Fluoropolymers for intracellular and in vivo protein delivery

Fluoroamphiphiles for enhancing immune response of subunit vaccine against SARS-CoV-2

In recent decades, protein-based therapy has garnered valid attention for treating infectious diseases, genetic disorders, cancer, and other clinical requirements. However, safeguarding protein-based drugs against degradation and denaturation during processing, storage, and delivery poses a formidable challenge. Herein, we designed a novel fluoroamphiphiles polymer to deliver protein. Two different formulations of nanoparticles, cross-linked (CNP) and micelle (MNP) polymer, were prepared rationally by disulfide cross-linked and thin-film hydration techniques, respectively. Two prepared formulations were characterized for size, zeta potential, and morphology. The delivery efficacy of both in vitro and in vivo was also assessed. The in vitro findings demonstrated that both formulations effectively facilitated protein delivery into various cell lines. In vivo experiments revealed that intramuscular administration of the two formulations loaded with a SARS-CoV-2 recombinant receptor-binding domain (RBD) vaccine induced robust antibody responses in mice without adding another adjuvant. These results proved it may be employed as a safe and effective carrier for the delivery of subunit vaccines in vivo.

Unlocking nature's arsenal: Nanotechnology for targeted delivery of venom toxins in cancer therapy

AIM

The aim of the present review is to shed light on the nanotechnological approaches adopted to overcome the shortcomings associated with the delivery of venom peptides which possess inherent anti-cancer properties.

BACKGROUND

Venom peptides although have been reported to demonstrate anti-cancer effects, they suffer from several disadvantages such as in vivo instability, off-target adverse effects, limited drug loading and low bioavailability. This review presents a comprehensive compilation of different classes of nanocarriers while underscoring their advantages, disadvantages and potential to carry such peptide molecules for in vivo delivery. It also discusses various nanotechnological aspects such as methods of fabrication, analytical tools to assess these nanoparticulate formulations, modulation of nanocarrier polymer properties to enhance loading capacity, stability and improve their suitability to carry toxic peptide drugs.

CONCLUSION

Nanotechnological approaches bear great potential in delivering venom peptide-based molecules as anticancer agents by enhancing their bioavailability, stability, efficacy as well as offering a spatiotemporal delivery approach. However, the challenges associated with toxicity and biocompatibility of nanocarriers must be duly addressed.

PERSPECTIVES

The everlasting quest for new breakthroughs for safer delivery of venom peptides in human subjects is fuelled by unmet clinical needs in the current landscape of chemotherapy. In addition, exhaustive efforts are required in obtaining and purifying the venom peptides followed by designing and optimizing scale up technologies.

Fluorinated Organic Polymers for Cancer Drug Delivery

In the realm of cancer therapy, the spotlight is on nanoscale pharmaceutical delivery systems, especially polymer-based nanoparticles, for their enhanced drug dissolution, extended presence in the bloodstream, and precision targeting achieved via surface engineering. Leveraging the amplified permeation and retention phenomenon, these systems concentrate therapeutic agents within tumor tissues. Nonetheless, the hurdles of systemic toxicity, biological barriers, and compatibility with living systems persist. Fluorinated polymers, distinguished by their chemical idiosyncrasies, are poised for extensive biomedical applications, notably in stabilizing drug metabolism, augmenting lipophilicity, and optimizing bioavailability. Material science heralds the advent of fluorinated polymers that, by integrating fluorine atoms, unveil a suite of drug delivery merits: the hydrophobic traits of fluorinated alkyl chains ward off lipid or protein disruption, the carbon-fluorine bond's stability extends the drug's lifecycle in the system, and a lower alkalinity coupled with a diminished ionic charge bolsters the drug's ability to traverse cellular membranes. This comprehensive review delves into the utilization of fluorinated polymers for oncological pharmacotherapy, elucidating their molecular architecture, synthetic pathways, and functional attributes, alongside an exploration of their empirical strengths and the quandaries they encounter in both experimental and clinical settings.

Lipase and pH-responsive diblock copolymers featuring fluorocarbon and carboxyl betaine for methicillin-resistant staphylococcus aureus infections

The emergence of multidrug-resistant bacteria along with their resilient biofilms necessitates the development of creative antimicrobial remedies. We designed versatile fluorinated polymer micelles with surface-charge-switchable properties, demonstrating enhanced efficacy against Methicillin-Resistant Staphylococcus Aureus (MRSA) in planktonic and biofilm states. Polymethacrylate diblock copolymers with pendant fluorocarbon chains and carboxyl betaine groups were prepared using reversible addition-fragmentation chain transfer polymerization. Amphiphilic fluorinated copolymers self-assembled into micelles, encapsulating ciprofloxacin in their cores (CIP@FCBMs) for antibacterial and antibiofilm applications. As a control, fluorine-free copolymer micelles loaded with ciprofloxacin (CIP@BCBMs) were prepared. Although both CIP@FCBMs and CIP@BCBMs exhibited pH-responsive surface charges and lipase-triggered drug release, CIP@FCBMs exhibited powerful antimicrobial and antibiofilm activities in vitro and in vivo, attributed to superior serum stability, higher drug loading, enhanced fluorination-facilitated cellular uptake, and lipase-triggered drug release. Collectively, reversing surface charge, on-demand antibiotic release, and fluorination-mediated nanoparticles hold promise for treating bacterial infections and biofilms.

High-Throughput Screening of Surface Engineered Cyanine Nanodots for Active Transport of Therapeutic Antibodies into Solid Tumor

The successful delivery of therapeutic biomacromolecules into solid tumor holds great challenge due to their high resistance to penetrate through the complex tumor microenvironments. Here, active-transporting nanoparticles are harnessed to efficiently deliver biomacromolecular drugs into solid tumors through cell transcytosis. A series of molecularly precise cyanine 5-cored polylysine G5 dendrimers (Cy5 nanodots) with different peripheral amino acids (G5-AA) is prepared. The capability of these positively charged nanodots to induce cell endocytosis, exocytosis, and transcytosis is evaluated via fluorescence-based high-throughput screen. The optimized nanodots (G5-R) are conjugated with αPD-L1 (a therapeutic monoclonal antibody binding to programmed-death ligand 1) (αPD-L1-G5-R) to demonstrate the nanoparticle-mediated tumor active transport. The αPD-L1-G5-R can greatly enhance the tumor-penetration capability through adsorption-mediated transcytosis (AMT). The effectiveness of αPD-L1-G5-R is tested in treating mice bearing partially resected CT26 tumors, mimicking the local immunotherapy of residual tumors post-surgery in clinic. The αPD-L1-G5-R embedded in fibrin gel can efficiently mediate tumor cell transcytosis, and deliver αPD-L1 throughout the tumor, thereby enhancing immune checkpoint blockade, reducing tumor recurrence, and significantly prolonging the survival time. The active-transporting nanodots are promising platforms for efficient tumor delivery of therapeutic biomacromolecules.

Filamentous-Actin-Mimicking Nanoplatform for Enhanced Cytosolic Protein Delivery

Despite the potential of protein therapeutics, the cytosolic delivery of proteins with high efficiency and bioactivity remains a significant challenge owing to exocytosis and lysosomal degradation after endocytosis. Therefore, it is important to develop a safe and efficient strategy to bypass endocytosis. Inspired by the extraordinary capability of filamentous-actin (F-actin) to promote cell membrane fusion, a cyanine dye assembly-containing nanoplatform mimicking the structure of natural F-actin is developed. The nanoplatform exhibits fast membrane fusion to cell membrane mimics and thus enters live cells through membrane fusion and bypasses endocytosis. Moreover, it is found to efficiently deliver protein cargos into live cells and quickly release them into the cytosol, leading to high protein cargo transfection efficiency and bioactivity. The nanoplatform also results in the superior inhibition of tumor cells when loaded with anti-tumor proteins. These results demonstrate that this fusogenic nanoplatform can be valuable for cytosolic protein delivery and tumor treatment.

Investigating the Cytosolic Delivery of Proteins by Lipid Nanoparticles Using the Chloroalkane Penetration Assay

Protein therapeutics are an expanding area for research and drug development, and lipid nanoparticles (LNPs) are the most prominent nonviral vehicles for protein delivery. The most common methods for assessing protein delivery by LNPs include assays that measure the total amount of protein taken up by cells and assays that measure the phenotypic changes associated with protein delivery. However, assays for total cellular uptake include large amounts of protein that are trapped in endosomes or are otherwise nonfunctional. Assays for functional delivery are important, but the readouts are indirect and amplified, limiting the quantitative interpretation. Here, we apply an assay for cytosolic delivery, the chloroalkane penetration assay (CAPA), to measure the cytosolic delivery of a (-30) green fluorescent protein (GFP) fused to Cre recombinase (Cre(-30)GFP) fusion protein by LNPs. We compare these data to the data from total cellular uptake and functional delivery assays to provide a richer analysis of uptake and endosomal escape for LNP-mediated protein delivery. We also use CAPA for a screen of a small library of lipidoids, identifying those with a promising ability to deliver Cre(-30)GFP to the cytosol of mammalian cells. With careful controls and optimized conditions, we expect that CAPA will be a useful tool for investigating the rate, efficiency, and mechanisms of LNP-mediated delivery of therapeutic proteins.

Design of fluorinated stealth poly(ε-caprolactone) nanocarriers

The covalent functionalization of polymers with fluorinated moieties represents a promising strategy for the development of multimodal systems. Moreover, polymer fluorination often endows the resulting nanocarriers with improved colloidal stability in the biological environment. In this work, we developed fluorinated pegylated (PEG) biodegradable poly(ε-caprolactone) (PCL) drug nanocarriers showing both high colloidal stability and stealth properties, as well as being (19F)-Nuclear Magnetic Resonance (NMR) detectable. The optimized nanocarriers were obtained mixing a PEG-PCL block copolymer with a nonafluoro-functionalized PCL polymer. The role of PEGylation and fluorination on self-assembly and colloidal behavior of the obtained nanoparticles (NPs) was investigated, as well as their respective role on stealth properties and colloidal stability. To prove the feasibility of the developed NPs as potential 19F NMR detectable drug delivery systems, a hydrophobic drug was successfully encapsulated, and the maintenance of the relevant 19F NMR properties evaluated. Drug-loaded fluorinated NPs still retained a sharp and intense 19F NMR signal and good relaxivity parameters (i.e., T1 and T2 relaxation times) in water, which were not impaired by drug encapsulation.

Intracellular Protein Delivery: Approaches, Challenges, and Clinical Applications

Protein biologics are powerful therapeutic agents with diverse inhibitory and enzymatic functions. However, their clinical use has been limited to extracellular applications due to their inability to cross plasma membranes. Overcoming this physiological barrier would unlock the potential of protein drugs for the treatment of many intractable diseases. In this review, we highlight progress made toward achieving cytosolic delivery of recombinant proteins. We start by first considering intracellular protein delivery as a drug modality compared to existing Food and Drug Administration-approved drug modalities. Then, we summarize strategies that have been reported to achieve protein internalization. These techniques can be broadly classified into 3 categories: physical methods, direct protein engineering, and nanocarrier-mediated delivery. Finally, we highlight existing challenges for cytosolic protein delivery and offer an outlook for future advances.

Bioactive Phosphorus Dendrimers as a Universal Protein Delivery System for Enhanced Anti-inflammation Therapy

Nanocarrier-based cytoplasmic protein delivery offers opportunities to develop protein therapeutics; however, many delivery systems are positively charged, causing severe toxic effects. For enhanced therapeutics, it is also of great importance to design nanocarriers with intrinsic bioactivity that can be integrated with protein drugs due to the limited bioactivity of proteins alone for disease treatment. We report here a protein delivery system based on anionic phosphite-terminated phosphorus dendrimers with intrinsic anti-inflammatory activity. A phosphorus dendrimer termed AK-137 with optimized anti-inflammatory activity was selected to complex proteins through various physical interactions. Model proteins such as bovine serum albumin, ribonuclease A, ovalbumin, and fibronectin (FN) can be transfected into cells to exert their respective functions, including cancer cell apoptosis, dendritic cell maturation, or macrophage immunomodulation. Particularly, the constructed AK-137@FN nanocomplexes display powerful therapeutic effects in acute lung injury and acute gout arthritis models by integrating the anti-inflammatory activity of both the carrier and protein. The developed anionic phosphite-terminated phosphorus dendrimers may be employed as a universal carrier for protein delivery and particularly utilized to deliver proteins and fight different inflammatory diseases with enhanced therapeutic efficacy.

Fluoropolymer Nanoparticles Synthesized via Reversible-Deactivation Radical Polymerizations and Their Applications

Fluorinated polymeric nanoparticles (FPNPs) combine unique properties of fluorocarbon and polymeric nanoparticles, which has stimulated massive interest for decades. However, fluoropolymers are not readily available from nature, resulting in synthetic developments to obtain FPNPs via free radical polymerizations. Recently, while increasing cutting-edge directions demand tailored FPNPs, such materials have been difficult to access via conventional approaches. Reversible-deactivation radical polymerizations (RDRPs) are powerful methods to afford well-defined polymers. Researchers have applied RDRPs to the fabrication of FPNPs, enabling the construction of particles with improved complexity in terms of structure, composition, morphology, and functionality. Related examples can be classified into three categories. First, well-defined fluoropolymers synthesized via RDRPs have been utilized as precursors to form FPNPs through self-folding and solution self-assembly. Second, thermally and photoinitiated RDRPs have been explored to realize in situ preparations of FPNPs with varied morphologies via polymerization-induced self-assembly and cross-linking copolymerization. Third, grafting from inorganic nanoparticles has been investigated based on RDRPs. Importantly, those advancements have promoted studies toward promising applications, including magnetic resonance imaging, biomedical delivery, energy storage, adsorption of perfluorinated alkyl substances, photosensitizers, and so on. This Review should present useful knowledge to researchers in polymer science and nanomaterials and inspire innovative ideas for the synthesis and applications of FPNPs.

Potent gene delivery from fluorinated poly(β-amino ester) in adhesive and suspension difficult-to-transfect cells for apoptosis and ferroptosis

Tremendous efforts have been made to improve polymeric property in gene delivery performances, especially when obstacle of transferring gene construct into difficult-to-transfect cells occurs. Innovations in the area of fluorination and fluorinated compounds with biomedical potential in medicinal chemistry are believed to assist in the development of new therapeutics. Fluorine modified polymers have shown to navigate the gene transfection cellular barriers and promoted the transfection outcomes. Gene transfer into some liver cancer cells and human leukemia cells has always been a challenge. Here, by facile incorporation of a fluorine containing amine monomer, 1H,1H-undecafluorohexylamine, fluorinated poly(β-amino ester) (FPAE) was synthesized to significantly improve the transfection performance, achieving high transfection efficiency of 87% and 55% in two representative difficult-to-transfect cells, HepG2 and Molt-4, which were cultured in adhesive and suspension condition, respectively. However, the potency of Lipofectamine 3000 was very limited. More importantly, functional studies revealed that FPAE can dramatically outperform Lipofectamine 3000 in delivering Bcl-xL and PKCβII to either provide the protection against apoptosis or promote the ferroptosis in HepG2 cells. This work facilitates gene therapies by overcoming biological barriers for targeting difficult-to-transfect cells and disease models when medically necessary.

Engineered therapeutic proteins for sustained-release drug delivery systems

Proteins play a vital role in diverse biological processes in the human body, and protein therapeutics have been applied to treat different diseases such as cancers, genetic disorders, autoimmunity, and inflammation. Protein therapeutics have demonstrated their advantages, such as specific pharmaceutical effects, low toxicity, and strong solubility. However, several disadvantages arise in clinical applications, including short half-life, immunogenicity, and low permeation, leading to reduced drug effectiveness. The structure of protein therapeutics can be modified to increase molecular size, leading to prolonged stability and increased plasma half-life. Notably, the controlled-release delivery systems for the sustained release of protein drugs and preserving the stability of cargo proteins are envisioned as a potential approach to overcome these challenges. In this review, we summarize recent research progress related to structural modifications (PEGylation, glycosylation, poly amino acid modification, and molecular biology-based strategies) and promising long-term delivery systems, such as polymer-based systems (injectable gel/implants, microparticles, nanoparticles, micro/nanogels, functional polymers), lipid-based systems (liposomes, solid lipid nanoparticles, nanostructured lipid carriers), and inorganic nanoparticles exploited for protein therapeutics. STATEMENT OF SIGNIFICANCE: In this review, we highlight recent advances concerning modifying proteins directly to enhance their stability and functionality and discuss state-of-the-art methods for the delivery and controlled long-term release of active protein therapeutics to their target site. In terms of drug modifications, four widely used strategies, including PEGylation, poly amino acid modification, glycosylation, and genetic, are discussed. As for drug delivery systems, we emphasize recent progress relating to polymer-based systems, lipid-based systems developed, and inorganic nanoparticles for protein sustained-release delivery. This review points out the areas requiring focused research attention before the full potential of protein therapeutics for human health and disease can be realized.

Guanidyl-Rich Poly(β Amino Ester)s for Universal Functional Cytosolic Protein Delivery and Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) Cas9 Ribonucleoprotein Based Gene Editing

Protein therapeutics are highly promising for complex disease treatment. However, the lack of ideal delivery vectors impedes their clinical use, especially the carriers for in vivo delivery of functional cytosolic protein. In this study, we modified poly(β amino ester)s (PAEs) with a phenyl guanidine (PG) group to enhance their suitability for cytosolic protein delivery. The effects of the PG group on protein binding, cell internalization, protein function protection, and endo/lysosomal escape were systematically evaluated. Compared to the unmodified PAEs (L3), guanidyl rich PAEs (L3PG) presented superior efficiency of protein binding and protein internalization, mainly via clathrin-mediated endocytosis. In addition, both PAEs showed robust capabilities to deliver cytosolic proteins with different molecular weight (ranging from 30 to 464 kDa) and isoelectric points (ranging from 4.3 to 9), which were significantly improved in comparison with the commercial reagents of PULsin and Pierce Protein Transection Reagent. Moreover, L3PG successfully delivered Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) Cas9 ribonucleoprotein (RNP) into HeLa cells expressing green fluorescent protein (GFP) and achieved more than 80% GFP expression knockout. These results demonstrated that guanidyl modification on PAEs can enhance its capabilities for intracellular delivery of cytosolic functional proteins and CRISPR/Cas9 ribonucleoprotein. The guanidyl-rich PAEs are promising nonviral vectors for functional protein delivery and potential use in protein and nuclease-based gene editing therapies.

Preparation of Hyflon AD/Polypropylene Blend Membrane for Artificial Lung

A high-performance polypropylene hollow fiber membrane (PP-HFM) was prepared by using a binary environmentally friendly solvent of polypropylene as the raw material, adopting the thermally induced phase separation (TIPS) method, and adjusting the raw material ratio. The binary diluents were soybean oil (SO) and acetyl tributyl citrate (ATBC). The suitable SO/ATBC ratio of 7/3 was based on the size change of the L-L phase separation region in PP-SO/ATBC thermodynamic phase diagram. Through the characterization and comparison of the basic performance of PP-HFMs, it was found that with the increase of the diluent content in the raw materials, the micropores of outer surface of the PP-HFM became larger, and the cross section showed a sponge-like pore structure. The fluoropolymer, Hyflon ADx, was deposited on the outer surface of the hollow fiber membrane using a physical modification method of solution dipping. After modification, the surface pore size of the Hyflon AD40L modified membranes decreased; the contact angle increased to around 107°; the surface energy decreased to 17 mN·m^-1; and the surface roughness decreased to 17 nm. Hyflon AD40L/PP-HFMs also had more water resistance properties from the variation of wetting curve. For biocompatibility of the membrane, the adsorption capacity of the modified PP membrane for albumin decreased from approximately 1.2 mg·cm^-2 to 1.0 mg·cm^-2, and the adsorption of platelets decreased under fluorescence microscopy. The decrease in blood cells and protein adsorption in the blood prolonged the clotting time. In addition, the hemolysis rate of modified PP membrane was reduced to within the standard of 5%, and the cell survival rate of its precipitate was above 100%, which also indicated the excellent biocompatibility of fluoropolymer modified membrane. The improvement of hydrophobicity and blood compatibility makes Hyflon AD/PP-HFMs have the potential for application in membrane oxygenators.

Fluorous Tagged Peptides for Intracellular Delivery and Biomedical Imaging

Fluorous tagged peptides have shown promising features for biomedical applications such as drug delivery and multimodal imaging. The bioconjugation of fluoroalkyl ligands onto cargo peptides greatly enhances their proteolytic stability and membrane penetration via a proposed "fluorine effect". The tagged peptides also efficiently deliver other biomolecules such as DNA and siRNA into cells via a co-assembly strategy. The fluoroalkyl chains on peptides with antifouling properties enable efficient gene delivery in the presence of serum proteins. Besides intracellular biomolecule delivery, the amphiphilic peptides can be used to stabilized perfluorocarbon-filled microbubbles for ultrasound imaging. The fluorine nucleus on fluoroalkyls provides intrinsic probes for background-free magnetic resonance imaging. Labeling of fluorous tags with radionuclide 18 F also allows tracing the biodistribution of peptides via positron emission tomography imaging. This mini-review will discuss properties and mechanism of the fluorous tagged peptides in these applications.

Functional L-Arginine Derivative as an Efficient Vector for Intracellular Protein Delivery for Potential Cancer Therapy

The utilization of cytosolic protein delivery is a promising approach for treating various diseases by replacing dysfunctional proteins. Despite the development of various nanoparticle-based intracellular protein delivery methods, the complicated chemical synthesis of the vector, loading efficiency and endosomal escape efficiency of proteins remain a great challenge. Recently, 9-fluorenylmethyloxycarbonyl (Fmoc)-modified amino acid derivatives have been used to self-assemble into supramolecular nanomaterials for drug delivery. However, the instability of the Fmoc group in aqueous medium restricts its application. To address this issue, the Fmoc ligand neighboring arginine was substituted for dibenzocyclooctyne (DBCO) with a similar structure to Fmoc to obtain stable DBCO-functionalized L-arginine derivative (DR). Azide-modified triethylamine (crosslinker C) was combined with DR to construct self-assembled DRC via a click chemical reaction for delivering various proteins, such as BSA and saporin (SA), into the cytosol of cells. The hyaluronic-acid-coated DRC/SA was able to not only shield the cationic toxicity, but also enhance the intracellular delivery efficiency of proteins by targeting CD44 overexpression on the cell membrane. The DRC/SA/HA exhibited higher growth inhibition efficiency and lower IC₅₀ compared to DRC/SA toward various cancer cell lines. In conclusion, DBCO-functionalized L-arginine derivative represents an excellent potential vector for protein-based cancer therapy.

Recent Progress of Rational Modified Nanocarriers for Cytosolic Protein Delivery

Therapeutic proteins garnered significant attention in the field of disease treatment. In comparison to small molecule drugs, protein therapies offer distinct advantages, including high potency, specificity, low toxicity, and reduced carcinogenicity, even at minimal concentrations. However, the full potential of protein therapy is limited by inherent challenges such as large molecular size, delicate tertiary structure, and poor membrane penetration, resulting in inefficient intracellular delivery into target cells. To address these challenges and enhance the clinical applications of protein therapies, various protein-loaded nanocarriers with tailored modifications were developed, including liposomes, exosomes, polymeric nanoparticles, and nanomotors. Despite these advancements, many of these strategies encounter significant issues such as entrapment within endosomes, leading to low therapeutic efficiency. In this review, we extensively discussed diverse strategies for the rational design of nanocarriers, aiming to overcome these limitations. Additionally, we presented a forward-looking viewpoint on the innovative generation of delivery systems specifically tailored for protein-based therapies. Our intention was to offer theoretical and technical support for the development and enhancement of nanocarriers capable of facilitating cytosolic protein delivery.

Phosphocholine-Functionalized Zwitterionic Highly Branched Poly(β-amino ester)s for Cytoplasmic Protein Delivery

Proteins have tremendous potential for vaccine development and disease treatment, but multiple extracellular and intracellular biological barriers must be overcome before they can exert specific biological functions in the target tissue. The use of polymers as carriers would greatly improve their bioavailability and therapeutic efficiency. Nevertheless, effective protein packaging and cell membrane penetration without causing cytotoxicity is particularly challenging, due largely to the simultaneous distribution of positive and negative charges on protein surface. Here, phosphocholine-functionalized zwitterionic poly(β-amino ester)s, HPAE-D-(±), are developed for cytoplasmic protein delivery. The zwitterionic phosphocholine is capable of binding to both proteins and the cell membrane to facilitate protein packaging and nanoparticle cellular uptake. Compared to amine-functionalized HPAE-E-(+) and carboxylic acid-functionalized HPAE-C-(-), HPAE-D-(±) exhibits much higher cytoplasmic protein delivery efficiency and lower cytotoxicity. In addition, HPAE-D-(±) are readily degraded in aqueous solution. This strategy may be extended to other zwitterions and polymers, thus having profound implications for the development of safe and efficient protein delivery systems.

Thermo-pH-Sensitive Polymer Conjugated Glucose Oxidase for Tumor-Selective Starvation-Oxidation-Immune Therapy

Protein drugs are increasingly used as therapeutics for the treatment of cancer. However, their inherent drawbacks, such as poor stability, low cell membrane and tissue permeability, lack of tumor selectivity, and severe side effects, limit their wide applications in cancer therapy. Herein, screening of a thermo-pH-sensitive polymer-glucose oxidase conjugate that can controllably self-assemble into nanoparticles with improved stability is reported. The size, surface charge, and bioactivity of the conjugate can be tuned by adjustment of the solution temperature and pH. The cellular uptake, intracellular hydrogen peroxide generation, and tumor cell spheroid penetration of the conjugate are greatly enhanced under the acidic tumor microenvironment, leading to increased cytotoxicity to tumor cells. Upon a single intratumoural injection, the conjugate penetrates into the whole tumor tissue but hardly diffuses into the normal tissues, resulting in the eradication of the tumors in mice without perceivable side effects. Simultaneously, the conjugate induces a robust antitumor immunity to efficiently inhibit the growth of distant tumors, especially in combination with an immune checkpoint inhibitor. These findings provide a novel and general strategy to make multifunctional protein-polymer conjugates with responsiveness to the acidic tumor microenvironment for selective tumor therapy.

Histidine-based coordinative polymers for efficient intracellular protein delivery via enhanced protein binding, cellular uptake, and endosomal escape

Polymers are one of the most promising protein delivery carriers; however, their applications are hindered by low delivery efficacy owing to their undesirable performance in protein binding, cellular uptake and endosomal escape. Here, we designed a series of histidine-based coordinative polymers for efficient intracellular protein delivery. Coordination of metal ions such as Ni²⁺, Zn²⁺, and Cu²⁺ with histidine residues on a polymer greatly improved its performance in protein binding, complex stability, cellular uptake and endosomal escape, therefore achieving highly improved protein delivery efficacy. Among the coordinative polymers, the Zn²⁺-coordinated one exhibited the highest cellular uptake, while the Cu²⁺-coordinated one exhibited the highest endosomal escape. The Ni²⁺-coordinated polymer formed large-sized aggregates with cargo proteins and showed insufficient protein release after endocytosis. The results obtained in this study provided new insight into the development of coordinative polymer-based protein delivery systems.

Functionalized PAMAM constructed nanosystems for biomacromolecule delivery

Polyamidoamines (PAMAMs) are a class of dendrimer with monodispersity and controlled topology, which can deliver biologically active macromolecules (e.g., genes and proteins) to specific regions with high efficiency and minimum side effects. In detail, PAMAMs can be functionalized easily by core modification or surface amendment to encapsulate a wide range of biomacromolecules. Besides, self-assembled, cross-linked and hybrid PAMAMs with customized therapeutic purposes are developed as delivery vehicles, which makes PAMAMs promising for biomacromolecule therapy. In this review, we comprehensively summarize the application of PAMAMs in biomacromolecule delivery from the synthesis of functionalized PAMAM carriers to the development of PAMAM-based drug delivery systems. The underlying strategies for PAMAM functionalization and assembly are first systematically discussed, and then the current applications of PAMAMs for biomacromolecule delivery are reviewed. Finally, a brief perspective on the further applications of PAMAMs concludes, aiming to provide insights into developing PAMAM-based biomacromolecule delivery systems.

Fluorinated polyamidoamine dendrimer-mediated miR-23b delivery for the treatment of experimental rheumatoid arthritis in rats

In rheumatoid arthritis (RA), insufficient apoptosis of macrophages and excessive generation of pro-inflammatory cytokines are intimately connected, accelerating the development of disease. Here, a fluorinated polyamidoamine dendrimer (FP) is used to deliver miR-23b to reduce inflammation by triggering the apoptosis of as well as inhibiting the inflammatory response in macrophages. Following the intravenous injection of FP/miR-23b nanoparticles in experimental RA models, the nanoparticles show therapeutic efficacy with inhibition of inflammatory response, reduced bone and cartilage erosion, suppression of synoviocyte infiltration and the recovery of mobility. Moreover, the nanoparticles accumulate in the inflamed joint and are non-specifically captured by synoviocytes, leading to the restoration of miR-23b expression in the synovium. The miR-23b nanoparticles target Tab2, Tab3 and Ikka to regulate the activation of NF-κB pathway in the hyperplastic synovium, thereby promoting anti-inflammatory and anti-proliferative responses. Additionally, the intravenous administration of FP/miR-23b nanoparticles do not induce obvious systemic toxicity. Overall, our work demonstrates that the combination of apoptosis induction and inflammatory inhibition could be a promising approach in the treatment of RA and possibly other autoimmune diseases.

Lysosomal-mediated drug release and activation for cancer therapy and immunotherapy

The development of carrier systems that are able to transport and release therapeutics to target cells is an emergent strategy to treat cancer; however, they following endocytosis are usually trapped in the endo/lysosomal compartments. The efficacy of drug conjugates and nanotherapeutics relies critically on their intracellular drug release ability, for which advanced systems responding to the unique lysosomal environment such as acidic pH and abundant enzymes (e.g. cathepsin B, sulfatase and β-glucuronidase) or equipped with photochemical internalization property have been energetically pursued. In this review, we highlight the recent designs of smart systems that promote efficient lysosomal release and/or escape of anticancer agents including chemotherapeutics (e.g. doxorubicin, platinum, chloroquine and hydrochloroquine) and biotherapeutics (e.g. proteins, siRNA, miRNA, mRNA and pDNA) to cancer cells or immunotherapeutic agents (e.g. antigens, mRNA and immunoadjuvants) to antigen-presenting cells (APCs), thereby boosting cancer therapy and immunotherapy. Lysosomal-mediated drug release presents an appealing approach to develop innovative cancer therapeutics and immunotherapeutics.

Fluorination Effects on the Drug Delivery Property of Cylindrical Polymer Brushes

Fluorination has been widely applied to improving the properties of small-molecule drugs. However, relatively little is known about the effects of fluorination on the drug delivery property of nanomaterials. In this paper, we synthesized a fluoroalkane-modified cylindrical polymer brush (CPB) BCPB-F and an alkane-modified analogue BCPB-H. Doxorubicin (DOX) was used as a model drug and was loaded onto the CPBs through a pH-responsive acylhydrazone linkage. High drug loading and good water solubility were achieved. The in vitro and in vivo experiments suggested that fluorination played an important role in improving the cellular uptake, blood circulation, tissue permeability, and tumor targeting ability of CPBs. Due to these superiorities, the DOX-loaded BCPB-F exhibited excellent antitumor efficacy and eradicated the tumors of mice after five-dose treatments. The well-defined structures of the drug-free and drug-loaded CPBs guaranteed the accuracy of the results. This work demonstrates that fluorination is a promising strategy to improve the overall properties of nanomedicines.

Redox-responsive carrier based on fluorinated gemini amphiphilic polymer for combinational cancer therapy

Polymeric micelle has emerged as an efficient implement to overcome the shortcomings of conventional cancer chemotherapy due to its superior solubility of hydrophobic drugs and less side effects of drugs. However, insufficient dilution resistance and ordinary therapeutic effect severely restrict the further translation of current drug-loaded polymeric micelles. Here, we showed that well-defined G-Fn (n = 5, 9, 13) polymeric micelles possessed excellent capabilities as a drug carrier in light of high drug loading content, high stability and precise drug release combined with wonderful endocytosis efficiency to tumors. The representative G-F13 exhibited an excellent dilution resistance, outstanding high drug loading content (22 wt%) and drug loading efficiency (82%), which might be attributed to the extremely low critical micelle concentration conferred by its special Gemini structure and the superhydrophobicity of the fluorocarbon chain. Furthermore, the "cross-linked" internal fluoride membrane consisted of the two chains of the Gemini structure made G-F13 stable even after 24 h of incubation in 10% fetal bovine serum (FBS). The camptothecin (CPT) release was selectively triggered by glutathione (GSH) and H₂O₂, reaching 75% and 85% after 24 h respectively, in which only 15% of drugs leak under physiological conditions. The CCK-8 assays of Hela cells showed that CPT-loaded G-F13 micelles had high cell compatibility (200 μg/mL, 93% cell viability, 48 h) and high cancer cytotoxicity (IC50 0.1 μg/mL). Notably, a tenfold lower dosage of loaded CPT had an higher tumor growth inhibition than the free CPT. This result was attributed to the combined treatment of fluorinated drug carriers were more likely to penetrate the cell membrane to enter tumor cells, the cytotoxicity of selenic acid generated after the oxidation of G-F13 and the large amounts of CPT after redox release. Excellent physical and chemical properties as well as good therapeutic effects reveal that G-F13 can act as a promising drug carrier to widely use in cancer chemotherapy.

In vivo fate and intracellular trafficking of vaccine delivery systems

With the pandemic of severe acute respiratory syndrome coronavirus 2, vaccine delivery systems emerged as a core technology for global public health. Given that antigen processing takes place inside the cell, the intracellular delivery and trafficking of a vaccine antigen will contribute to vaccine efficiency. Investigations focusing on the in vivo behavior and intracellular transport of vaccines have improved our understanding of the mechanisms relevant to vaccine delivery systems and facilitated the design of novel potent vaccine platforms. In this review, we cover the intracellular trafficking and in vivo fate of vaccines administered via various routes and delivery systems. To improve immune responses, researchers have used various strategies to modulate vaccine platforms and intracellular trafficking. In addition to progress in vaccine trafficking studies, the challenges and future perspectives for designing next-generation vaccines are discussed.

Engineered EGCG-Containing Biomimetic Nanoassemblies as Effective Delivery Platform for Enhanced Cancer Therapy

Nano-based immunotherapy of therapeutic biomolecules is attractive but tremendously hampered by the poor delivery efficiency. This study reports a novel delivery system of fluorinated-coordinative-epigallocatechin gallate (EGCG), referring as FEGCG/Zn, through the integration of fluorination and zinc ions (Zn²⁺ ) into EGCG. The robust therapeutics of FEGCG/Zn are measured in terms of the regulating effect on programmed cell death ligand 1 (PD-L1), the effective delivery of diverse biomolecules, and the hitchhiking ability using living cells. Taking small interfering RNA of PD-L1 (siPD-L1) and erythrocytes as an example, the fabricated biomimetic system achieves excellent siPD-L1 delivery and further improves siPD-L1 accumulation in tumors. Finally, the combination of FEGCG/Zn and siPD-L1 promotes antitumor immunotherapy through alleviation of T cells exhaustion by regulating PD-L1 expression in tumor cells. The results demonstrate that FEGCG/Zn substantially regulates PD-L1 expression and improves immune-biomolecule delivery by forming biomimetic nanoassemblies, offering a versatile platform for cancer immunotherapy.

A general carbon dot-based platform for intracellular delivery of proteins

The shortcomings of proteins, such as poor stability in biological environments, the impermeability of the membrane and the susceptibility to enzymolysis, restrict their potential applications. Therefore, constructing universal nanocarriers for intracellular delivery of a variety of proteins remains a great challenge. In this work, gallic acid (GA) and L-lysine were used as starting materials to synthesize carbon dots (CDs). The CDs were used as carriers to interact with bovine serum albumin (BSA), enhanced green fluorescent protein (EGFP) and glucose oxidase (GOx) via supramolecular interaction to construct CDs-protein nanocomposites CDs-BSA, CDs-EGFP and CDs-GOx. Furthermore, CDs-EGFP and CDs-GOx can achieve intracellular protein delivery and maintain 89% of the biological activity of GOx. In this work, the latency of CDs is projected as a universal platform for effective intracellular delivery of proteins.

Fluorination Promotes the Cytosolic Delivery of Genes, Proteins, and Peptides

The cytosolic delivery of biomolecules such as genes, proteins, and peptides is of great importance for biotherapy but usually limited by multiple barriers during the process. Cell membrane with high hydrophobic character is one of the representative biological barriers for cytosolic delivery. The introduction of hydrophobic ligands such as aliphatic lipids onto materials or biomolecules could improve their membrane permeability. However, these ligands are lipophilic and tend to interact with the phospholipids in the membrane as well as serum proteins, which may hinder efficient intracellular delivery. To solve this issue, our research group proposed the use of fluorous ligands with both hydrophobicity and lipophobicity as ideal alternatives to aliphatic lipids to promote cytosolic delivery.In our first attempt, fluorous ligands were conjugated onto cationic polymers to increase their gene delivery efficacy. The fluorination dramatically increased the gene delivery performance at low polymer doses. In addition, the strategy greatly improved the serum tolerance of cationic polymers, which is critical for efficient gene delivery in vivo. Besides serum tolerance, mechanism studies revealed that fluorination increases multiple steps such as cellular uptake and endosomal escape. Fluorination also allowed the assembly of low-molecular-weight polymers and achieved highly efficient gene delivery with minimal material toxicity. The method showed robust efficiency for polymers, including linear polymers, branched polymers, dendrimers, bola amphiphilies, and dendronized polymers.Besides gene delivery, fluorinated polymers were also used for intracellular protein delivery via a coassembly strategy. For this purpose, two lead fluoropolymers were screened from a library of amphiphilic materials. The fluoropolymers are greatly superior to their nonfluorinated analogues conjugated with aliphatic lipids. The fluorous lipids are beneficial for polymer assembly and protein encapsulation, reduced protein denaturation, facilitated endocytosis, and decreased polymer toxicity compared to nonfluorinated lipids. The materials exhibited potent efficacy in therapeutic protein and peptide delivery to achieve cancer therapy and were able to fabricate a personalized nanovaccine for cancer immunotherapy. Finally, the fluorous lipids were directly conjugated to peptides via a disulfide bond for cytosolic peptide delivery. Fluorous lipids drive the assembly of cargo peptides into uniform nanoparticles with much improved proteolytic stability and promote their delivery into various types of cells. The delivery efficacy of this strategy is greatly superior to traditional techniques such as cell-penetrating peptides both in vitro and in vivo. Overall, the fluorination techniques provide efficient and promising strategies for the cytosolic delivery of biomolecules.

Strategies for High-Efficiency Mutation Using the CRISPR/Cas System

Clustered regularly interspaced short palindromic repeats (CRISPR)-associated systems have revolutionized traditional gene-editing tools and are a significant tool for ameliorating gene defects. Characterized by high target specificity, extraordinary efficiency, and cost-effectiveness, CRISPR/Cas systems have displayed tremendous potential for genetic manipulation in almost any organism and cell type. Despite their numerous advantages, however, CRISPR/Cas systems have some inherent limitations, such as off-target effects, unsatisfactory efficiency of delivery, and unwanted adverse effects, thereby resulting in a desire to explore approaches to address these issues. Strategies for improving the efficiency of CRISPR/Cas-induced mutations, such as reducing off-target effects, improving the design and modification of sgRNA, optimizing the editing time and the temperature, choice of delivery system, and enrichment of sgRNA, are comprehensively described in this review. Additionally, several newly emerging approaches, including the use of Cas variants, anti-CRISPR proteins, and mutant enrichment, are discussed in detail. Furthermore, the authors provide a deep analysis of the current challenges in the utilization of CRISPR/Cas systems and the future applications of CRISPR/Cas systems in various scenarios. This review not only serves as a reference for improving the maturity of CRISPR/Cas systems but also supplies practical guidance for expanding the applicability of this technology.

Phase-separating peptides for direct cytosolic delivery and redox-activated release of macromolecular therapeutics

Biomacromolecules are highly promising therapeutic modalities to treat various diseases. However, they suffer from poor cellular membrane permeability, limiting their access to intracellular targets. Strategies to overcome this challenge often employ nanoscale carriers that can get trapped in endosomal compartments. Here we report conjugated peptides that form pH- and redox-responsive coacervate microdroplets by liquid-liquid phase separation that readily cross the cell membrane. A wide range of macromolecules can be quickly recruited within the microdroplets, including small peptides, enzymes as large as 430 kDa and messenger RNAs (mRNAs). The therapeutic-loaded coacervates bypass classical endocytic pathways to enter the cytosol, where they undergo glutathione-mediated release of payload, the bioactivity of which is retained in the cell, while mRNAs exhibit a high transfection efficiency. These peptide coacervates represent a promising platform for the intracellular delivery of a large palette of macromolecular therapeutics that have potential for treating various pathologies (for example, cancers and metabolic diseases) or as carriers for mRNA-based vaccines.

Potential-Independent Intracellular Drug Delivery and Mitochondrial Targeting

In this study, two types of the fluoroamphiphile analogs were synthesized and self-assembled into the "core-shell" micellar nanocarriers for intracellular delivery and organelle targeting. Using the fluorescent dyes or vitamin E succinate as the cargo, the drug delivery and targeting capabilities of the fluoroamphiphiles and their micelles were evaluated in the cell lines, tumor cell spheroids, and tumor-bearing mice. The "core-fluorinated" micelles exhibited favorable physicochemical properties and improved the cellular uptake of the cargo by around 20 times compared to their "shell-fluorinated" counterparts. The results also indicated that the core-fluorinated micelles underwent an efficient clathrin-mediated endocytosis and a rapid endosomal escape thereafter. Interestingly, the internalized fluoroamphiphile micelles preferentially accumulated in mitochondria, by which the efficacy of the loaded vitamin E succinate was boosted both in vitro and in vivo. Unlike the popularly used cationic mitochondrial targeting ligands, as a charge-neutral nanocarrier, the fluoroamphiphiles' mitochondrial targeting was potential independent. The mechanism study suggested that the strong binding affinity with the phospholipids, particularly the cardiolipin, played an important role in the fluoroamphiphiles' mitochondrial targeting. These charge-neutral fluoroamphiphiles might have great potential to be a simple and reliable tool for intracellular drug delivery and mitochondrial targeting.

Precise gene delivery systems with detachable albumin shell remodeling dysfunctional microglia by TREM2 for treatment of Alzheimer's disease

Intervention of the over-activated microglia-aggravated neuroinflammation represents a promising therapeutic strategy for Alzheimer's disease (AD). Upregulation of triggering receptor expressed on myeloid cells-2 (TREM2) attenuates the neuroinflammatory processes and normalizes the dysfunctional microglia. However, Trem2-gene therapy for AD by the effective non-invasive delivery systems is unexploited. Herein, we report the microglia-targeted gene delivery systems (PHSA@PF/pTREM2) composed of a core of fluorinated polyethylenimine condensing the TREM2-encoding plasmid (PF/pTREM2) and a shell of human serum albumin conjugated with both cis-aconitic anhydride and neural cell adhesion molecule-mimetic peptide P2 (PHSA). Thanks to the shedding effect of the albumin coated, PHSA@PF/pTREM2 exhibit prolonged blood circulation and low cytotoxicity. PHSA@PF/pTREM2 achieve brain accumulation as high as 2.17% injected dose per gram of brain and the microglial-targeting effect (targeting specificity of 41.9%) via the systemic administration. The nanocomplexes can be detached PHSA-shell in the acidic endo-lysosomes via the cleavage of cis-aconitic amide bond, resulting in PF/pTREM2 exposure for efficient endo-lysosomal escape and gene transfection. PHSA@PF/pTREM2 upregulate the TREM2 level and regulate microglial polarization toward M2-phenotype for remodeling the inflammatory microenvironment and enhanced Aβ clearance, leading to an improvement of cognitive performance in APP/PS1 mice. This work provides a promising gene delivery platform to reverse dysfunctional microglia for AD therapy.

Fluorinated paclitaxel prodrugs for potentiated stability and chemotherapy

Robust colloidal stability is an essential prerequisite for effective drug delivery. Herein, a series of fluorinated paclitaxel prodrugs bridged with redox-responsive linkages were synthesized, and the effect of fluorination on the assembly behavior and physiological stability was investigated. The 17-fluorinated ethanol-modified paclitaxel prodrug could self-assemble into stable nanoparticles without the addition of any surfactants. Fluorinated paclitaxel prodrug nanoparticles possessed potent cytotoxicity toward cancer cells and superior antitumor activity. This study offers a universal fluorination approach to improve drug delivery efficacy by enhancing the self-assembly capability and improving the colloidal stability of prodrugs for potentiating chemotherapy.

A manganese (II)-based coordinative dendrimer with robust efficiency in intracellular peptide delivery

Peptides have gained increasing interests as drug candidates in modern pharmaceutical industry, however, the development of peptide drugs acting on intracellular targets is limited due to their membrane impermeability. Here, we reported the use of metal-terpyridine based coordinative dendrimer for cytosolic peptide delivery. Among the investigated transition metal ions, Mn²⁺-coordinated polymer showed the highest delivery efficiency due to balanced peptide binding and release. It showed robust efficiency in the delivery of peptides with different charge property and hydrophobicity into various primary cells. The efficiency of Mn²⁺-terpyridine based polymer is superior to cell penetrating peptides such as oligoarginines. The material also delivered an autophagy-inducing peptide derived from Beclin-1 into cells and efficiently induced autophagy in the cells. This study provides a promising alternative to cell penetrating peptides for cytosolic peptide delivery.

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A Mn²⁺/terpyridine based polymer is rationally designed for cytosolic peptide delivery.

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The polymer shows robust efficiency in the delivery of 22 peptides with different properties into various primary cells.

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The polymer delivers an autophagy-inducing peptide derived from Beclin-1 into cells and efficiently induces autophagy.

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This study provides a promising alternative to cell penetrating peptides for cytosolic peptide delivery.

Design of Polymeric Carriers for Intracellular Peptide Delivery in Oncology Applications

In recent decades, peptides, which can possess high potency, excellent selectivity, and low toxicity, have emerged as promising therapeutics for cancer applications. Combined with an improved understanding of tumor biology and immuno-oncology, peptides have demonstrated robust antitumor efficacy in preclinical tumor models. However, the translation of peptides with intracellular targets into clinical therapies has been severely hindered by limitations in their intrinsic structure, such as low systemic stability, rapid clearance, and poor membrane permeability, that impede intracellular delivery. In this Review, we summarize recent advances in polymer-mediated intracellular delivery of peptides for cancer therapy, including both therapeutic peptides and peptide antigens. We highlight strategies to engineer polymeric materials to increase peptide delivery efficiency, especially cytosolic delivery, which plays a crucial role in potentiating peptide-based therapies. Finally, we discuss future opportunities for peptides in cancer treatment, with an emphasis on the design of polymer nanocarriers for optimized peptide delivery.

A pH-Responsive Phase-Transition Polymer with High Serum Stability in Cytosolic Protein Delivery

Polymer-mediated intracellular protein delivery systems are important for the development of protein-based biotechnologies and therapeutics. However, intracellular delivery of cargo proteins in the presence of serum remains challenging due to competitive binding of serum proteins with the polymers. Here, we reported a dendrimer engineered with a high density of 4-diethylaminophenyl groups on the surface to address this issue. The dendrimer showed a pH-responsive phase-transition behavior and could assemble with cargo proteins into stable nanoparticles in serum solutions. It efficiently delivered cargo proteins into living cells, and exhibited a pH-responsive disassembly behavior after cell internalization. As a result, various cargo proteins were delivered into the cytosol of living cells with maintained bioactivity. This study provided a convenient and efficient strategy to design polymers with high serum-tolerance in cytosolic protein delivery.

Fluorinated chitosan-mediated intracellular catalase delivery for enhanced photodynamic therapy of oral cancer

A pH-responsive fluorinated chitosan-chlorin e6 (FC-Ce6) was employed here for the intracellular delivery of catalase to relieve the hypoxic micro-environment. Upon simple mixing, FC-Ce6 and catalase co-assemble to form stable nanoparticles, which show a greatly improved cross-membrane penetration capacity compared with catalase alone or nonfluorinated CS-Ce6/catalase nanoparticles. Under catalase catalysis, a high concentration of intracellular H2O2 can be transformed into O2. Upon irradiation, due to the continuous formation of cytotoxic singlet oxygen (1O2), our nanoparticles showed superior anti-cancer activity in contrast to free Ce6 and nonfluorinated CS-Ce6/catalase nanoparticles. Our study proposes an effective intracellular catalase delivery system to overcome hypoxia for enhanced PDT against oral cancer.

Nanomedicines for the treatment of glaucoma: Current status and future perspectives

Glaucoma is the global leading cause of irreversible blindness. It is a chronic progressive disorder and, therefore, often requires long-term management with drugs on patients' discretion. However, there is a shortage of antiglaucoma drugs in the current market due to their low bioavailability. This is because there are multiple biological barriers of the human eyes, thereby leading to increased demands for frequent dosage regimen per day of these drugs, which could result in concomitant side effects and eventually reduced patient compliance. Recently, nanomedicines have become optimized alternatives to conventional ophthalmic formulations due to advantages of improved barrier permeability, sustained drug release, tissue targeting, and lowered systemic absorption of instilled medications. These merits provide the active ingredients in these nanomedicines an effective manner to reach the ideal concentrations at sites of damaged nerves, offering a promising platform for neuroprotective treatment of these conditions. In this study, nanomedicines and nanomedicine-based novel strategies for pharmacotherapy of glaucoma were reviewed, including liposomes, niosomes, nanoparticles, and dendrimers. This article intends to offer a comprehensive review of frontier progresses as well as hotspots and issues that appeared in the field of nanomedicines, which may enable a practical flourish in the future. STATEMENT OF SIGNIFICANCE: Recent novel pharmaceutical strategies toward glaucoma, a chronic blinding ocular disease that currently requires frequent daily dosage regimen, based on nanomedicines and nanomaterials have been comprehensively reviewed in this manuscript. The collection of field hotspots and issues in the late years should offer a quick grasp of the general concept and up-to-date threads upon the refinement of existing treatment patterns for glaucoma. Meanwhile, the Conclusion and Future Perspective section given at the end of the text brings out the possible shortages and opinions in terms of ideal research direction, which hopefully could facilitate a future practical flourish in the area.

Regulation of Proteins to the Cytosol Using Delivery Systems with Engineered Polymer Architecture

Intracellular protein delivery enables selective regulation of cellular metabolism, signaling, and development through introduction of defined protein quantities into the cell. Most applications require that the delivered protein has access to the cytosol, either for protein activity or as a gateway to other organelles such as the nucleus. The vast majority of delivery vehicles employ an endosomal pathway however, and efficient release of entrapped protein cargo from the endosome remains a challenge. Recent research has made significant advances toward efficient cytosolic delivery of proteins using polymers, but the influence of polymer architecture on protein delivery is yet to be investigated. Here, we developed a family of dendronized polymers that enable systematic alterations of charge density and structure. We demonstrate that while modulation of surface functionality has a significant effect on overall delivery efficiency, the endosomal release rate can be highly regulated by manipulating polymer architecture. Notably, we show that large, multivalent structures cause slower sustained release, while rigid spherical structures result in rapid burst release.

Fluoropolymer-Mediated Intracellular Delivery of miR-23b for the Osteocyte Differentiation in Osteoblasts

Emerging evidence suggests that microRNAs (miRNAs) play key roles in the regulation of multiple biological processes, including the differentiation of osteoblasts. Although miRNA-based gene therapy holds immense potential in the treatment of a variety of diseases, the intracellular delivery of miRNA remains challenging owing to the lack of efficient and safe gene carriers. In this study, a fluoropolymer (FP) is constructed through the modification of polyamidoamine (PAMAM) using heptafluorobutyric anhydride and then is used as a carrier for miR-23b transfection to induce osteocyte differentiation of osteoblasts. The derivative FP is found to facilitate miR-23b transfection due to its favorable endosomal escape from the "proton sponge" effect. Compared to PAMAM/miR-23b, the FP/miR-23b nanocomplex efficiently promotes the differentiation of osteoblasts and formation of calcified nodules, attributable to enhanced expression of various osteogenesis genes (runt-related transfection factor 2 [RUNX2], alkaline phosphatase [ALP], osteopontin [OPN], and osteocalcin [OCN]). Thus, FP-mediated miR-23b transfection may be used as an effective strategy to facilitate osteogenic differentiation.