Mammalian Cell Membrane Hybrid Polymersomes for mRNA Delivery.

Cell membranes are structures essential to the cell function and adaptation. Recent studies have targeted cell membranes to identify their protective and interactive properties. Leveraging these attributes of cellular membranes and their application to vaccine delivery is gaining increasing prominence. This study aimed to fuse synthetic polymeric nanoparticles with cell membranes to develop cell membrane hybrid polymersomes (HyPSomes) for enhanced vaccine delivery. We designed a platform to hybridize cell membranes with methoxy-poly(ethylene glycol)-block-polylactic acid nanoparticles by using the properties of both components. The formed HyPSomes were optimized by using dynamic light scattering, transmission electron microscopy, and Förster resonance energy transfer, and their stability was confirmed. The synthesized HyPSomes replicated the antigenic surface of the source cells and possessed the stability and efficacy of synthetic nanoparticles. These HyPSomes demonstrated enhanced cellular uptake and translation efficiency and facilitated endosome escape. HyPSomes showed outstanding capabilities for the delivery of foreign mRNAs to antigen-presenting cells. HyPSomes may serve as vaccine delivery systems by bridging the gap between synthetic and natural systems. These systems could be used in other contexts, e.g., diagnostics and drug delivery.

Exosome Isolation Using Chitosan Oligosaccharide Lactate-1-Pyrenecarboxylic Acid-Based Self-Assembled Magnetic Nanoclusters.

Exosomes are small extracellular vesicles that play a crucial role in intercellular communication and offer significant potential for a wide range of biomedical applications. However, conventional methods for exosome isolation have limitations in terms of purity, scalability, and preservation of exosome structural integrity. To address these challenges, an exosome isolation platform using chitosan oligosaccharide lactate conjugated 1-pyrenecarboxylic acid (COL-Py) based self-assembled magnetic nanoclusters (CMNCs), is presented. CMNCs are characterized to optimize their size, stability, and interaction dynamics with exosomes. The efficiency of CMNCs in isolating exosomes is systematically evaluated using various analytical methods to demonstrate their ability to capture exosomes based on amphiphilic lipid bilayers. CMNC-based exosome isolation consistently yields exosomes with structural integrity and purity similar to those obtained using traditional methods. The reusability of CMNCs over multiple exosome isolation cycles underscores their scalability and offers an efficient solution for biomedical applications. These results are supported by western blot analysis, which demonstrated the superiority of CMNC-based isolation in terms of purity compared to conventional methods. By providing a scalable and efficient exosome isolation process that preserves both structural integrity and purity, CMNCs can constitute a new platform that can contribute to the field of exosome studies.

Recent advances in microbial and enzymatic engineering for the biodegradation of micro- and nanoplastics.

This review examines the escalating issue of plastic pollution, specifically highlighting the detrimental effects on the environment and human health caused by microplastics and nanoplastics. The extensive use of synthetic polymers such as polyethylene (PE), polyethylene terephthalate (PET), and polystyrene (PS) has raised significant environmental concerns because of their long-lasting and non-degradable characteristics. This review delves into the role of enzymatic and microbial strategies in breaking down these polymers, showcasing recent advancements in the field. The intricacies of enzymatic degradation are thoroughly examined, including the effectiveness of enzymes such as PETase and MHETase, as well as the contribution of microbial pathways in breaking down resilient polymers into more benign substances. The paper also discusses the impact of chemical composition on plastic degradation kinetics and emphasizes the need for an approach to managing the environmental impact of synthetic polymers. The review highlights the significance of comprehending the physical characteristics and long-term impacts of micro- and nanoplastics in different ecosystems. Furthermore, it points out the environmental and health consequences of these contaminants, such as their ability to cause cancer and interfere with the endocrine system. The paper emphasizes the need for advanced analytical methods and effective strategies for enzymatic degradation, as well as continued research and development in this area. This review highlights the crucial role of enzymatic and microbial strategies in addressing plastic pollution and proposes methods to create effective and environmentally friendly solutions.

Dual-targeted nano-encapsulation of neonatal porcine islet-like cell clusters with triiodothyronine-loaded bifunctional polymersomes.

There is growing evidence that neonatal porcine islet-like cell clusters (NPCCs) isolated from piglets can be used to treat type 1 diabetes in humans. However, graft rejection is a common complication in humans owing to the prevalence of xenoantigens in porcine. Therefore, researchers have investigated various islet encapsulation techniques that could protect against these antigens. To this end, this study presents a robust nano-encapsulation method based on bifunctional polymersomes (PSomes), in which N-hydroxysuccinimide (NHS) and maleimide (Mal) groups conjugated to the PSomes terminal interact with the amine and thiol groups on the surface of NPCCs to induce dual targeting via two covalent bonds. The findings indicate that the ratio of NHS to Mal on PSomes is optimal for dual targeting. Moreover, triiodothyronine (T3) is known to promotes pancreatic islet maturation and differentiation of endocrine cells into beta cells. T3 encapsulated in PSomes is shown to increase the glucose sensitivity of NPCCs and enhance insulin secretion from NPCCs. Furthermore, improvements in the nano-encapsulation efficiency and insulin-secreting capability of NPCCs through dual targeting via dual-Psomes are demonstrated. In conclusion, the proposed nano-encapsulation technique could pave the way for significant advances in islet nano-encapsulation and the imprevement of NPCC immaturity via T3 release.

Charge-Complementary Polymersomes for Enhanced mRNA Delivery.

Messenger RNA (mRNA) therapies have emerged as potent and personalized alternatives to conventional DNA-based therapies. However, their therapeutic potential is frequently constrained by their molecular instability, susceptibility to degradation, and inefficient cellular delivery. This study presents the nanoparticle "ChargeSome" as a novel solution. ChargeSomes are designed to protect mRNAs from degradation by ribonucleases (RNases) and enable cell uptake, allowing mRNAs to reach the cytoplasm for protein expression via endosome escape. We evaluated the physicochemical properties of ChargeSomes using 1H nuclear magnetic resonance, Fourier-transform infrared, and dynamic light scattering. ChargeSomes formulated with a 9:1 ratio of mPEG-b-PLL to mPEG-b-PLL-SA demonstrated superior cell uptake and mRNA delivery efficiency. These ChargeSomes demonstrated minimal cytotoxicity in various in vitro structures, suggesting their potential safety for therapeutic applications. Inherent pH sensitivity enables precise mRNA release in acidic environments and structurally protects the encapsulated mRNA from external threats. Their design led to endosome rupture and efficient mRNA release into the cytoplasm by the proton sponge effect in acidic endosome environments. In conclusion, ChargeSomes have the potential to serve as effective secure mRNA delivery systems. Their combination of stability, protection, and delivery efficiency makes them promising tools for the advancement of mRNA-based therapeutics and vaccines.

Comparison of Graft Survival Between Full-Thickness and Lamellar Pig-to-Monkey Corneal Xenotransplantation from the Same Genetically Engineered Pig Model with Minimal Immunosuppression.

BACKGROUND: The graft survival rate of full-thickness corneal xenotransplantation (XTP) with minimal immunosuppression in genetically engineered pigs is unknown, whereas lamellar corneal XTP shows satisfactory results. We compared graft survival between full-thickness and lamellar transplantations in the same genetically engineered pig. METHODS: Six pig-to-monkey corneal transplantations were performed on 3 transgenic pigs. Two corneas harvested from 1 pig were transplanted into 2 monkeys using full-thickness and lamellar corneal xenotransplantation. The transgenic donor pigs used were α1,3-galactosyltransferase gene-knockout + membrane cofactor protein (GTKO+CD46) in one recipient and GTKO+CD46+ thrombomodulin (TBM) in the other. RESULTS: The graft survival time for GTKO+CD46 XTP was 28 days. With the addition of TBM, the survival differences between lamellar and full-thickness XTP were 98 days versus 14 days and >463 days (ongoing) versus 21 days, respectively. An excessive number of inflammatory cells was observed in failed grafts, but none were in the recipient's stromal bed. CONCLUSIONS: Unlike full-thickness corneal XTP, lamellar xenocorneal transplantation does not exhibit surgical complications, such as retrocorneal membrane or anterior synechia. The graft survival of lamellar XTP in this study was not as good as in our previous experiments, although the survival period was superior to that of full-thickness XTP. The difference in graft survival based on transgenic type is not definitive. Further studies using transgenic pigs and minimal immunosuppression need to focus on improving graft survival of lamellar XTP and using a larger sample size to determine the potential of full-thickness corneal XTP.

Current Status of Genetically Engineered Pig to Monkey Kidney Xenotransplantation in Korea.

BACKGROUND: In South Korea, pig-to-nonhuman primate trials of solid organs have only been performed recently, and the results are not sufficiently satisfactory to initiate clinical trials. Since November 2011, we have performed 30 kidney pig-to-nonhuman primate xenotransplantations at Konkuk University Hospital. METHODS: Donor αGal-knockout-based transgenic pigs were obtained from 3 institutes. The knock-in genes were CD39, CD46, CD55, CD73, and thrombomodulin, and 2-4 transgenic modifications with GTKO were done. The recipient animal was the cynomolgus monkey. We used the immunosuppressants anti-CD154, rituximab, anti-thymocyte globulin, tacrolimus, mycophenolate mofetil, and steroids. RESULTS: The mean survival duration of the recipients was 39 days. Except for a few cases for which survival durations were <2 days because of technical failure, 24 grafts survived for >7 days, with an average survival duration of 50 days. Long-term survival was observed 115 days after the removal of the contralateral kidney, which is currently the longest-recorded graft survival in Korea. We confirmed functioning grafts for the surviving transplanted kidneys after the second-look operation, and no signs of hyperacute rejection were observed. CONCLUSIONS: Although our survival results are relatively poor, they are the best-recorded results in South Korea, and the ongoing results are improving. With the support of government funds and the volunteering activities of clinical experts, we aim to further improve our experiments and contribute to the commencement of clinical trials of kidney xenotransplantation in Korea.

Application of Nanomaterials as an Advanced Strategy for the Diagnosis, Prevention, and Treatment of Viral Diseases.

The coronavirus disease (COVID-19) pandemic poses serious global health concerns with the continued emergence of new variants. The periodic outbreak of novel emerging and re-emerging infectious pathogens has elevated concerns and challenges for the future. To develop mitigation strategies against infectious diseases, nano-based approaches are being increasingly applied in diagnostic systems, prophylactic vaccines, and therapeutics. This review presents the properties of various nanoplatforms and discusses their role in the development of sensors, vectors, delivery agents, intrinsic immunostimulants, and viral inhibitors. Advanced nanomedical applications for infectious diseases have been highlighted. Moreover, physicochemical properties that confer physiological advantages and contribute to the control and inhibition of infectious diseases have been discussed. Safety concerns limit the commercial production and clinical use of these technologies in humans; however, overcoming these limitations may enable the use of nanomaterials to resolve current infection control issues via application of nanomaterials as a platform for the diagnosis, prevention, and treatment of viral diseases.