrand factor (VWF) may either lead to bleeding (von Willebrand disease, VWD) or thrombosis. Both disorders have shortcomings in the currently available treatments. VWF itself could be a potential therapeutic target because of its role in both bleeding and thrombosis. Inhibiting VWF gene expression through allele-selective silencing of VWF with small interfering RNAs (siRNAs) could be a personalized approach to specifically inhibit mutant VWF in VWD or to normalize increased VWF levels in thrombotic disorders without complete VWF knockdown. Therefore, we investigated a method to allele-selectively silence the VWF gene in mice as a therapeutic strategy. Fourteen candidate siRNAs targeting murine Vwf of either the C57BL/6J (B6) or the 129S1/SvImJ (129S) strain were tested in vitro in cells expressing B6- and 129S-Vwf for inhibitory effect and allele-selective potential. Together with a nonselective siVwf, 2 lead candidate siRNAs, siVwf.B6 and siVwf.129S, were further tested in vivo in B6 and 129S mice. Efficient endothelial siRNA delivery was achieved by siRNA encapsulation into 7C1 oligomeric lipid nanoparticles. Treatment with the nonselective siVwf resulted in dose-dependent inhibition of up to 80% of both lung messenger RNA and plasma VWF protein in both mouse strains. In contrast, the allele-selective siVwf.B6 and siVwf.129S were shown to be effective in and selective solely for their corresponding mouse strain. To conclude, we showed efficient endothelial delivery of siRNAs that are highly effective in allele-selective inhibition of Vwf in mice, which constitutes an in vivo proof of principle of allele-selective VWF silencing as a therapeutic approach.

High-efficiency green management of potato late blight by a self-assembled multicomponent nano-bioprotectant

Potato late blight caused by Phytophthora infestans is a devastating disease worldwide. Unlike other plant pathogens, double-stranded RNA (dsRNA) is poorly taken up by P. infestans, which is a key obstacle in using dsRNA for disease control. Here, a self-assembled multicomponent nano-bioprotectant for potato late blight management is designed based on dsRNA and a plant elicitor. Nanotechnology overcomes the dsRNA delivery bottleneck for P. infestans and extends the RNAi protective window. The protective effect of nano-enabled dsRNA against infection arises from a synergistic mechanism that bolsters the stability of dsRNA and optimizes its effective intracellular delivery. Additionally, the nano-enabled elicitor enhances endocytosis and amplifies the systemic defense response of the plants. Co-delivery of dsRNA and an elicitor provides a protective effect via the two aspects of pathogen inhibition and elevated plant defense mechanisms. The multicomponent nano-bioprotectant exhibits superior control efficacy compared to a commercial synthetic pesticide in field conditions. This work proposes an eco-friendly strategy to manage devastating plant diseases and pests.

Recent advances and prospects for lipid-based nanoparticles as drug carriers in the treatment of human retinal diseases

The delivery of cures for retinal diseases remains problematic. There are four main challenges: passing through multiple barriers of the eye, the delivery to particular retinal cell types, the capability to carry different forms of therapeutic cargo and long-term therapeutic efficacy. Lipid-based nanoparticles (LBNPs) are potent to overcome these challenges due to their unique merits: amphiphilic nanoarchitectures to pass biological barriers, vary modifications with specific affinity to target cell types, flexible capacity for large and mixed types of cargos and slow-release formulations for long-term treatment. We have reviewed the latest research on the applications of LBNPs for treating retinal diseases and categorized them by different payloads. Furthermore, we identified technical barriers and discussed possible future development for LBNPs to expand the therapeutic potential in treating retinal diseases.

siRNA Lipid-Polymer Nanoparticles Targeting E-Selectin and Cyclophilin A in Bone Marrow for Combination Multiple Myeloma Therapy

Introduction

Multiple myeloma (MM) is a hematological blood cancer of the bone marrow that remains largely incurable, in part due to its physical interactions with the bone marrow microenvironment. Such interactions enhance the homing, proliferation, and drug resistance of MM cells. Specifically, adhesion receptors and homing factors, E-selectin (ES) and cyclophilin A (CyPA), respectively, expressed by bone marrow endothelial cells enhance MM colonization and dissemination. Thus, silencing of ES and CyPA presents a potential therapeutic strategy to evade MM spreading. However, small molecule inhibition of ES and CyPA expressed by bone marrow endothelial cells remains challenging, and blocking antibodies induce further MM propagation. Therefore, ES and CyPA are promising candidates for inhibition via RNA interference (RNAi).

Methods

Here, we utilized a previously developed lipid-polymer nanoparticle for RNAi therapy, that delivers siRNA to the bone marrow perivascular niche. We utilized our platform to co-deliver ES and CyPA siRNAs to prevent MM dissemination in vivo.

Results

Lipid-polymer nanoparticles effectively downregulated ES expression in vitro, which decreased MM cell adhesion and migration through endothelial monolayers. Additionally, in vivo delivery of lipid-polymer nanoparticles co-encapsulating ES and CyPA siRNA extended survival in a xenograft mouse model of MM, either alone or in combination with the proteasome inhibitor bortezomib.

Conclusions

Our combination siRNA lipid-polymer nanoparticle therapy presents a vascular microenvironment-targeting strategy as a potential paradigm shift for MM therapies, which could be extended to other cancers that colonize the bone marrow.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12195-023-00774-y.

Intelligent Biomaterialomics: Molecular Design, Manufacturing, and Biomedical Applications

Materialomics integrates experiment, theory, and computation in a high-throughput manner, and has changed the paradigm for the research and development of new functional materials. Recently, with the rapid development of high-throughput characterization and machine-learning technologies, the establishment of biomaterialomics that tackles complex physiological behaviors has become accessible. Breakthroughs in the clinical translation of nanoparticle-based therapeutics and vaccines have been observed. Herein, recent advances in biomaterials, including polymers, lipid-like materials, and peptides/proteins, discovered through high-throughput screening or machine learning-assisted methods, are summarized. The molecular design of structure-diversified libraries; high-throughput characterization, screening, and preparation; and, their applications in drug delivery and clinical translation are discussed in detail. Furthermore, the prospects and main challenges in future biomaterialomics and high-throughput screening development are highlighted.

In utero delivery of miRNA induces epigenetic alterations and corrects pulmonary pathology in congenital diaphragmatic hernia

Structural fetal diseases, such as congenital diaphragmatic hernia (CDH) can be diagnosed prenatally. Neonates with CDH are healthy in utero as gas exchange is managed by the placenta, but impaired lung function results in critical illness from the time a baby takes its first breath. MicroRNA (miR) 200b and its downstream targets in the TGF-β pathway are critically involved in lung branching morphogenesis. Here, we characterize the expression of miR200b and the TGF-β pathway at different gestational times using a rat model of CDH. Fetal rats with CDH are deficient in miR200b at gestational day 18. We demonstrate that novel polymeric nanoparticles loaded with miR200b, delivered in utero via vitelline vein injection to fetal rats with CDH results in changes in the TGF-β pathway as measured by qRT-PCR; these epigenetic changes improve lung size and lung morphology, and lead to favorable pulmonary vascular remodeling on histology. This is the first demonstration of in utero epigenetic therapy to improve lung growth and development in a pre-clinical model. With refinement, this technique could be applied to fetal cases of CDH or other forms of impaired lung development in a minimally invasive fashion.

TGFβ signaling pathways in human health and disease

Transforming growth factor beta (TGFβ) is named for the function it was originally discovered to perform-transformation of normal cells into aggressively growing malignant cells. It became apparent after more than 30 years of research, however, that TGFβ is a multifaceted molecule with a myriad of different activities. TGFβs are widely expressed with almost every cell in the human body producing one or another TGFβ family member and expressing its receptors. Importantly, specific effects of this growth factor family differ in different cell types and under different physiologic and pathologic conditions. One of the more important and critical TGFβ activities is the regulation of cell fate, especially in the vasculature, that will be the focus of this review.

A fluorinated ionizable lipid improves the mRNA delivery efficiency of lipid nanoparticles

The efficacy of messenger RNA (mRNA)-based vaccines or therapies relies on delivery vehicles that can transport them into the cytosol of cells. Lipid nanoparticles (LNPs) are the most clinically advanced carrier for mRNA. The chemical structure of an ionizable lipid is critical for the delivery efficiency of the LNPs. Herein, we synthesize a new ionizable lipid containing fluorinated alkyl chains (F-L319) and evaluate its mRNA delivery efficiency compared to its hydrocarbon counterpart (L319). While LNPs formulated with F-L319 alone showed decreased mRNA encapsulation and delivery efficiencies in comparison to the L319-LNP, we found that combining the appropriate ratios of F-L319 and L319 as hybrid ionizable lipids in LNPs (hybrid-LNPs) greatly enhanced mRNA delivery efficiency both in vitro and in vivo. Upon intravenous injection, the hybrid-LNP showed targeted mRNA expression in the spleen. Mechanistic studies indicate that the enhanced mRNA delivery of the hybrid-LNP is attributed to both improved mRNA encapsulation and cellular uptake. Collectively, fluorination of ionizable lipids represents a promising strategy to improve the delivery efficiency of LNPs.

BMPR1A promotes ID2-ZEB1 interaction to suppress excessive endothelial to mesenchymal transition

AIMS

Components of bone morphogenetic protein (BMP) signalling have been implicated in both pathogenesis of pulmonary arterial hypertension (PAH) and endothelial-mesenchymal transition (EndoMT). In particular, the importance of BMP type 2 receptor in these processes has been extensively analysed. However, the contribution of BMP type 1 receptors (BMPR1s) to the onset of PAH and EndoMT remains poorly understood. BMPR1A, one of BMPR1s, was recently implicated in the pathogenesis of PAH, and was found to be down-regulated in the lungs of PAH patients, neither the downstream mechanism nor its contribution to EndoMT has been described. Therefore, we aim to delineate the role of endothelial BMPR1A in modulating EndoMT and pathogenesis of PAH.

METHODS AND RESULTS

We find that BMPR1A knockdown in endothelial cells (ECs) induces hallmarks of EndoMT, and deletion of endothelial Bmpr1a in adult mice (Bmpr1aiECKO) leads to development of PAH-like symptoms due to excessive EndoMT. By lineage tracing, we show that endothelial-derived smooth muscle cells are increased in endothelial Bmpr1a-deleted mice. Mechanistically, we identify ZEB1 as a primary target for BMPR1A in this setting; upon BMPR1A activation, ID2 physically interacts and sequesters ZEB1 to attenuate transcription of Tgfbr2, which in turn lowers the responses of ECs towards transforming growth factor beta (TGFβ) stimulation and prevents excessive EndoMT. In Bmpr1aiECKO mice, administering endothelial targeting lipid nanoparticles containing siRNA against Tgfbr2 effectively ameliorate PAH, reiterating the importance of BMPR1A-ID2/ZEB1-TGFBR2 axis in modulating progression of EndoMT and pathogenesis of PAH.

CONCLUSIONS

We demonstrate that BMPR1A is key to maintain endothelial identity and to prevent excessive EndoMT. We identify BMPR1A-induced interaction between ID2 and ZEB1 is the key regulatory step for onset of EndoMT and pathogenesis of PAH. Our findings indicate that BMPR1A-ID2/ZEB1-TGFBR2 signalling axis could serve as a potential novel therapeutic target for PAH and other EndoMT-related vascular disorders.

High-throughput screens identify a lipid nanoparticle that preferentially delivers mRNA to human tumors in vivo

Lipid nanoparticles (LNPs) are a clinically relevant way to deliver therapeutic mRNA to hepatocytes in patients. However, LNP-mRNA delivery to end-stage solid tumors such as head and neck squamous cell carcinoma (HNSCC) remains more challenging. While scientists have used in vitro assays to evaluate potential nanoparticles for HNSCC delivery, high-throughput delivery assays performed directly in vivo have not been reported. Here we use a high-throughput LNP assay to evaluate how 94 chemically distinct nanoparticles delivered nucleic acids to HNSCC solid tumors in vivo. DNA barcodes were used to identify LNPHNSCC, a novel LNP for systemic delivery to HNSCC solid tumors. Importantly, LNPHNSCC retains tropism to HNSCC solid tumors while minimizing off-target delivery to the liver.

Omics are Getting Us Closer to Understanding IgA Nephropathy

During the last decade, thanks to omics technologies, new light has been shed on the pathogenesis of many diseases. Genomics, epigenomics, transcriptomics, and proteomics have helped to provide a better understanding of the origin and heterogeneity of several diseases. However, the risk factors for most autoimmune diseases remain unknown. The successes and pitfalls of omics have also been observed in nephrology, including immunoglobulin A nephropathy (IgAN), the most common form of glomerulonephritis and a principal cause of end-stage renal disease worldwide. Unfortunately, the immense progress in basic research has not yet been followed by the satisfactory development of a targeted treatment. Although, most omics studies describe changes in the immune system, there is still insufficient data to apply their results in the constantly evolving multi-hit pathogenesis model and thus do to provide a complete picture of the disease. Here, we describe recent findings regarding the pathophysiology of IgAN and link omics studies with immune system dysregulation. This review provides insights into specific IgAN markers, which may lead to the identification of potential targets for personalised treatment in the future.

Nanomedicines: intervention in inflammatory pathways of cancer

Inflammation is a complex defense process that maintains tissue homeostasis. However, this complex cascade, if lasts long, may contribute to pathogenesis of several diseases. Chronic inflammation has been exhaustively studied in the last few decades, for its contribution in development and progression of cancer. The intrinsic limitations of conventional anti-inflammatory and anti-cancer therapies triggered the development of nanomedicines for more effective and safer therapies. Targeting inflammation and tumor cells by nanoparticles, encapsulated with active therapeutic agents, offers a promising outcome with patient survival. Considerable technological success has been achieved in this field through exploitation of tumor microenvironment, and recognition of molecules overexpressed on endothelial cells or macrophages, through enhanced vascular permeability, or by rendering biomimetic approach to nanoparticles. This review focusses on the inflammatory pathways in progression of a tumor, and advancement in nanotechnologies targeting these pathways. We also aim to identify the gaps that hinder the successful clinical translation of nanotherapeutics with further clinical studies that will allow oncologist to precisely identify the patients who may be benefited from nanotherapy at time when promotion or progression of tumor initiates. It is postulated that the nanomedicines, in near future, will shift the paradigm of cancer treatment and improve patient survival.

Key Design Features of Lipid Nanoparticles and Electrostatic Charge-Based Lipid Nanoparticle Targeting

Lipid nanoparticles (LNP) have gained much attention after the approval of mRNA COVID-19 vaccines. The considerable number of currently ongoing clinical studies are testament to this fact. These efforts towards the development of LNPs warrant an insight into the fundamental developmental aspects of such systems. In this review, we discuss the key design aspects that confer efficacy to a LNP delivery system, i.e., potency, biodegradability, and immunogenicity. We also cover the underlying considerations regarding the route of administration and targeting of LNPs to hepatic and non-hepatic targets. Furthermore, since LNP efficacy is also a function of drug/nucleic acid release within endosomes, we take a holistic view of charged-based targeting approaches of LNPs not only in the context of endosomal escape but also in relation to other comparable target cell internalization strategies. Electrostatic charge-based interactions have been used in the past as a potential strategy to enhance the drug release from pH-sensitive liposomes. In this review, we cover such strategies around endosomal escape and cell internalization in low pH tumor micro-environments.

Nanoparticle stereochemistry-dependent endocytic processing improves in vivo mRNA delivery

Stereochemistry can alter small-molecule pharmacokinetics, safety and efficacy. However, it is unclear whether the stereochemistry of a single compound within a multicomponent colloid such as a lipid nanoparticle (LNP) can influence its activity in vivo. Here we report that LNPs containing stereopure 20α-hydroxycholesterol (20α) delivered mRNA to liver cells up to 3-fold more potently than LNPs containing a mixture of both 20α- and 20β-hydroxycholesterols (20mix). This effect was not driven by LNP physiochemical traits. Instead, in vivo single-cell RNA sequencing and imaging revealed that 20mix LNPs were sorted into phagocytic pathways more than 20α LNPs, resulting in key differences between LNP biodistribution and subsequent LNP functional delivery. These data are consistent with the fact that nanoparticle biodistribution is necessary, but not sufficient, for mRNA delivery, and that stereochemistry-dependent interactions between LNPs and target cells can improve mRNA delivery.

Nanotechnology-enabled gene delivery for cancer and other genetic diseases

INTRODUCTION

Despite gene therapy is ideal for genetic abnormality-related diseases, the easy degradation, poor targeting, and inefficiency in entering targeted cells are plaguing the effective delivery of gene therapy. Viral and non-viral vectors have been used for delivering gene therapeutics in vivo by safeguarding nucleic acid agents to target cells and to reach the specific intracellular location. A variety of nanotechnology-enabled safe and efficient systems have been successfully developed to improve the targeting ability for effective therapeutic delivery of genetic drugs.

AREAS COVERED

In this review, we outline the multiple biological barriers associated with gene delivery process, and highlight recent advances to gene therapy strategy in vivo, including gene correction, gene silencing, gene activation and genome editing. We point out current developments and challenges exist of non-viral and viral vector systems in association with chemical and physical gene delivery technologies and their potential for the future.

EXPERT OPINION

This review focuses on the opportunities and challenges to various gene therapy strategy, with specific emphasis on overcoming the challenges through the development of biocompatibility and smart gene vectors for potential clinical application.

Deciphering endothelial heterogeneity in health and disease at single-cell resolution: progress and perspectives

Endothelial cells (ECs) constitute the inner lining of vascular beds in mammals and are crucial for homeostatic regulation of blood vessel physiology, but also play a key role in pathogenesis of many diseases, thereby representing realistic therapeutic targets. However, it has become evident that ECs are heterogeneous, encompassing several subtypes with distinct functions, which makes EC targeting and modulation in diseases challenging. The rise of the new single-cell era has led to an emergence of studies aimed at interrogating transcriptome diversity along the vascular tree, and has revolutionized our understanding of EC heterogeneity from both a physiological and pathophysiological context. Here, we discuss recent landmark studies aimed at teasing apart the heterogeneous nature of ECs. We cover driving (epi)genetic, transcriptomic, and metabolic forces underlying EC heterogeneity in health and disease, as well as current strategies used to combat disease-enriched EC phenotypes, and propose strategies to transcend largely descriptive heterogeneity towards prioritization and functional validation of therapeutically targetable drivers of EC diversity. Lastly, we provide an overview of the most recent advances and hurdles in single EC OMICs.

Multifunctional gold nanorods in low-temperature photothermal interactions for combined tumor starvation and RNA interference therapy

Collateral damage to healthy tissue, uneven heat distribution, inflammatory diseases, and tumor metastasis induction hinder the translation of high-temperature photothermal therapy (PTT) from bench to practical clinical applications. In this report, a multifunctional gold nanorod (GNR)-based nanosystem was designed by attaching siRNA against B7-H3 (B7-H3si), glucose oxidase (GOx), and hyaluronic acid (HA) for efficient low-temperature PTT. Herein, GOx can not only exhaust glucose to induce starvation therapy but also reduce the heat shock protein (HSP), realizing the ablation of tumors without damage to healthy tissues. Evidence shows that B7-H3, a type I transmembrane glycoprotein molecule, plays essential roles in growth, metastasis, and drug resistance. By initiating the downregulation of B7-H3 by siRNA, siRNA-GOx/GNR@HA NPs may promote the effectiveness of treatment. By targeting cluster of differentiation 44 (CD44) and depleting B7-H3 and HSPs sequentially, siRNA-GOx/GNR@HA NPs showed 12.9-fold higher lung distribution than siRNA-GOx/GNR NPs. Furthermore, 50% of A549-bearing mice in the siRNA-GOx/GNR NPs group survived over 50 days. Overall, this low-temperature phototherapeutic nanosystem provides an appropriate strategy for eliminating cancer with high treatment effectiveness and minimal systemic toxicity. STATEMENT OF SIGNIFICANCE: To realize efficient tumor ablation under mild low-temperature (42-45 ℃) and RNA interference simultaneously, here we developed a multifunctional gold nanorod (GNR)-based nanosystem (siRNA-GOx/GNR@HA NPs). This nanoplatform can significantly inhibit tumor cell proliferation and induce cell apoptosis by downregulation of HSP90α, HSP70, B7-H3, p-AKT, and p-ERK and upregulation of cleaved caspase-9 at mild low-temperature due to its superior tumor homing ability and the combined effect of photothermal effect, glucose deprivation-initiated tumor starvation, and B7-H3 gene silence effect. It is believed that this multifunctional low-temperature photothermal nanosystem with efficient and specific anticancer properties, shows a potential application in clinical tumor treatment.

Targeted nanomedicine: Lessons learned and future directions

Designing a therapeutic modality that will reach a certain organ, tissue, or cell type is crucial for both the therapeutic efficiency and to limit off-target adverse effects. Nanoparticles carrying various drugs, such as nucleic acids, small molecules and proteins, are promoting modalities to this end. Beyond the need to identify a target for a specific indication, an adequate design has to address the multiple biological barriers, such as systemic barriers, dilution and unspecific distribution, tissue penetration and intracellular trafficking. The field of targeted delivery has developed rapidly in recent years, with tremendous progress made in understating the biological barriers, and new technologies to functionalize nanoparticles with targeting moieties for an accurate, specific and highly selective delivery. Implementing new approaches like multi-functionalized nanocarriers and machine learning models will advance the field for designing safe, cell -specific nanoparticle delivery systems. Here, we will critically review the current progress in the field and suggest novel strategies to improve cell specific delivery of therapeutic payloads.

Ionizable drug delivery systems for efficient and selective gene therapy

Gene therapy has shown great potential to treat various diseases by repairing the abnormal gene function. However, a great challenge in bringing the nucleic acid formulations to the market is the safe and effective delivery to the specific tissues and cells. To be excited, the development of ionizable drug delivery systems (IDDSs) has promoted a great breakthrough as evidenced by the approval of the BNT162b2 vaccine for prevention of coronavirus disease 2019 (COVID-19) in 2021. Compared with conventional cationic gene vectors, IDDSs can decrease the toxicity of carriers to cell membranes, and increase cellular uptake and endosomal escape of nucleic acids by their unique pH-responsive structures. Despite the progress, there remain necessary requirements for designing more efficient IDDSs for precise gene therapy. Herein, we systematically classify the IDDSs and summarize the characteristics and advantages of IDDSs in order to explore the underlying design mechanisms. The delivery mechanisms and therapeutic applications of IDDSs are comprehensively reviewed for the delivery of pDNA and four kinds of RNA. In particular, organ selecting considerations and high-throughput screening are highlighted to explore efficiently multifunctional ionizable nanomaterials with superior gene delivery capacity. We anticipate providing references for researchers to rationally design more efficient and accurate targeted gene delivery systems in the future, and indicate ideas for developing next generation gene vectors.

In utero delivery of mRNA to the heart, diaphragm and muscle with lipid nanoparticles

Nanoparticle-based drug delivery systems have the potential to revolutionize medicine, but their low vascular permeability and rapid clearance by phagocytic cells have limited their medical impact. Nanoparticles delivered at the in utero stage can overcome these key limitations due to the high rate of angiogenesis and cell division in fetal tissue and the under-developed immune system. However, very little is known about nanoparticle drug delivery at the fetal stage of development. In this report, using Ai9 CRE reporter mice, we demonstrate that lipid nanoparticle (LNP) mRNA complexes can deliver mRNA in utero, and can access and transfect major organs, such as the heart, the liver, kidneys, lungs and the gastrointestinal tract with remarkable efficiency and low toxicity. In addition, at 4 weeks after birth, we demonstrate that 50.99 ± 5.05%, 36.62 ± 3.42% and 23.7 ± 3.21% of myofiber in the diaphragm, heart and skeletal muscle, respectively, were transfected. Finally, we show here that Cas9 mRNA and sgRNA complexed to LNPs were able to edit the fetal organs in utero. These experiments demonstrate the possibility of non-viral delivery of mRNA to organs outside of the liver in utero, which provides a promising strategy for treating a wide variety of devastating diseases before birth.

High-Precision Synthesis of RNA-Loaded Lipid Nanoparticles for Biomedical Applications

The recent development of RNA-based therapeutics in delivering nucleic acids for gene editing and regulating protein translation has led to the effective treatment of various diseases including cancer, inflammatory and genetic disorder, as well as infectious diseases. Among these, lipid nanoparticles (LNP) have emerged as a promising platform for RNA delivery and have shed light by resolving the inherent instability issues of naked RNA and thereby enhancing the therapeutic potency. These LNP consisting of ionizable lipid, helper lipid, cholesterol, and poly(ethylene glycol)-anchored lipid can stably enclose RNA and help them release into the cells' cytosol. Herein, the significant progress made in LNP research starting from the LNP constituents, formulation, and their diverse applications is summarized first. Moreover, the microfluidic methodologies which allow precise assembly of these newly developed constituents to achieve LNP with controllable composition and size, high encapsulation efficiency as well as scalable production are highlighted. Furthermore, a short discussion on current challenges as well as an outlook will be given on emerging approaches to resolving these issues.

Engineered ionizable lipid nanoparticles mediated efficient siRNA delivery to macrophages for anti-inflammatory treatment of acute liver injury

Small interfering RNA (siRNA) mediating specific gene silencing provides a promising strategy for anti-inflammatory therapy. However, the development of potent carriers for anti-inflammatory siRNA to macrophages remains challenging. With the aim of realizing potent delivery of siRNA to macrophages, we engineered ionizable lipid nanoparticles (LNPs) with the key component of synthetic lipid-like materials. By varying the amine molecules in the structure of synthetic lipid-like materials, a potent LNP (1O₁₄-LNP) was identified, which exhibited efficient transfection of macrophages by facilitating efficient internalization and endosomal escape. The 1O₁₄-LNP successfully delivered anti-inflammatory siRNA against interleukin-1β (siIL-1β) with more than 90% downregulation of IL-1β expression in LPS-activated macrophages. From in vivo studies, systemic administrated 1O₁₄-LNP/siRNA mainly distributed in liver and efficiently captured by hepatic macrophages without notable sign of toxicity. Furthermore, LPS/d-GalN-induced acute liver injury model treated with 1O₁₄-LNP/siIL-1β resulted in significant suppression of IL-1β expression and amelioration of liver tissue damage. These results demonstrate that the engineered ionizable LNP provides a powerful tool for siRNA delivery to macrophages and that the strategy of silencing of pro-inflammatory cytokines holds great potential for treating inflammatory diseases.

Vaccine Formulation Strategies and Challenges Involved in RNA Delivery for Modulating Biomarkers of Cardiovascular Diseases: A Race from Laboratory to Market

It has been demonstrated that noncoding RNAs have significant physiological and pathological roles. Modulation of noncoding RNAs may offer therapeutic approaches as per recent findings. Small RNAs, mostly long noncoding RNAs, siRNA, and microRNAs make up noncoding RNAs. Inhibiting or promoting protein breakdown by binding to 3' untranslated regions of target mRNA, microRNAs post-transcriptionally control the pattern of gene expression. Contrarily, long non-coding RNAs perform a wider range of tasks, including serving as molecular scaffolding, decoys, and epigenetic regulators. This article provides instances of long noncoding RNAs and microRNAs that may be a biomarker of CVD (cardiovascular disease). In this paper we highlight various RNA-based vaccine formulation strategies designed to target these biomarkers-that are either currently in the research pipeline or are in the global pharmaceutical market-along with the physiological hurdles that need to be overcome.