Chitosan for gene delivery: Methods for improvement and applications

Advances in the application of hydrogel adhesives for wound closure and repair in abdominal digestive organs

The abdominal cavity houses the majority of the digestive system organs, which frequently suffer from diseases with limited responsiveness to pharmacological treatments, such as bleeding, perforation, cancer, and mechanical obstruction. Invasive procedures, including endoscopy and surgery, are typically employed to manage these conditions. Currently, sutures and staplers remain the gold standard for internal wound closure. However, these methods inevitably cause secondary tissue damage. Unlike superficial organs such as the skin, the abdominal cavity presents a relatively confined environment where postoperative complications tend to be more severe. To achieve wound closure and repair, hydrogel adhesives have garnered attention due to their minimal invasiveness, robust sealing, and ease of application. Nonetheless, the application of hydrogel adhesives within the abdominal cavity faces several challenges, including adhesion in moist environments, selective adhesion, and resistance to acids and digestive enzymes. To date, there has been no comprehensive review focused on the use of hydrogel adhesives for wound closure in abdominal digestive organs. This review introduces the design principles of hydrogel adhesives tailored for abdominal organs and provides a detailed overview of recent advances in their applications for esophageal endoscopic submucosal dissection, gastric perforation, hepatic bleeding, pancreatic leakage, and intestinal anastomotic leakage. Additionally, the current challenges and future directions of hydrogel adhesives are discussed. This review aims to provide valuable insights for the development of next-generation hydrogel adhesives for wound closure and repair in abdominal digestive organs.

Chitosan-Based Gel Development: Extraction, Gelation Mechanisms, and Biomedical Applications

Chitosan (CS), a versatile biopolymer obtained through the deacetylation of chitin, has gained significant interest in biomedical and pharmaceutical applications due to its biocompatibility, biodegradability, and unique gel-forming capabilities. This review comprehensively analyzes CS-based gel development, covering its extraction from various natural sources, gelation mechanisms, and biomedical applications. Different extraction methods, including chemical, biological, and green techniques, are discussed regarding efficiency and sustainability. The review explores the physicochemical properties of CS that influence its gelation behavior, highlighting various gelation mechanisms such as physical, ionic, and chemical cross-linking. Recent advances in gel formation, including Schiff base reactions, Diels-Alder click chemistry, and thermosensitive gelation, have expanded the applicability of CS hydrogels. Furthermore, CS-based gels have demonstrated potential in wound healing, tissue engineering, drug delivery, and antimicrobial applications, offering controlled drug release, enhanced biocompatibility, and tunable mechanical properties. The incorporation of nanomaterials, bioactive molecules, and functional cross-linkers has further improved hydrogel performance. The current review underscores the growing significance of CS-based gels as innovative biomaterials in regenerative medicine and pharmaceutical sciences.

Nanoparticle-Based gene therapy strategies in retinal delivery

Vision loss and blindness are significant issues in both developed and developing countries. There are a wide variety of aetiologies that can cause vision loss, which are outlined in this review. Although treatment has significantly improved over time for some conditions, nearly half of all people with vision impairment are left untreated. Gene delivery is an emerging field that may assist with the treatment of some of these difficult to manage forms of vision loss. Here we review how a component of nanotechnology-based, non-viral gene delivery systems are being applied to help resolve vision impairment. This review focuses on the use of lipid and polymer nanoparticles, and quantum dots as gene delivery vectors to the eye. Finally, we also highlight some emerging technologies that may be useful in this discipline.

Physicochemical characteristics of chitosan molecules: Modeling and experiments

Chitosan, a biocompatible polysaccharide, finds a wide range of applications, inter alia as an antimicrobial agent, stabilizer of food products, cosmetics, and in the targeted delivery of drugs and stem cells. This work represents a comprehensive review of the properties of chitosan molecule and its aqueous solutions uniquely combining theoretical modeling and experimental results. The emphasis is on physicochemical aspects which were sparsely considered in previous reviews. Accordingly, in the first part, the explicit solvent molecular dynamics (MD) modeling results characterizing the conformations of chitosan molecule, the contour length, the chain diameter and the density are discussed. These MD data are used to calculate several parameters for larger chitosan molecules using a hybrid approach based on continuous hydrodynamics. The dependencies of hydrodynamic diameter, frictional ratio, radius of gyration, and intrinsic viscosity on the molar mass of molecules are presented and discussed. These theoretical predictions, comprising useful analytical solutions, are used to interpret and rationalize the extensive experimental data acquired by advanced experimental techniques. In the final part, the molecule charge, acid-base, and electrokinetic properties, comprising the electrophoretic mobility and the zeta potential, are reviewed. Future research directions are defined and discussed.

Interpolyelectrolyte complexes of in vivo produced dsRNA with chitosan and alginate for enhanced plant protection against tobacco mosaic virus

We developed a formulation of long double-stranded RNA (dsRNA) using interpolyelectrolyte complexes (IPECs) composed of the biopolymers chitosan and alginate, in order to protect the dsRNA from biotic and abiotic factors. Our primary objectives were to enhance stability of dsRNA against environmental nucleases and, secondarily, to mitigate the negative charge of the dsRNA, which may promote foliar uptake. Our approach relies on submicron particles with adjustable surface charge being either positive or negative. Following this approach, we obtained a high encapsulation efficiency of 94 %. Subsequently, we investigated the influence of the charge ratio and total polymer content on the size, size distribution and ζ-potential of the IPECs. We discovered that formulating at low polymer concentrations ≤0.05 g/L with charge ratios of ≤0.9 (+/-) and ≥ 1.25 (+/-), respectively, produced <100 nm particles. Furthermore, the IPEC formulation protected dsRNA from enzymatic degradation by RNase III and micrococcal nuclease. In addition, we observed outstanding protection of formulated dsRNA from heat degradation. Experiments on Nicotiana benthamiana plants showed that formulated dsRNA offered protection against tobacco mosaic virus. In essence, this formulation demonstrates versatility for the production of IPECs with customizable size, surface charge, and nucleic acid content.

Synthesis of poly[2-(dimethylamino)ethyl methacrylate] grafting from cellulose nanocrystals for DNA complexation employing a 3D-twisted cross-sectional microchannel microfluidic device

Developing effective and safe non-viral gene vectors poses a challenge in gene therapy. A promising strategy emerged addressing this challenge, involving a synergistic approach combining biopolymers and cationic synthetic polymers to enhance gene delivery systems. In this study, for the first time, poly[2-(dimethylamino)ethyl methacrylate] (PDMAEMA) was grafted from cellulose nanocrystals (CNC) using metal-free organocatalyzed atom-transfer radical polymerization (O-ATRP). The synthesis was confirmed through morphological, spectroscopic, and thermal analysis. The reaction achieved a 34 % monomer conversion and 15 % grafting, resulting in a CNC-g-PDMAEMA copolymer with impressive responsiveness to pH and temperature. Furthermore, CNC-g-PDMAEMA was utilized to obtain copolymer/pDNA polyplexes using a microfluidic device, providing a practical and efficient method for producing uniform, stable, and reproducible gene delivery systems. These polyplexes had sizes around 160 nm and a low PDI (<0.250). As a proof of concept, preliminary cell viability and transfection assays were conducted to demonstrate the biomaterial's applicability. These findings suggest that polyplexes (N/P = 15) at a 10 μg/mL concentration may serve as an upper limit threshold and a starting point for further in vivo studies. In summary, this research advances the development of gene delivery platforms through innovative and straightforward synthesis methods, opening up potential applications in gene therapy.

Enhancing photodynamic and radionuclide therapy by small interfering RNA (siRNA)-RAD51 transfection via self-emulsifying delivery systems (SNEDDS)

BACKGROUND AIMS

Gene-silencing by small interfering RNA (siRNA) is an attractive therapy to regulate cancer death, tumor recurrence or metastasis. Because siRNAs are easily degraded, it is necessary to develop transport and delivery systems to achieve efficient tumor targeting. Self-nanoemulsifying systems (SNEDDS) have been successfully used for pDNA transport and delivery, so they may be useful for siRNA. The aim of this work is to introduce siRNA-RAD51 into a SNEDDS prepared with Phospholipon-90G, Labrafil-M1944-CS and Cremophor-RH40 and evaluate its efficacy in preventing homologous recombination of DNA double-strand breaks caused by photodynamic therapy (PDT) and ionizing radiation (IR).

METHODS

The siRNA-RAD51 was loaded into SNEDDS using chitosan. Transfection capacity was estimated by comparison with Lipofectamine-2000.

RESULTS

SNEDDS(siRNA-RAD51) induced gene silencing effect on the therapies evaluated by cell viability and clonogenic assays using T47D breast cancer cells.

CONCLUSIONS

SNEDDS(siRNA-RAD51) shown to be an effective siRNA-delivery system to decrease cellular resistance in PDT or IR.

Chitosan-based nanoarchitectures for siRNA delivery in cancer therapy: A review of pre-clinical and clinical importance

The gene therapy has been developed into a new cancer treatment option. Now that we know which molecular components contribute to carcinogenesis, we may use gene therapy to target particular signalling pathways in cancer treatment. Problems with gene therapy include genetic tool degradation in blood, off-targeting features, and inadequate tumor site accumulation; new delivery mechanisms are needed to address these issues. A polysaccharide made from chitin, chitosan has found extensive use in the creation of nanoparticles. The delivery of genes in the treatment of illnesses, particularly cancer, has made use of nanostructures modified with chitosan. Topics covered in this review center on cancer treatment using chitosan-based polymers for siRNA delivery. This study aims to assess the potential of chitosan nanoparticles for the simultaneous administration of siRNA and anti-cancer medications. In cancer treatment, these nanoparticles can transport phytochemicals or chemotherapeutics together with siRNA. In addition, chitosan nanoparticles loaded with siRNA can inhibit the growth and spread of human malignancies by delivering siRNA that targets particular genes. Chitosan nanoparticles loaded with siRNA can heighten the responsiveness of cancer cells. Future therapeutic applications of chitosan nanoparticles may open the path for cancer treatment, thanks to their biocompatibility and biosafety.

Pharmaceutical chitosan hydrogels: A review on its design and applications

Chitosan (CS) has become a focal point of extensive research in the pharmaceutical industry due to its remarkable biodegradability, biocompatibility and sustainability. Chitosan hydrogels (CS HGs) are characterized by their viscoelasticity, flexibility and softness. The polar surfaces exhibit properties that mitigate interfacial tension between the hydrogel and body fluids. The inherent compatibility of CS HGs with body tissues and fluids positions them as outstanding polymers for delivering therapeutic proteins, peptides, DNA, siRNA, and vaccines. Designed to release drugs through mechanisms such as swelling-based diffusion, bioerosion, and responsiveness to stimuli, CS HGs offer a versatile platform for drug delivery. CS HGs play pivotal roles in serving purposes such as prolonging the duration of preprogrammed drug delivery, enabling stimuli-responsive smart delivery to target sites, protecting encapsulated drugs within the mesh network from adverse environments, and facilitating mucoadhesion and penetration through cell membranes. This review comprehensively outlines various novel preparation methods of CS HGs, delving into the parameters influencing drug delivery system design, providing a rationale for CS HG utilization in drug delivery, and presenting diverse applications across the pharmaceutical landscape. In synthesizing these facets, the review seeks to contribute to a nuanced understanding of the multifaceted role that CS HGs play in advancing drug delivery methodologies.

A review on the encapsulation of "eco-friendly" compounds in natural polymer-based nanoparticles as next generation nano-agrochemicals for sustainable agriculture and crop management

Crop management techniques and sustainable agriculture offer a comprehensive farming method that incorporates social, economic, and ecological factors. Sustainable agriculture places a high priority on soil health, water efficiency, and biodiversity conservation in order to develop resilient and regenerative food systems that can feed both the current and future generations. Our goal in this review is to give a thorough overview of current developments in the use of polysaccharides as raw materials for the encapsulation of natural chemicals in nanoparticles as novel crop protection products. The search for recent research articles and latest reviews has been carried out through pubmed, google scholar, BASE as search engines. Offer cutting-edge solutions for sustainable crop management that satisfy the demands of an expanding population, comply with changing legal frameworks, and address environmental issues by encasing natural compounds inside polysaccharide-based nanoparticles. A variety of natural substances, such as essential oils, plant extracts, antimicrobials compounds and miRNA, can be included in these nanoparticles. These materials have many advantages, such as biocompatibility, biodegradability and controlled release of active compounds. Thanks to their action mechanism, they are able to mediate hormone signaling and gene expression in different plant physiological aspects, as well as enhance their tolerance to abiotic stress conditions. Sustainable agriculture can be supported by this type of treatments, correctly developing food safety through the production of non-toxic nanoparticles, low-cost industrial scale-up and the use of biodegradable materials. Polysaccharide-based nanoparticles have a wide range of uses in agriculture: they improve crop yields, encourage "eco-friendly" farming methods and can decrease the concentrations of active ingredient used, providing an accurate and affective dosage without damaging further species, as well as avoiding treatment resistance risks. These nanoparticles can also reduce the negative effects of chemical fertilizers and pesticides, contributing to the environmentally friendly agricultural development. Furthermore, the application of polysaccharide-based nanoparticles is consistent with the expanding trend of green and sustainable agriculture.

Polymers as Efficient Non-Viral Gene Delivery Vectors: The Role of the Chemical and Physical Architecture of Macromolecules

Gene therapy is the technique of inserting foreign genetic elements into host cells to achieve a therapeutic effect. Although gene therapy was initially formulated as a potential remedy for specific genetic problems, it currently offers solutions for many diseases with varying inheritance patterns and acquired diseases. There are two major groups of vectors for gene therapy: viral vector gene therapy and non-viral vector gene therapy. This review examines the role of a macromolecule's chemical and physical architecture in non-viral gene delivery, including their design and synthesis. Polymers can boost circulation, improve delivery, and control cargo release through various methods. The prominent examples discussed include poly-L-lysine, polyethyleneimine, comb polymers, brush polymers, and star polymers, as well as hydrogels and natural polymers and their modifications. While significant progress has been made, challenges still exist in gene stabilization, targeting specificity, and cellular uptake. Overcoming cytotoxicity, improving delivery efficiency, and utilizing natural polymers and hybrid systems are vital factors for prospects. This comprehensive review provides an illuminating overview of the field, guiding the way toward innovative non-viral-based gene delivery solutions.

Functionalized hydrogels as smart gene delivery systems to treat musculoskeletal disorders

Despite critical advances in regenerative medicine, the generation of definitive, reliable treatments for musculoskeletal diseases remains challenging. Gene therapy based on the delivery of therapeutic genetic sequences has strong value to offer effective, durable options to decisively manage such disorders. Furthermore, scaffold-mediated gene therapy provides powerful alternatives to overcome hurdles associated with classical gene therapy, allowing for the spatiotemporal delivery of candidate genes to sites of injury. Among the many scaffolds for musculoskeletal research, hydrogels raised increasing attention in addition to other potent systems (solid, hybrid scaffolds) due to their versatility and competence as drug and cell carriers in tissue engineering and wound dressing. Attractive functionalities of hydrogels for musculoskeletal therapy include their injectability, stimuli-responsiveness, self-healing, and nanocomposition that may further allow to upgrade of them as "intelligently" efficient and mechanically strong platforms, rather than as just inert vehicles. Such functionalized hydrogels may also be tuned to successfully transfer therapeutic genes in a minimally invasive manner in order to protect their cargos and allow for their long-term effects. In light of such features, this review focuses on functionalized hydrogels and demonstrates their competence for the treatment of musculoskeletal disorders using gene therapy procedures, from gene therapy principles to hydrogel functionalization methods and applications of hydrogel-mediated gene therapy for musculoskeletal disorders, while remaining challenges are being discussed in the perspective of translation in patients. STATEMENT OF SIGNIFICANCE: Despite advances in regenerative medicine, the generation of definitive, reliable treatments for musculoskeletal diseases remains challenging. Gene therapy has strong value in offering effective, durable options to decisively manage such disorders. Scaffold-mediated gene therapy provides powerful alternatives to overcome hurdles associated with classical gene therapy. Among many scaffolds for musculoskeletal research, hydrogels raised increasing attention. Functionalities including injectability, stimuli-responsiveness, and self-healing, tune them as "intelligently" efficient and mechanically strong platforms, rather than as just inert vehicles. This review introduces functionalized hydrogels for musculoskeletal disorder treatment using gene therapy procedures, from gene therapy principles to functionalized hydrogels and applications of hydrogel-mediated gene therapy for musculoskeletal disorders, while remaining challenges are discussed from the perspective of translation in patients.

Trends in sustainable chitosan-based hydrogel technology for circular biomedical engineering: A review

Eco-friendly materials have emerged in biomedical engineering, driving major advances in chitosan-based hydrogels. These hydrogels offer a promising green alternative to conventional polymers due to their non-toxicity, biodegradability, biocompatibility, environmental friendliness, affordability, and easy accessibility. Known for their remarkable properties such as drug encapsulation, delivery capabilities, biosensing, functional scaffolding, and antimicrobial behavior, chitosan hydrogels are at the forefront of biomedical research. This paper explores the fabrication and modification methods of chitosan hydrogels for diverse applications, highlighting their role in advancing climate-neutral healthcare technologies. It reviews significant scientific advancements and trends chitosan hydrogels focusing on cancer diagnosis, drug delivery, and wound care. Additionally, it addresses current challenges and green synthesis practices that support a circular economy, enhancing biomedical sustainability. By providing an in-depth analysis of the latest evidence on climate-neutral management, this review aims to facilitate informed decision-making and foster the development of sustainable strategies leveraging chitosan hydrogel technology. The insights from this comprehensive examination are pivotal for steering future research and applications in sustainable biomedical solutions.

The menace of severe adverse events and deaths associated with viral gene therapy and its potential solution

Over the past decade, in vivo gene replacement therapy has significantly advanced, resulting in market approval of numerous therapeutics predominantly relying on adeno-associated viral vectors (AAV). While viral vectors have undeniably addressed several critical healthcare challenges, their clinical application has unveiled a range of limitations and safety concerns. This review highlights the emerging challenges in the field of gene therapy. At first, we discuss both the role of biological barriers in viral gene therapy with a focus on AAVs, and review current landscape of in vivo human gene therapy. We delineate advantages and disadvantages of AAVs as gene delivery vehicles, mostly from the safety perspective (hepatotoxicity, cardiotoxicity, neurotoxicity, inflammatory responses etc.), and outline the mechanisms of adverse events in response to AAV. Contribution of every aspect of AAV vectors (genomic structure, capsid proteins) and host responses to injected AAV is considered and substantiated by basic, translational and clinical studies. The updated evaluation of recent AAV clinical trials and current medical experience clearly shows the risks of AAVs that sometimes overshadow the hopes for curing a hereditary disease. At last, a set of established and new molecular and nanotechnology tools and approaches are provided as potential solutions for mitigating or eliminating side effects. The increasing number of severe adverse reactions and, sadly deaths, demands decisive actions to resolve the issue of immune responses and extremely high doses of viral vectors used for gene therapy. In response to these challenges, various strategies are under development, including approaches aimed at augmenting characteristics of viral vectors and others focused on creating secure and efficacious non-viral vectors. This comprehensive review offers an overarching perspective on the present state of gene therapy utilizing both viral and non-viral vectors.

Advanced gene therapy system for the treatment of solid tumour: A review

In contrast to conventional therapies that require repeated dosing, gene therapy can treat diseases by correcting defective genes after a single transfection and achieving cascade amplification, and has been widely studied in clinical settings. However, nucleic acid drugs are prone to catabolism and inactivation. A variety of nucleic acid drug vectors have been developed to protect the target gene against nuclease degradation and increase the transformation efficiency and safety of gene therapy. In addition, gene therapy is often combined with chemotherapy, phototherapy, magnetic therapy, ultrasound, and other therapeutic modalities to improve the therapeutic effect. This review systematically introduces ribonucleic acid (RNA) interference technology, antisense oligonucleotides, and clustered regularly interspaced short palindromic repeat/CRISPR-associated nuclease 9 (CRISPR/Cas9) genome editing. It also introduces the commonly used nucleic acid drug vectors, including viral vectors (adenovirus, retrovirus, etc.), organic vectors (lipids, polymers, etc.), and inorganic vectors (MOFs, carbon nanotubes, mesoporous silica, etc.). Then, we describe the combined gene therapy modalities and the pathways of action and report the recent applications in solid tumors of the combined gene therapy. Finally, the challenges of gene therapy in solid tumor treatment are introduced, and the prospect of application in this field is presented.

The anti-cancer properties of miR-340 plasmid-chitosan complexes (miR-340 CC) on murine model of breast cancer

MiRNA-340 (miR-340) has been found to have tumour-suppressing effects in breast cancer (BC). However, for clinical use, miRNAs need to be delivered safely and effectively to protect them from degradation. In our previous study, we used chitosan complexes as a safe carrier with anti-cancer properties to deliver miR-340 plasmid into 4T1 cells. This study explored further information concerning the anti-cancer impacts of both chitosan and miR-340 plasmid in a murine model of BC. Mice bearing 4T1 cells were intra-tumorally administered miR-340 plasmid-chitosan complexes (miR-340 CC). Afterwards, the potential of miR-340 CC in promoting anti-tumour immune responses was evaluated. MiR-340 CC significantly reduced tumour size, inhibited metastasis, and prolonged the survival of mice. MiR-340 CC up-regulates P-27 gene expression related to cancer cell apoptosis, and down-regulates gene expressions involved in angiogenesis and metastasis (breast regression protein-39 (BRP-39)) and CD163 as an anti-inflammatory macrophages (MQs) marker. Furthermore, CD47 expression as a MQs immune check-point was remarkably decreased after miR-340 CC treatment. The level of IL-12 in splenocytes of miR-340 CC treated mice increased, while the level of IL-10 decreased, indicating anti-cancer immune responses. Our findings display that miR-340 CC can be considered as a promising therapy in BC.

Separation and purification of hyaluronic acid by Fe3O4 nano and micro particles coated with chitosan and silica

Hyaluronic acid (HA), a glycosaminoglycan, is comprised of alternating units of D-glucuronic acid and N-acetylglucosamine. This compound harbors numerous biomedical applications, including its use in pharmaceuticals, wound healing, osteoarthritis treatment, and drug delivery. Its unique composition and exceptional features, such as its high water-absorbing and retaining capacity, have also led to its use in the cosmetics industry. The employment of this biopolymer has given rise to an escalation in the request for its manufacture. The present investigation has explored the correlation between hyaluronic acid and chitosan and silica for the purpose of separation. Consequently, Iron oxide magnetic nano particles and micro particles were produced via co-precipitation method and were layered with chitosan and silica to purify the hyaluronic acid from the fermentation broth that was generated by Streptococcus Zooepidemicus. The size distribution and zeta potentials of the two kinds of particles were gauged with the aid of a dynamic laser light scattering apparatus and zeta potential meter (Malvern, Zeta master) respectively. The confirmation of the chemical structure of the Fe3O4 nanoparticles and Fe3O4 particles conjugated with chitosan and silica was accomplished through the utilization of Fourier Transform Infrared Spectroscopy (FT-IR). Protein contamination was thoroughly characterized by means of sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Nanodrop 2000/2000c spectrophotometers protein estimation method. The maximum HA adsorption capacity, under optimal pH conditions of 4, was determined to be 87 mg/g, 112 mg/g, 51 mg/g, and 44 mg/g for Fe3O4 -chitosan nanoparticle, Fe3O4 -chitosan micro particle, Fe3O4 -silica microparticle, and Fe3O4 -silica nanoparticle, respectively.

Stimulus-Responsive Nanodelivery and Release Systems for Cancer Gene Therapy: Efficacy Improvement Strategies

Introduction of exogenous genes into target cells to overcome various tumor diseases caused by genetic defects or abnormalities and gene therapy, a new treatment method, provides a promising strategy for tumor treatment. Over the past decade, gene therapy has made exciting progress; however, it still faces the challenge of low nucleic acid delivery and release efficiencies. The emergence of nonviral vectors, primarily nanodelivery and release systems (NDRS), has resulted in a historic breakthrough in the application of gene therapy. NDRS, especially stimulus-responsive NDRS that can respond in a timely manner to changes in the internal and external microenvironment (eg, low pH, high concentration of glutathione/reactive oxygen species, overexpressed enzymes, temperature, light, ultrasound, and magnetic field), has shown excellent loading and release advantages in the precision and efficiency of tumor gene therapy and has been widely applied. The only disadvantage is that poor transfection efficiency limits the in-depth application of gene therapy in clinical practice, owing to the presence of biological barriers in the body. Therefore, this review first introduces the development history of gene therapy, the current obstacles faced by gene delivery, strategies to overcome these obstacles, and conventional vectors, and then focuses on the latest research progress in various stimulus-responsive NDRS for improving gene delivery efficiency. Finally, the future challenges and prospects that stimulus-responsive NDRS may face in clinical application and transformation are discussed to provide references for enhancing in-depth research on tumor gene therapy.

Gene Therapy with Chitosan Nanoparticles: Modern Formulation Strategies for Enhancing Cancer Cell Transfection

Gene therapy involves the introduction of exogenous genetic material into host tissues to modify gene expression or cellular properties for therapeutic purposes. Initially developed to address genetic disorders, gene therapy has expanded to encompass a wide range of conditions, notably cancer. Effective delivery of nucleic acids into target cells relies on carriers, with non-viral systems gaining prominence due to their enhanced safety profile compared to viral vectors. Chitosan, a biopolymer, is frequently utilized to fabricate nanoparticles for various biomedical applications, particularly nucleic acid delivery, with recent emphasis on targeting cancer cells. Chitosan's positively charged amino groups enable the formation of stable nanocomplexes with nucleic acids and facilitate interaction with cell membranes, thereby promoting cellular uptake. Despite these advantages, chitosan-based nanoparticles face challenges such as poor solubility at physiological pH, non-specificity for cancer cells, and inefficient endosomal escape, limiting their transfection efficiency. To address these limitations, researchers have focused on enhancing the functionality of chitosan nanoparticles. Strategies include improving stability, enhancing targeting specificity, increasing cellular uptake efficiency, and promoting endosomal escape. This review critically evaluates recent formulation approaches within these categories, aiming to provide insights into advancing chitosan-based gene delivery systems for improved efficacy, particularly in cancer therapy.

Comparison of two methods of sperm- and testis-mediated gene transfer in production of transgenic animals: A systematic review

Transgenic (Tg) animal technology is one of the growing areas in biology. Various Tg technologies, each with its own advantages and disadvantages, are available for generating Tg animals. These include zygote microinjection, electroporation, viral infection, embryonic stem cell or spermatogonial stem cell-mediated production of Tg animals, sperm-mediated gene transfer (SMGT), and testis-mediated gene transfer (TMGT). However, there are currently no comprehensive studies comparing SMGT and TMGT methods, selecting appropriate gene delivery carriers (such as nanoparticles and liposomes), and determining the optimal route for gene delivery (SMGT and TMGT) for producing Tg animal. Here we aim to provide a comprehensive assessment comparing SMGT and TMGT methods, and to introduce the best carriers and gene transfer methods to sperm and testis to generate Tg animals in different species. From 2010 to 2022, 47 studies on SMGT and 25 studies on TMGT have been conducted. Mice and rats were the most commonly used species in SMGT and TMGT. Regarding the SMGT approach, nanoparticles, streptolysin-O, and virus packaging were found to be the best gene transfer methods for generating Tg mice. In the TMGT method, the best gene transfer methods for generating Tg mice and rats were virus packaging, dimethyl sulfoxide, electroporation, and liposome. Our study has shown that the efficiency of producing Tg animals varies depending on the species, gene carrier, and method of gene transfer.

Nanomaterial-encapsulated dsRNA of ecdysone-induced early gene E75, a potential RNAi-based SIT strategy for pest control against Bactrocera dorsalis

Bactrocera dorsalis is a notorious pest widely distributed across most Asian countries. With the rapid development of pesticide resistance, new pest control methods are urgently needed. RNAi-based sterile insect technique (SIT) is a species-specific pest management strategy for B. dorsalis control. It is of great significance to identify more target genes from B. dorsalis, and improve the RNAi efficiency. In this study, microinjection-based RNAi results showed that six 20E response genes were necessary for male fertility of B. dorsalis, of which E75 was identified as the key target according to the lowest egg-laying number and hatching rate after E75 knockdown. Three nanoparticles chitosan (CS), chitosan‑sodium tripolyphosphate (CS-TPP), and star polycation (SPc) were used to encapsulate dsE75 expressed by HT115 strain. Properties analysis of nanoparticle-dsRNA complexes showed that both CS-TPP-dsRNA and SPc-dsRNA exhibited better properties (smaller size and polydispersity index) than CS-dsRNA. Moreover, oral administration of CS-TPP-dsE75 and SPc-dsE75 by males resulted in more abnormal testis and significantly lower fertility than feeding naked dsE75. Semi-field trials further confirmed that the number of hatched larvae was dramatically reduced in these two groups. Our study not only provides more valuable targets for RNAi-based SIT, but also promotes the application of environment-friendly management against B. dorsalis in the field.

Novel polyurethane-based ionene nanoparticles electrostatically stabilized with hyaluronic acid for effective gene therapy

Gene therapy is considered to be a valuable strategy for effective cancer treatment. However, the development of effective delivery systems that can specifically deliver gene materials, such as siRNA to tumor tissues plays a critical role in cancer therapy. In the present study, we have developed a novel complex that is based on an electrostatic interaction between cationic polyurethane ionene (CPUI) nanoparticles and an anti-signal transducer and activator of transcription 3 (STAT3) siRNA. For active targeting, hyaluronic acid (HA) was used to coat the complexes, which significantly reduced the cytotoxicity of the blank nanocarriers while demonstrating high transport efficiency of the siRNA via the CD44-mediated endocytosis pathway in MCF-7 breast cancer cells. The targeted nanocarriers (HA/CPUI/siRNA) showed significantly higher cellular internalization in flow cytometry and confocal microscopy compared with the non-targeted system (CPUI/siRNA). In addition, the incorporation of HA on the surface of the complexes resulted in significantly greater suppression of the STAT3 gene compared to the corresponding non-targeted formulation. Whole-body fluorescence images showed more significant tumor accumulation of the targeted nanocarriers in 4T1 breast tumor-bearing mice. Therefore, HA/CPUI/siRNA nanocarriers are an interesting option for the siRNA-targeted treatment of breast cancer cells.

Nanotechnology strategies to address challenges in topical and cellular delivery of siRNAs in skin disease therapy

Gene therapy is one of the most advanced therapies in current medicine. In particular, interference RNA-based therapy by small interfering RNA (siRNA) has gained attention in recent years as it is a highly versatile, selective and specific therapy. In dermatological conditions, topical delivery of siRNA offers numerous therapeutic advantages, mainly by inhibiting the expression of target transcripts directly in the skin. However, crossing the stratum corneum and overcoming intracellular barriers is an inherent challenge. Substantial efforts by scientists have moved towards the use of multimodal and multifunctional nanoparticles to overcome these barriers and achieve greater bioavailability in their site of action, the cytoplasm. In this review the most innovative strategies based on nanoparticle and physical methods are presented, as well as the design principles and the main factors that contribute to the performance of these systems. This review also highlights the synergistic contributions of medicine, nanotechnology, and molecular biology to advancing translational research into siRNA-based therapeutics for skin diseases.

Nanogels: Smart tools to enlarge the therapeutic window of gene therapy

Gene therapy can potentially treat a great number of diseases, from cancer to rare genetic disorders. Very recently, the development and emergency approval of nucleic acid-based COVID-19 vaccines confirmed its strength and versatility. However, gene therapy encounters limitations due to the lack of suitable carriers to vectorize therapeutic genetic material inside target cells. Nanogels are highly hydrated nano-size crosslinked polymeric networks that have been used in many biomedical applications, from drug delivery to tissue engineering and diagnostics. Due to their easy production, tunability, and swelling properties they have called the attention as promising vectors for gene delivery. In this review, nanogels are discussed as vectors for nucleic acid delivery aiming to enlarge gene therapy's therapeutic window. Recent works highlighting the optimization of inherent transfection efficiency and biocompatibility are reviewed here. The importance of the monomer choice, along with the internal structure, surface decoration, and responsive features are outlined for the different transfection modalities. The possible sources of toxicological endpoints in nanogels are analyzed, and the strategies to limit them are compared. Finally, perspectives are discussed to identify the remining challenges for the nanogels before their translation to the market as transfection agents.

Exploring modified chitosan-based gene delivery technologies for therapeutic advancements

One of the critical steps in gene therapy is the successful delivery of the genes. Immunogenicity and toxicity are major issues for viral gene delivery systems. Thus, non-viral vectors are explored. A cationic polysaccharide like chitosan could be used as a nonviral gene delivery vector owing to its significant interaction with negatively charged nucleic acid and biomembrane, providing effective cellular uptake. However, the native chitosan has issues of targetability, unpacking ability, and solubility along with poor buffer capability, hence requiring modifications for effective use in gene delivery. Modified chitosan has shown that the "proton sponge effect" involved in buffering the endosomal pH results in osmotic swelling owing to the accumulation of a greater amount of proton and chloride along with water. The major challenges include limited exploration of chitosan as a gene carrier, the availability of high-purity chitosan for toxicity reduction, and its immunogenicity. The genetic drugs are in their infancy phase and require further exploration for effective delivery of nucleic acid molecules as FDA-approved marketed formulations soon.

Modeling and characterization of lenalidomide-loaded tripolyphosphate-crosslinked chitosan nanoparticles for anticancer drug delivery

Tripolyphosphate-crosslinked chitosan (TPPCS) nanoparticles were employed in the encapsulation of lenalidomide (LND) using a straightforward ionic cross-linking approach. The primary objectives of this technique were to enhance the bioavailability of LND and mitigate inadequate or overloading of hydrophobic and sparingly soluble drug towards cancer cells. In this context, a quantum chemical model was employed to elucidate the characteristics of TPPCS nanoparticles, aiming to assess the efficiency of these nanocarriers for the anticancer drug LND. Fifteen configurations of TPPCS and LND (TPPCS /LND1-15) were optimized using B3LYP density functional level of theory and PCM model (H2O). AIM analysis revealed that the high drug loading capacity of TPPCS can be attributed to hydrogen bonds, as supported by the average binding energy (168 kJ mol-1). The encouraging theoretical results prompted us to fabricate this drug delivery system and characterize it using advanced analytical techniques. The encapsulation efficiency of LND within the TPPCS was remarkably high, reaching approximately 87 %. Cytotoxicity studies showed that TPPCS/LND nanoparticles are more effective than the LND drug. To sum up, TPPCS/LND nanoparticles improved bioavailability of poorly soluble LND through cancerous cell membrane. In light of this accomplishment, the novel drug delivery route enhances efficiency, allowing for lower therapy doses.

Anti-cancer Effects of a Chitosan Based Nanoformulation Expressing miR-340 on 4T1 Breast Cancer Cells

MicroRNAs (miRNAs) have a crucial role in the regulation of gene expression in tumor development, invasion, and metastasis. Herein, miRNA-340 (miR-340) has been shown to play tumor suppressor activity in breast cancer (BC). However, the clinical applications of miRNAs request the development of safe and effective delivery systems capable of protecting nucleic acids from degradation. In this study, biodegradable chitosan nanoparticles incorporating miR-340 plasmid DNA (pDNA) (miR-340 CNPs) were synthesized and characterized. Then, the anti-tumor effects of miR-340 CNPs were investigated using 4T1 BCE cells. The spherical nanoparticles (NPs) with an appropriate mean diameter of around 266 ± 9.3 nm and zeta potential of +17 ± 1.8 mV were successfully prepared. The NPs showed good stability, high entrapment efficiency and a reasonable release behavior, meanwhile their high resistance against enzymatic degradation was verified. Furthermore, NPs demonstrated appropriate transfection efficiency and could induce apoptosis, so had toxicity in 4T1 BCE cells. Also, CD47 expression on the surface of cancer cells was significantly reduced after treatment with miR-340 CNPs. The results showed that miR-340 CNPs augmented the expression of P-27 in BC cells. Furthermore, miR-340 CNPs caused down-regulation of BRP-39 (breast regression protein-39) increasingly suggested as a prognostic biomarker for neoplastic diseases like BC. In conclusion, our data show that miR-340 CNPs can be considered as a promising new platform for BC gene therapy.

Chitosan-Functionalized Poly(β-Amino Ester) Hybrid System for Gene Delivery in Vaginal Mucosal Epithelial Cells

Gene therapy displays great promise in the treatment of cervical cancer. The occurrence of cervical cancer is highly related to persistent human papilloma virus (HPV) infection. The HPV oncogene can be cleaved via gene editing technology to eliminate carcinogenic elements. However, the successful application of the gene therapy method depends on effective gene delivery into the vagina. To improve mucosal penetration and adhesion ability, quaternized chitosan was introduced into the poly(β-amino ester) (PBAE) gene-delivery system in the form of quaternized chitosan-g-PBAE (QCP). At a mass ratio of PBAE:QCP of 2:1, the polymers exhibited the highest green fluorescent protein (GFP) transfection efficiency in HEK293T and ME180 cells, which was 1.1 and 5.4 times higher than that of PEI 25 kD. At this mass ratio, PBAE-QCP effectively compressed the GFP into spherical polyplex nanoparticles (PQ-GFP NPs) with a diameter of 255.5 nm. In vivo results indicated that owing to the mucopenetration and adhesion capability of quaternized CS, the GFP transfection efficiency of the PBAE-QCP hybrid system was considerably higher than those of PBAE and PEI 25 kD in the vaginal epithelial cells of Sprague-Dawley rats. Furthermore, the new system demonstrated low toxicity and good safety, laying an effective foundation for its further application in gene therapy.

Constructing Nucleic Acid Delivering Lipoproteoplexes from Coiled-Coil Supercharged Protein and Cationic Liposomes

The safe and efficient delivery of nucleic acids is crucial for both clinical applications of gene therapy and pre-clinical laboratory research. Such delivery strategies rely on vectors to condense nucleic acid payloads and escort them into the cell without being degraded in the extracellular environment; however, the construction and utilization of these vectors can be difficult and time-consuming. Here, we detail the steps involved in the rapid, laboratory-scale production and assessment of a versatile, nucleic acid delivery vehicle, known as the lipoproteoplex. In this chapter, we outline: (1) the recombinant synthesis and subsequent purification of the supercharged coiled-coil protein component known as N8; (2) the synthesis of cationic liposomes from dioleoyl-3-trimethylammonium propane (DOTAP) and sodium cholate; (3) and finally a protocol for the delivery of a model siRNA cargo into a cultured cell line.

Multiple Natural Polymers in Drug and Gene Delivery Systems

Natural polymers are organic compounds produced by living organisms. In nature, they exist in three main forms, including proteins, polysaccharides, and nucleic acids. In recent years, with the continuous research on drug and gene delivery systems, scholars have found that natural polymers have promising applications in drug and gene delivery systems due to their excellent properties such as biocompatibility, biodegradability, low immunogenicity, and easy modification. However, since the structure, physicochemical properties, pharmacological properties and biological characteristics of biopolymer molecules have not yet been entirely understood, further studies are required before large-scale clinical application. This review focuses on recent advances in the representative natural polymers such as proteins (albumin, collagen, elastin), polysaccharides (chitosan, alginate, cellulose) and nucleic acids. We introduce the characteristics of various types of natural polymers, and further outline the characterization methods and delivery forms of these natural polymers. Finally, we discuss possible challenges for natural polymers in subsequent experimental studies and clinical applications. It provides an important strategy for the clinical application of natural polymers in drug and gene delivery systems.

N-lauric-O-carboxymethyl chitosan: Synthesis, characterization and application as a pH-responsive carrier for curcumin particles

A pH-responsive amphiphilic chitosan derivative, N-lauric-O-carboxymethyl chitosan (LA-CMCh), is synthesized. Its molecular structures are characterized by FTIR, 1H NMR, and XRD methods. The influencing factors are investigated, including the amount of lauric acid (LA), carboxymethyl chitosan (CMCh), N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC), and N-hydroxysuccinimide (NHS), and their molar ratio, reaction time, and reaction temperature on the substitution. The degrees of substitution (DS) of the lauric groups on the -NH2 groups are calculated based on the integrated data of 1H NMR spectra. The optimum reaction condition is obtained as a reaction time of 6 h, a reaction temperature of 80 °C, and a molar ratio of lauric acid to O-carboxymethyl chitosan to N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride to N-hydroxysuccinimide of 1:3:4.5:4.5, respectively. The crystallinity and initial decomposition temperature of LA-CMCh decrease, but the maximum decomposition temperature increases. The crystallinity is reduced due to the introduction of LA and the degree of hydrogen bonding among LA-CMCh molecules. LA-CMCh could self-aggregate into particles, which size and critical aggregation concentration depend on the degree of substitution and medium pH. LA-CMCh aggregates could load curcumin up to 21.70 %, and continuously release curcumin for >200 min. LA-CMCh shows nontoxicity to fibroblast HFF-1 cells and good antibacterial activity against S. aureus and E. coli, indicating that it could be used as an oil-soluble-drug carrier.

Optimized DOX Drug Deliveries via Chitosan-Mediated Nanoparticles and Stimuli Responses in Cancer Chemotherapy: A Review

Chitosan nanoparticles (NPs) serve as useful multidrug delivery carriers in cancer chemotherapy. Chitosan has considerable potential in drug delivery systems (DDSs) for targeting tumor cells. Doxorubicin (DOX) has limited application due to its resistance and lack of specificity. Chitosan NPs have been used for DOX delivery because of their biocompatibility, biodegradability, drug encapsulation efficiency, and target specificity. In this review, various types of chitosan derivatives are discussed in DDSs to enhance the effectiveness of cancer treatments. Modified chitosan-DOX NP drug deliveries with other compounds also increase the penetration and efficiency of DOX against tumor cells. We also highlight the endogenous stimuli (pH, redox, enzyme) and exogenous stimuli (light, magnetic, ultrasound), and their positive effect on DOX drug delivery via chitosan NPs. Our study sheds light on the importance of chitosan NPs for DOX drug delivery in cancer treatment and may inspire the development of more effective approaches for cancer chemotherapy.

Nanobiotechnology-based strategies in alleviation of chemotherapy-mediated cardiotoxicity

The cardiovascular diseases have been among the most common malignancies and the first leading cause of death, even higher than cancer. The cardiovascular diseases can be developed as a result of cardiac dysfunction and damages to heart tissue. Exposure to toxic agents and chemicals that induce cardiac dysfunction has been of interest in recent years. The chemotherapy drugs are commonly used for cancer therapy and in these patients, cardiovascular diseases have been widely observed that is due to negative impact of chemotherapy drugs on the heart. These drugs increase oxidative damage and inflammation, and mediate apoptosis and cardiac dysfunction. Hence, nanotechnological approaches have been emerged as new strategies in attenuation of chemotherapy-mediated cardiotoxicity. The first advantage of nanoparticles can be explored in targeted and selective delivery of drugs to reduce their accumulation in heart tissue. Nanostructures can deliver bioactive and therapeutic compounds in reducing cardiotoxicity and alleviation toxic impacts of chemotherapy drugs. The functionalization of nanostructures increases their selectivity against tumor cells and reduces accumulation of drugs in heart tissue. The bioplatforms such as chitosan and alginate nanostructures can also deliver chemotherapy drugs and reduce their cardiotoxicity. The function of nanostructures is versatile in reduction of cardiotoxicity by chemotherapy drugs and new kind of platforms is hydrogels that can mediate sustained release of drug to reduce its toxic impacts on heart tissue. The various kinds of nanoplatforms have been developed for alleviation of cardiotoxicity and their future clinical application depends on their biocompatibility. High concentration level of chitosan nanoparticles can stimulate cardiotoxicity. Therefore, if nanotechnology is going to be deployed for drug delivery and reducing cardiotoxicity, the first pre-requirement is to lack toxicity on normal cells and have high biocompatibility.

Advances in preparation, biomedical, and pharmaceutical applications of chitosan-based gold, silver, and magnetic nanoparticles: A review

During the last decades, the ever-increasing incidence of various diseases, like cancer, has led to a high rate of death worldwide. On the other hand, conventional modalities (such as chemotherapy and radiotherapy) have not indicated enough efficiency in the diagnosis and treatment of diseases. Thus, potential novel approaches should be taken into consideration to pave the way for the suppression of diseases. Among novel approaches, biomaterials, like chitosan nanoparticles (CS NPs, N-acetyl-glucosamine and D-glucosamine), have been approved by the FDA for some efficient pharmaceutical applications. These NPs owing to their physicochemical properties, modification with different molecules, biocompatibility, serum stability, less immune response, suitable pharmacokinetics and pharmacodynamics, etc. have received deep attention among researchers and clinicians. More importantly, the impact of CS polysaccharide in the synthesis, preparation, and delivery of metallic NPs (like gold, silver, and magnetic NPs), and combination of CS with these metallic NPs can further facilitate the diagnosis and treatment of diseases. Metallic NPs possess some features, like converting NIR photon energy into thermal energy and anti-microorganism capability, and can be a potential candidate for the diagnosis and treatment of diseases in combination with CS NPs. These combined NPs would be efficient pharmaceuticals in the future.

Chitosan-Based Sustained Expression of Sterol Regulatory Element-Binding Protein 1a Stimulates Hepatic Glucose Oxidation and Growth in Sparus aurata

The administration of a single dose of chitosan nanoparticles driving the expression of sterol regulatory element-binding protein 1a (SREBP1a) was recently associated with the enhanced conversion of carbohydrates into lipids. To address the effects of the long-lasting expression of SREBP1a on the growth and liver intermediary metabolism of carnivorous fish, chitosan-tripolyphosphate (TPP) nanoparticles complexed with a plasmid expressing the N terminal active domain of hamster SREBP1a (pSG5-SREBP1a) were injected intraperitoneally every 4 weeks (three doses in total) to gilthead sea bream (Sparus aurata) fed high-protein-low-carbohydrate and low-protein-high-carbohydrate diets. Following 70 days of treatment, chitosan-TPP-pSG5-SREBP1a nanoparticles led to the sustained upregulation of SREBP1a in the liver of S. aurata. Independently of the diet, SREBP1a overexpression significantly increased their weight gain, specific growth rate, and protein efficiency ratio but decreased their feed conversion ratio. In agreement with an improved conversion of dietary carbohydrates into lipids, SREBP1a expression increased serum triglycerides and cholesterol as well as hepatic glucose oxidation via glycolysis and the pentose phosphate pathway, while not affecting gluconeogenesis and transamination. Our findings support that the periodical administration of chitosan-TPP-DNA nanoparticles to overexpress SREBP1a in the liver enhanced the growth performance of S. aurata through a mechanism that enabled protein sparing by enhancing dietary carbohydrate metabolisation.

A water-soluble and biocompatible chitosan-based fluorescent probe for real-time monitoring formaldehyde in living cells and zebrafish

Formaldehyde (HCHO) is a common environmental toxicant that can harm the human respiratory tract and nervous system when exposed for long period of time. As a carcinogen, HCHO also increases the risk of cancer in humans. HCHO can be produced endogenously in living systems and plays an essential role in physiological and biochemical reactions and pathogenesis. Therefore, monitoring the level of HCHO in vivo and in vitro has become the focus of attention. The designed naphthalene fluorophore was introduced onto modified chitosan to prepare a chitosan-based fluorescent probe (CS-FA) for HCHO detection. Compared to other small-molecule probe analogs for the detection of HCHO, the randomly coiled polymer chain of chitosan enabled CS-FA to "enrich" HCHO using the synergistic binding of hydrazino-naphthalimide recognition sites. Thus, the reaction of the analyte with the recognition site was accelerated, resulting in a faster equilibrium fluorescence response (2-3 min) and high sensitivity. In addition, the introduction of biomass material chitosan also improved the biocompatibility of the probe. Then a series of composite materials (test strips and hydrogel) were prepared based on the probe to expand the application form of the probe.

Lipid-Polymer Hybrid Nanoparticles with Both PD-L1 Knockdown and Mild Photothermal Effect for Tumor Photothermal Immunotherapy

In developing countries, the incidence of colorectal cancer (CRC) is on the rise. The combination of programmed cell death ligand-1 (PD-L1) siRNA (siPD-L1) and mild photothermal therapy (PTT) is a promising strategy for CRC treatment. In this study, dopamine-modified polyethylenimine (PEI) was prepared to fabricate an IR780 and siPD-L1 codelivery lipid-polymer hybrid nanoparticle (lip@PSD-siP) for the photothermal immunotherapy of CRC. The modification of dopamine can significantly reduce the cytotoxicity of PEI. lip@PSD-siP can be effectively taken up by CT26 cells and successfully escaped from lysosomes after entering the cells for 4 h. After CT26 cells were transfected with lip@PSD-siP, the PD-L1 positive cell rate decreased by 82.4%, and its PD-L1 knockdown effect was significantly stronger than the positive control Lipo3000-siP. In vivo studies showed that lip@PSD-siP-mediated mild PTT and efficient PD-L1 knockdown exhibited primary and distal tumor inhibition, metastasis delay, and rechallenged tumor inhibition. The treatment with lip@PSD-siP significantly promoted the maturation of dendritic cells in lymph nodes. The amount of T cell infiltration in the tumor tissues increased significantly, and the frequency of CD8+ T cells and CD4+ T cells was significantly higher than that of other groups. The percentage of immunosuppressive regulatory cells (Tregs) in the tumor tissue on the treatment side decreased by 88% compared to the PBS group, and the proportion of CD8+CD69+ T cells in the distal tumor tissue was 2.8 times that of the PBS group. The memory T cells of mice in the long-term antitumor model were analyzed. The results showed that after treatment with lip@PSD-siP, the frequency of effector memory T cells (Tem cells) significantly increased, suggesting the formation of immune memory.

Nanotherapeutics for the Myocardium: A Potential Alternative for Treating Cardiac Diseases

ABSTRACT

Cardiovascular diseases (CVDs) are the foremost cause of morbidity and mortality worldwide. Current clinical interventions include invasive approaches for progressed conditions and pharmacological assistance for initial stages, which has systemic side effects. Preventive, curative, diagnostic, and theranostic (therapeutic + diagnostic) approaches till date are not very useful in combating the ongoing CVD epidemic, which demands a promising efficient alternative approach. To combat the growing CVD outbreak globally, the ideal strategy is to make the therapeutic intervention least invasive and direct to the heart to reduce the bystander effects on other organs and increase the bioavailability of the therapeutics to the myocardium. The application of nanoscience and nanoparticle-mediated approaches have gained a lot of momentum because of their efficient passive and active myocardium targeting capability owing to their improved specificity and controlled release. This review provides extensive insight into the various types of nanoparticles available for CVDs, their mechanisms of targeting (eg, direct or indirect), and the utmost need for further development of bench-to-bedside cardiac tissue-based nanomedicines. Furthermore, the review aims to summarize the different ideas and methods of nanoparticle-mediated therapeutic approaches to the myocardium till date with present clinical trials and future perspectives. This review also reflects the potential of such nanoparticle-mediated tissue-targeted therapies to contribute to the sustainable development goals of good health and well-being.

Advances in mRNA therapeutics for cancer immunotherapy: From modification to delivery

RNA vaccines have demonstrated their ability to solve the issues posed by the COVID-19 pandemic. This success has led to the renaissance of research into mRNA and their nanoformulations as potential therapeutic modalities for various diseases. The potential of mRNA as a template for synthesizing proteins and protein fragments for cancer immunotherapy is now being explored. Despite the promise, the use of mRNA in cancer immunotherapy is limited by challenges, such as low stability against extracellular RNases, poor delivery efficiency to the target organs and cells, short circulatory half-life, variable expression levels and duration. This review highlights recent advances in chemical modification and advanced delivery systems that are helping to address these challenges and unlock the biological and pharmacological potential of mRNA therapeutics in cancer immunotherapy. The review concludes by discussing future perspectives for mRNA-based cancer immunotherapy, which holds great promise as a next-generation therapeutic modality.

Alginate-Chitosan Hydrogels Containing shRNA Plasmid for Inhibition of CTNNB1 Expression in Breast Cancer Cells

The hydrogels prepared with alginate and chitosan polymers were prepared to deliver the shRNA-encoding plasmid (pshRNA) to MDA-MB-231 cells for the inhibition of β-catenin (CTNNB1), which was reported to be overexpressed in breast cancer. Polyion complex hydrogels prepared using sodium alginate and chitosan were characterized by Fourier transform infrared spectrometry (FTIR) analysis, scanning electron microscope (SEM) analysis, swelling, and degradation properties. After the release properties and serum stability of pshRNA-loaded hydrogels were determined, their cytotoxicity, transfection efficacy, and effects on CTNNB1 expression were investigated in MDA-MB-231 cells. All hydrogels were shown to protect pshRNA from the enzymatic activity of serum and to deliver pshRNA to cells efficiently. As a result of transfection studies, pshRNA-loaded hydrogels reduced CTNNB1 expression by up to 30.25%. Cell viability also decreased by 38% in cells treated with 2.5% (w/v) alginate-chitosan hydrogel containing pshRNA targeting CTNNB1. Alginate-chitosan hydrogels were shown to be a suitable matrix system for local gene delivery.

Inhalation delivery of nucleic acid gene therapies in preclinical drug development

INTRODUCTION

Inhaled gene therapy programs targeting diseases of the lung have seen increasing interest in recent years, though as of yet no product has successfully entered the market. Preclinical research to support such programs is critically important in maximizing the chances of developing successful candidates.

AREAS COVERED

Aspects of inhalation delivery of gene therapies are reviewed, with a focus on preclinical research in animal models. Various barriers to inhalation delivery of gene therapies are discussed, including aerosolization stresses, aerosol behavior in the respiratory tract, and disposition processes post-deposition. Important aspects of animal models are considered, including determinations of biologically relevant determinations of dose and issues related to translatability.

EXPERT OPINION

Development of clinically-efficacious inhaled gene therapies has proven difficult owing to numerous challenges. Fit-for-purpose experimental and analytical methods are necessary for determinations of biologically relevant doses in preclinical animal models. Further developments in disease-specific animal models may aid in improving the translatability of results in future work, and we expect to see accelerated interests in inhalation gene therapies for various diseases. Sponsors, researchers, and regulators are encouraged to engage in early and frequent discussion regarding candidate therapies, and additional dissemination of preclinical methodologies would be of immense value in avoiding common pitfalls.

Chitosan-Based Nanoparticles for Nucleic Acid Delivery: Technological Aspects, Applications, and Future Perspectives

Chitosan is a naturally occurring polymer derived from the deacetylation of chitin, which is an abundant carbohydrate found mainly in the shells of various marine and terrestrial (micro)organisms. Chitosan has been extensively used to construct nanoparticles (NPs), which are biocompatible, biodegradable, non-toxic, easy to prepare, and can function as effective drug delivery systems. Moreover, chitosan NPs have been employed in gene and vaccine delivery, as well as advanced cancer therapy, and they can also serve as new therapeutic tools against viral infections. In this review, we summarize the most recent developments in the field of chitosan-based NPs intended as nucleic acid delivery vehicles and gene therapy vectors. Special attention is given to the technological aspects of chitosan complexes for nucleic acid delivery.

Targeted chitosan nanobubbles as a strategy to down-regulate microRNA-17 into B-cell lymphoma models

Introduction

MicroRNAs represent interesting targets for new therapies because their altered expression influences tumor development and progression. miR-17 is a prototype of onco-miRNA, known to be overexpressed in B-cell non-Hodgkin lymphoma (B-NHL) with peculiar clinic-biological features. AntagomiR molecules have been largely studied to repress the regulatory functions of up-regulated onco-miRNAs, but their clinical use is mainly limited by their rapid degradation, kidney elimination and poor cellular uptake when injected as naked oligonucleotides.

Methods

To overcome these problems, we exploited CD20 targeted chitosan nanobubbles (NBs) for a preferential and safe delivery of antagomiR17 to B-NHL cells.

Results

Positively charged 400 nm-sized nanobubbles (NBs) represent a stable and effective nanoplatform for antagomiR encapsulation and specific release into B-NHL cells. NBs rapidly accumulated in tumor microenvironment, but only those conjugated with a targeting system (antiCD20 antibodies) were internalized into B-NHL cells, releasing antagomiR17 in the cytoplasm, both in vitro and in vivo. The result is the down-regulation of miR-17 level and the reduction in tumor burden in a human-mouse B-NHL model, without any documented side effects.

Discussion

Anti-CD20 targeted NBs investigated in this study showed physico-chemical and stability properties suitable for antagomiR17 delivery in vivo and represent a useful nanoplatform to address B-cell malignancies or other cancers through the modification of their surface with specific targeting antibodies.

Biomaterial-based gene therapy

Gene therapy, a medical approach that involves the correction or replacement of defective and abnormal genes, plays an essential role in the treatment of complex and refractory diseases, such as hereditary diseases, cancer, and rheumatic immune diseases. Nucleic acids alone do not easily enter the target cells due to their easy degradation in vivo and the structure of the target cell membranes. The introduction of genes into biological cells is often dependent on gene delivery vectors, such as adenoviral vectors, which are commonly used in gene therapy. However, traditional viral vectors have strong immunogenicity while also presenting a potential infection risk. Recently, biomaterials have attracted attention for use as efficient gene delivery vehicles, because they can avoid the drawbacks associated with viral vectors. Biomaterials can improve the biological stability of nucleic acids and the efficiency of intracellular gene delivery. This review is focused on biomaterial-based delivery systems in gene therapy and disease treatment. Herein, we review the recent developments and modalities of gene therapy. Additionally, we discuss nucleic acid delivery strategies, with a focus on biomaterial-based gene delivery systems. Furthermore, the current applications of biomaterial-based gene therapy are summarized.

Polymer-Based mRNA Delivery Strategies for Advanced Therapies

Messenger RNA (mRNA)-based therapies offer great promise for the treatment of a variety of diseases. In 2020, two FDA approvals of mRNA-based vaccines have elevated mRNA vaccines to global recognition. However, the therapeutic capabilities of mRNA extend far beyond vaccines against infectious diseases. They hold potential for cancer vaccines, protein replacement therapies, gene editing therapies, and immunotherapies. For realizing such advanced therapies, it is crucial to develop effective carrier systems. Recent advances in materials science have led to the development of promising nonviral mRNA delivery systems. In comparison to other carriers like lipid nanoparticles, polymer-based delivery systems often receive less attention, despite their unique ability to carefully tune their chemical features to promote mRNA protection, their favorable pharmacokinetics, and their potential for targeting delivery. In this review, the central features of polymer-based systems for mRNA delivery highlighting the molecular design criteria, stability, and biodistribution are discussed. Finally, the role of targeting ligands for the future of RNA therapies is analyzed.

Mannose-functionalized star polycation mediated CRISPR/Cas9 delivery for lung cancer therapy

The survivin gene, highly expressed in most cancer cells, is closely associated with inhibiting apoptosis. Therefore, gene editing for the survivin gene has great potential in tumor therapy. However, it is difficult for plasmid DNA (pDNA) to be taken up directly by cells, and thus the construction of gene vectors is a key step for successful gene editing. Ethanolamine-functionalized polyglycidyl methacrylate (PGEA) has been proved to facilitate the transfection of pDNA into cells in both in vivo and in vitro experiments. However, PGEA does not specifically recognize tumor cells. Some tumor cells express more mannose receptor (MR) than healthy cells. To achieve efficient target and transfection, we designed mannose-functionalized four-arm PGEA cationic polymers (P(GEA-co-ManMA), GM) with different molecular weights. GM was combined with pCas9-survivin. The mannose unit of GM/pCas9-survivin was identified by MR to selectively enter lung cancer cells. In vitro experiments showed that GM not only had excellent biocompatibility, gene transfection performance, and targeted ability, but also significantly inhibited the proliferation of tumor cells when used in combination with pCas9-survivin. At the same time, we also studied the relationship between the molecular weight and therapeutic effect.

Anti-COVID-19 Credentials of Chitosan Composites and Derivatives: Future Scope?

Chitosan derivatives and composites are the next generation polymers for biomedical applications. With their humble origins from the second most abundant naturally available polymer chitin, chitosan is currently one of the most promising polymer systems, with wide biological applications. This current review gives a bird's eye view of the antimicrobial applications of chitosan composites and derivatives. The antiviral activity and the mechanisms behind the inhibitory activity of these components have been reviewed. Specifically, the anti-COVID-19 aspects of chitosan composites and their derivatives have been compiled from the existing scattered reports and presented. Defeating COVID-19 is the battle of this century, and the chitosan derivative-based combat strategies naturally become very attractive. The challenges ahead and future recommendations have been addressed.