Magnetically-assisted viral transduction (magnetofection) medical applications: An update

Gene therapy involves replacing a faulty gene or adding a new gene inside the body's cells to cure disease or improve the body's ability to fight disease. Its popularity is evident from emerging concepts such as CRISPR-based genome editing and epigenetic studies and has been moved to a clinical setting. The strategy for therapeutic gene design includes; suppressing the expression of pathogenic genes, enhancing necessary protein production, and stimulating the immune system, which can be incorporated into both viral and non-viral gene vectors. Although non-viral gene delivery provides a safer platform, it suffers from an inefficient rate of gene transfection, which means a few genes could be successfully transfected and expressed within the cells. Incorporating nucleic acids into the viruses and using these viral vectors to infect cells increases gene transfection efficiency. Consequently, more cells will respond, more genes will be expressed, and sustained and successful gene therapy can be achieved. Combining nanoparticles (NPs) and nucleic acids protects genetic materials from enzymatic degradation. Furthermore, the vectors can be transferred faster, facilitating cell attachment and cellular uptake. Magnetically assisted viral transduction (magnetofection) enhances gene therapy efficiency by mixing magnetic nanoparticles (MNPs) with gene vectors and exerting a magnetic field to guide a significant number of vectors directly onto the cells. This research critically reviews the MNPs and the physiochemical properties needed to assemble an appropriate magnetic viral vector, discussing cellular hurdles and attitudes toward overcoming these barriers to reach clinical gene therapy perspectives. We focus on the studies conducted on the various applications of magnetic viral vectors in cancer therapies, regenerative medicine, tissue engineering, cell sorting, and virus isolation.

Therapeutic potential of gene therapy for gastrointestinal diseases: Advancements and future perspectives

Advancements in understanding the pathogenesis mechanisms underlying gastrointestinal diseases, encompassing inflammatory bowel disease, gastrointestinal cancer, and gastroesophageal reflux disease, have led to the identification of numerous novel therapeutic targets. These discoveries have opened up exciting possibilities for developing gene therapy strategies to treat gastrointestinal diseases. These strategies include gene replacement, gene enhancement, gene overexpression, gene function blocking, and transgenic somatic cell transplantation. In this review, we introduce the important gene therapy targets and targeted delivery systems within the field of gastroenterology. Furthermore, we provide a comprehensive overview of recent progress in gene therapy related to gastrointestinal disorders and shed light on the application of innovative gene-editing technologies in treating these conditions. These developments are fueling a revolution in the management of gastrointestinal diseases. Ultimately, we discuss the current challenges (particularly regarding safety, oral efficacy, and cost) and explore potential future directions for implementing gene therapy in the clinical settings for gastrointestinal diseases.

Polyester urethane urea (PEUU) functionalization for enhanced anti-thrombotic performance: advancing regenerative cardiovascular devices through innovative surface modifications

Introduction: Thrombogenesis, a major cause of implantable cardiovascular device failure, can be addressed through the use of biodegradable polymers modified with anticoagulating moieties. This study introduces a novel polyester urethane urea (PEUU) functionalized with various anti-platelet deposition molecules for enhanced antiplatelet performance in regenerative cardiovascular devices. Methods: PEUU, synthesized from poly-caprolactone, 1,4-diisocyanatobutane, and putrescine, was chemically oxidized to introduce carboxyl groups, creating PEUU-COOH. This polymer was functionalized in situ with polyethyleneimine, 4-arm polyethylene glycol, seleno-L-cystine, heparin sodium, and fondaparinux. Functionalization was confirmed using Fourier-transformed infrared spectroscopy and X-ray photoelectron spectroscopy. Bio-compatibility and hemocompatibility were validated through metabolic activity and hemolysis assays. The anti-thrombotic activity was assessed using platelet aggregation, lactate dehydrogenase activation assays, and scanning electron microscopy surface imaging. The whole-blood clotting time quantification assay was employed to evaluate anticoagulation properties. Results: Results demonstrated high biocompatibility and hemocompatibility, with the most potent anti-thrombotic activity observed on pegylated surfaces. However, seleno-L-cystine and fondaparinux exhibited no anti-platelet activity. Discussion: The findings highlight the importance of balancing various factors and addressing challenges associated with different approaches when developing innovative surface modifications for cardiovascular devices.

Micellar Polymer Magnetic Microrobots as Efficient Nerve Agent Microcleaners

Micro-/nanorobot technology has developed rapidly in recent years due to their great potential to perform multiple tasks. Here, we develop magnetic microrobots prepared as polycaprolactone/Fe₃O₄ microspheres covered by micellar polyethyleneimine and use them to efficiently remove a nerve agent from contaminated water. The magnetic polymeric microrobots presented in this work removed around 60% of the nerve agent from water samples in a short time. The attractive performance of these magnetic microrobots offers a very promising approach to large-scale water treatment for environmental remediation.

Intranasal delivery of plasmids expressing bovine herpesvirus 1 gB/gC/gD proteins by polyethyleneimine magnetic beads activates long-term immune responses in mice

Background

DNA vaccine is one of the research hotspots in veterinary vaccine development. Several advantages, such as cost-effectiveness, ease of design and production, good biocompatibility of plasmid DNA, attractive biosafety, and DNA stability, are found in DNA vaccines.

Methods

In this study, the plasmids expressing bovine herpesvirus 1 (BoHV-1) gB, gC, and gD proteins were mixed at the same mass ratio and adsorbed polyethyleneimine (PEI) magnetic beads with a diameter of 50 nm. Further, the plasmid and PEI magnetic bead polymers were packaged into double carboxyl polyethylene glycol (PEG) 600 to use as a DNA vaccine. The prepared DNA vaccine was employed to vaccinate mice via the intranasal route. The immune responses were evaluated in mice after vaccination.

Results

The expression of viral proteins could be largely detected in the lung and rarely in the spleen of mice subjected to a vaccination. The examination of biochemical indicators, anal temperature, and histology indicated that the DNA vaccine was safe in vivo. However, short-time toxicity was observed. The total antibody detected with ELISA in vaccinated mice showed a higher level than PBS, DNA, PEI + DNA, and PBS groups. The antibody level was significantly elevated at the 15th week and started to decrease since the 17th week. The neutralizing antibody titer was significantly higher in DNA vaccine than naked DNA vaccinated animals. The total IgA level was much greater in the DNA vaccine group compared to other component vaccinated groups. The examination of cellular cytokines and the percentage of CD4/CD8 indicated that the prepared DNA vaccine induced a strong cellular immunity.

Conclusion

The mixed application of plasmids expressing BoHV-1 gB/gC/gD proteins by nano-carrier through intranasal route could effectively activate long-term humoral, cellular, and mucosal immune responses at high levels in mice. These data indicate PEI magnetic beads combining with PEG600 are an efficient vector for plasmid DNA to deliver intranasally as a DNA vaccine candidate.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12985-021-01536-w.

Hierarchically Releasing Bio-Responsive Nanoparticles for Complete Tumor Microenvironment Modulation via TGF-β Pathway Inhibition and TAF Reduction

The aggressive progression of breast cancer is impacted significantly by the tumor microenvironment (TME). The current chemotherapy normally causes cytotoxicity to tumor cells, while does not effectively modulate the TME. Thus, the chemotherapy effect of breast cancer is usually dissatisfactory. In this study, a kind of hierarchically releasing bio-responsive nanoparticles (R(D)/H(S) NPs), constructed by β-cyclodextrin-grafted heparin and pH-sensitive pseudorotaxane, were investigated to enhance the breast cancer chemotherapeutic efficacy through TME modulation. Doxorubicin (DOX) and transforming growth factor-β (TGF-β) receptor inhibitor (SB431542) loaded onto R(D)/H(S) NPs were released rapidly for the respective response to low pH in endosomes/lysosomes and heparanase (HPSE) in TME. Our results showed that R(D)/H(S) NPs effectively inhibited the formation of tumor-associated fibroblasts (TAFs) and reduced TGF-β and collagen I secretion. Besides, the immunosuppressive microenvironment was effectively reversed into immunogenic, characterized by increased CD8⁺ and CD4⁺ T cell infiltration, which distinctly inhibited breast cancer metastasis. Therefore, R(D)/H(S) NPs remodeled the TME by downregulating TAFs, TGF-β, and collagen I; activating the immune microenvironment; and then amplifying the chemotherapeutic efficacy of DOX.

PEI fluorination reduces toxicity and promotes liver-targeted siRNA delivery

Polyethyleneimine (PEI) has been extensively investigated as an efficient carrier for nucleic acid delivery. Yet, it suffers from a high toxicity profile that hinders clinical translation. Fluorination has proven to be a valid approach to reduce the cytotoxicity of PEI and improve the in vitro siRNA delivery potency. Hydrophobicity and lipophobicity can be controllably introduced into the side chains of PEI. However, the effect of fluorination on siRNA delivery in vivo, particularly the biodistribution of siRNA polyplex nanoparticles with fluorinated PEIs, has not been extensively explored. Here, we introduce two series of fluorinated PEIs via amidation with ethyl trifluoroacetate and perfluorobutyryl chloride. Fluorination substantially improved the performance of PEI for siRNA delivery by reducing the cytotoxicity to MDA-MB-231 cells. Importantly, fluorinated PEI enabled the major accumulation of siRNA polyplex nanoparticles in the liver while non-fluorinated PEI delivered siRNA nanoparticles mainly to the lungs after intravenous administration to mice. It is envisioned that fluorination may be an important general strategy for lowering toxicity of cationic polymers, and that the fluorination-induced alteration of biodistribution may be applicable for improved delivery to different organs. Graphical abstract.

Principles and applications of nanomaterial-based hyperthermia in cancer therapy

Over the past few decades, hyperthermia therapy (HTT) has become one of the most promising strategies to treat cancer. HTT has been applied with nanotechnology to overcome drawbacks such as non-selectivity and invasiveness and to maximize therapeutic efficacy. The high temperature of HTT induces protein denaturation that leads to apoptosis or necrosis. It can also enhance the effects of other cancer therapies because heat-damaged tissues reduce radioresistance and help accumulate anticancer drugs. Gold nanoparticles and superparamagnetic iron oxide with different energy sources are commonly used as hyperthermia agents. New types of nanoparticles such as those whose surface is coated with several polymers and those modified with targeting moieties have been studied as novel HTT agents. In this review, we introduce principles and applications of nanotechnology-based HTT using gold nanoparticles and superparamagnetic iron oxide.

Carbon quantum dots and their biomedical and therapeutic applications: a review

In recent years, nano carbon quantum dots (CQDs) have received increasing attention due to their properties such as small size, fluorescence emission, chemical stability, water solubility, easy synthesis, and the possibility of functionalization. CQDs are fluorescent 0D carbon nanostructures with sizes below 10 nm. The fluorescence in CQDs originates from two sources, the fluorescence emission from bandgap transitions of conjugated π-domains and fluorescence from surface defects. The CQDs can emit fluorescence in the near-infrared (NIR) spectral region which makes them appropriate for biomedical applications. The fluorescence in these structures can be tuned with respect to the excitation wavelength. The CQDs have found applications in different areas such as biomedicine, photocatalysis, photosensors, solar energy conversion, light emitting diodes (LEDs), etc. The biomedical applications of CQDs include bioimaging, drug delivery, gene delivery, and cancer therapy. The fluorescent CQDs have low toxicity and other exceptional physicochemical properties in comparison to heavy metals semiconductor quantum dots (QDs) which make them superior candidates for biomedical applications. In this review, the synthesis routes and optical properties of the CQDs are clarified and recent advances in CQDs biomedical applications in bioimaging (in vivo and in vitro), drug delivery, cancer therapy, their potential to pass blood-brain barrier (BBB), and gene delivery are discussed.

Lipidoid iron oxide nanoparticles are a platform for nucleic acid delivery to the liver

Targeted delivery of antisense drugs is a promising technology which can provide a platform for the development of highly effective therapeuticals against a broad range of diseases. Insufficient stability of RNA in biological media coupled with hydrophilicity that prevents the molecule from penetrating cell membranes considerably limit RNA application in clinical practice. The aim of this work was to design a system for antisense drug delivery to liver hepatocytes using lipidoid magnetic nanoparticles (LNP). Nanocubes (NC) with average sizes of 16 and 27 nm were synthesized through decomposition of iron (III) oleate under high temperature conditions and functionalized with a cationic lipidoid С12-200. Magnetic NC demonstrated good MR-contrasting properties. Biodistribution of LNP was studied in vivo in BALB/c mice using the MR scanner. Additionally, liver sections obtained from the mice were subjected to histological examination. Nanoparticles of smaller size did not have a cytotoxic effect on HepG2 and Huh7 cell lines, whereas for larger NC, IC50 was 21.5 μg/ml and 126 μg/ml for HepG2 and Huh7 cells, respectively. Smaller particles tended to accumulate in hepatocytes. Bigger NC mainly accumulated in the spleen but also ended up in liver macrophages. This fact can be explained by a bigger hydrodynamic size of nanoparticles with a bigger magnetic core. Particles with smaller cores are a more effective platform for the delivery of antisense drugs to hepatocytes.

Fusion of gelonin and anti-insulin-like growth factor-1 receptor (IGF-1R) affibody for enhanced brain cancer therapy

Owing to the extraordinary potency in inhibiting protein translation that could eventually lead to apoptosis of tumor cells, ribosome-inactivating proteins (RIPs) such as gelonin have been considered attractive drug candidates for cancer therapy. However, due to several critical obstacles (e.g., severe toxicity issues caused by a lack of selectivity in their mode of action and the low cytotoxicity via poor cellular uptake, etc.), clinical application of RIPs is yet far from being accomplished. To overcome these challenges, in the present study, we engineered gelonin fusion proteins with anti-insulin-like growth factor-1 receptor (IGF-1R) affibody ("IAFF") via the genetic recombinant method and the SpyCatcher/SpyTag-mediated conjugation method. To this end, recombinant gelonin-anti-IGF-1R affibody (rGel-IAFF), gelonin-SpyCatcher (Gel-SpyCatcher) and SpyTag-IAFF fusion proteins were produced from the E. coli expression system, and gelonin-IAFF conjugate was synthesized by mixing Gel-SpyCatcher and SpyTag-IAFF. After preparation of both rGel-IAFF and Gel-IAFF conjugate, their components' functionality was characterized in vitro. Our assay results confirmed that, while both Gel-IAFF and Gel-SpyCatcher retained equipotent N-glycosidase activity to that of gelonin, IAFF was able to selectively bind to IGF-1R overexpressed U87 MG brain cancer cells over low expression LNCaP cells. The results of cellular analyses showed that rGel-IAFF and Gel-IAFF conjugate both exhibited a greater cell uptake in the U87 MG cells than gelonin, but not in the LNCaP cells, yielding a significantly augmented cytotoxicity only in the U87 MG cells. Remarkably, rGel-IAFF and Gel-IAFF conjugate displayed 22- and 5.6-fold lower IC₅₀ values (avg. IC₅₀: 180 and 720 nM, respectively) than gelonin (avg. IC₅₀: 4000 nM) in the U87 MG cells. Overall, the results of the present research demonstrated that fusion of gelonin with IAFF could provide an effective way to enhance the anti-tumor activity, while reducing the associated toxicity of gelonin.

Synthesis, characterization, and biological verification of anti-HER2 indocyanine green-doxorubicin-loaded polyethyleneimine-coated perfluorocarbon double nanoemulsions for targeted photochemotherapy of breast cancer cells

Background

Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer death among females worldwide. Among various types of breast cancer, the human epidermal growth factor receptor 2 (HER2)-overexpressing breast cancer is known to be more aggressive and often resistant to medicinal treatment, leading to an insufficient prognosis and poor susceptibility to chemotherapy and/or hormonal therapy in the current clinic. These circumstances implicate that developing an improved therapeutic strategy rather than persistently changing the anticancer drugs for trying is truly needed to successfully cure this type of breast cancer. In this study, we aimed to fabricate anti-HER2 indocyanine green (ICG)–doxorubicin (DOX)-loaded polyethyleneimine-coated perfluorocarbon double nanoemulsions (HIDPPDNEs) to explore the co-administration of phototherapy and chemotherapy for HER2-overexpressing breast cancer in vitro.

Results

The HIDPPDNE was first characterized as a sphere-like nanoparticle with surface charge of −57.1 ± 5.6 mV and size of 340.6 ± 4.5 nm, whereas the DOX release rates for the nanodroplets within 48 h in 4 and 37 °C were obtained by 8.13 ± 2.46% and 19.88 ± 2.75%, respectively. We then examined the target-ability of the nanostructure and found that the adhesion efficiency of the HIDPPDNEs onto HER2+ MDA-MB-453 cells was threefold higher than the nanodroplets without anti-HER2 antibody, indicating that the HIDPPDNEs are the product with HER2 binding specificity. In comparison to freely dissolved ICG, the HIDPPDNEs conferred an enhanced thermal stability to the entrapped ICG, and were able to provide a comparable hyperthermia effect and markedly increased production of singlet oxygen under near infrared irradiation (808 nm; 6 W/cm²). Based on the viability analyses, the results showed that the HIDPPDNEs were effective on cell eradication upon near infrared irradiation (808 nm; 6 W/cm²), and the resulting cell mortality was even higher than that caused by using twice amount of encapsulated DOX or ICG alone.

Conclusions

This work demonstrates that the HIDPPDNEs are able to provide improved ICG stability, binding specificity, and enhanced anticancer efficacy as compared to equal dosage of free ICG and/or DOX, showing a high potential for use in HER2 breast cancer therapy with reduced chemotoxicity.

Electronic supplementary material

The online version of this article (doi:10.1186/s12951-017-0274-5) contains supplementary material, which is available to authorized users.

SPIONs/DOX loaded polymer nanoparticles for MRI detection and efficient cell targeting drug delivery

Reducible polydopamine coated magnetic nanoparticles (SPIONs@PDA) for both magnetic resonance imaging (MRI) detection and cell targeting drug delivery.

Size-Shifting Micelle Nanoclusters Based on a Cross-Linked and pH-Sensitive Framework for Enhanced Tumor Targeting and Deep Penetration Features

The antitumor effect of chemotherapeutics loaded micelles mainly depends on two aspects: the accumulation in the tumor region and the penetration into the tumor interior. These two processes have different demands on particle size. The optimal particle size for enhanced permeability and retention (EPR) is commonly believed to be around 100 nm, while much smaller size is desired for deeper penetration into the tumor interior. To address these two different requirements, we constructed size-shifting micelle nanoclusters (MNC) based on a cross-linked framework interspersed with micelles. The particle size of the micelles was 14.6 ± 0.8 nm and increased to 104.2 ± 8.1 nm after the MNC were formed, leading to an effective utilization of the EPR effect. MNC were shifted to independent micelles in lysosomes, so that a more favorable particle size for penetration could be realized. The results of antitumor growth in vivo demonstrated that size-shifting MNC were more beneficial for tumor therapy than micelles.