Macromolecular bioscience最新文献

Wound healing is an intricate process that involves various biochemical pathways at each stage of tissue regeneration. Wound therapy is a series of distinct treatment stages that has a limited efficacy if wounds are of complex etiologies. A modern approach to this problem may be the development of bifunctional adaptive biohybrid systems that can concurrently affect pathogens' growth, inflammation, and tissue regeneration. We have developed biohybrid living material with antibacterial and regenerating properties based on induced hormesis by oxidative stress onto probiotic bacteria with prolonged synthesis of hydrogen peroxide, increased antibacterial action, and regeneration of the burn wound. Material demonstrates almost complete wound healing with a wound area difference 3–4 times with natural healing in vivo burn wound model for 21 days, antibacterial activity against wound antibiotic-resistance pathogens Escherichia coli K12 and Staphylococcus aureus ATCC 29213 in 4 and 5-fold, respectively in co-cultivation model, and has no toxicity to human skin fibroblasts and β-hemolysis in the in vitro model. Our findings promise the improving tissue regeneration of burn wounds, therapy against antibiotic-resistance pathogens by eliminating antibiotics, and other classical bactericides.

The current study introduces a novel hybrid system of polycaprolactone-nano beta-tricalcium phosphate microspheres (PCL-β-TCP Ms) combined with a hydrogel, which acts as a bone scaffold to accelerate osteogenic capabilities. This innovative system comprises a gelatin (Gel), oxidized dextran (Odex), and tannic acid (TA) hydrogel that integrates PCL-β-TCP microspheres. The Schiff base reaction between Gel and Odex, and the hydrogen bonding interaction of tannic acid and polymers, developed the hydrogel substrate. The process of fabricating the β-TCP-encapsulated PCL microspheres involved using the emulsion solvent evaporation technique, a method that allows for the encapsulation of bioactive substances within the microspheres. The findings revealed that incorporating microsphere-encapsulated β-TCP into the hydrogels notably enhanced their rheological properties, contributing to improved flow behavior and structural integrity. Additionally, the scanning electron microscopy (SEM) images illustrate that the addition of tannic acid leads to the development of a prominent fibrous structure within the hydrogels. This structural enhancement indicates that the presence of tannic acid plays a crucial role in modifying the hydrogel's composition at a microscopic level. The study investigated the interactions between biological cells and hybrid hydrogels in an in vitro setting. The viability and cytotoxicity testing demonstrated no adverse effects of the hybrid system (Gel/Odex/TA/PCL-β-TCP) and significantly improved preosteoblast cell (MC3T3-E1) viability. Moreover, the addition of these microspheres indicated a favorable environment for cell growth and development. Furthermore, Gel/Odex/TA/6%PCL-β-TCP Ms and Gel/Odex/TA/4%PCL-β-TCP Ms hydrogels exhibited a significant increase in calcium deposition and alkaline phosphatase (ALP) activity, respectively. These results reinforce that this multifunctional composite hydrogel may serve as a promising scaffold for bone tissue regeneration.

The development of bioinks tailored for corneal tissue engineering is crucial to replicating the native structure and function of the cornea. This study presents a scaffold-free extrusion-based 3D bioprinting (E3DB) approach to fabricate cornea constructs without support materials or molds. Bioinks composed of decellularized corneal extracellular matrix (dCECM), sodium alginate (SA), and type B gelatin (TBG) were formulated and evaluated for rheological performance, including viscosity, shear thinning, and viscoelasticity. Among the tested formulations, bioink 3G10 (SA: 3%, dCECM: 6/mL, TBG: 10%; 2:1:1 ratio) demonstrated optimal rheological and printability performance, enabling the fabrication of stable, curvature-preserving constructs. The printed constructs exhibited high shape fidelity, light transmittance comparable to native cornea, and Young's modulus values within the physiological range. Human placenta-derived mesenchymal stem cells (hPMSCs) encapsulated in bioink 3G10 showed high initial viability, a transient decline at day 7, and recovery by day 14, accompanied by morphological elongation. Gene expression analysis revealed marked upregulation of keratocyte-specific markers (KERA and ALDH) and suppression of ACTA2, indicating progression toward a keratocyte-like phenotype. These findings underscore the suitability of hPMSCs and dCECM-based bioinks for scaffold-free cornea bioprinting, providing a robust platform for the development of anatomically accurate and biologically functional corneal grafts.

The COVID-19 pandemic caused by the novel coronavirus SARS-CoV-2 has highlighted the critical need for safe and effective vaccines. In this study, subunit nanovaccine formulations were developed using the receptor-binding domain (RBD) of the SARS-CoV-2 spike (S) protein encapsulated in polymeric nanoparticles composed of poly(ethylene glycol)-block-poly(ε-caprolactone) (PEG-PCL). Two surfactants, poly(vinyl alcohol) (PVA) and sodium cholate (SC), were evaluated during formulation via a modified water-in-oil-in-water (w₁/o/w₂) emulsion-solvent evaporation method. The resulting nanoparticles were characterized for particle size, surface charge, encapsulation efficiency, and morphology. Optimized nanoparticles exhibited sizes below 300 nm, polydispersity indices less than 0.3, surface charges between ±10–20 mV, and encapsulation efficiencies exceeding 80%. SDS-PAGE confirmed structural integrity of the RBD, while in vitro release studies demonstrated sustained antigen release over time. Cellular response was assessed by measuring nitric oxide (NO) levels in dendritic cells, indicating comparable levels of cellular activation for both PVA- and SC-containing formulations. These findings demonstrate the potential of PEG-PCL-based nanovaccine systems for safe and stable delivery of viral antigens, offering a promising strategy for future vaccine development against COVID-19 and related pathogens.

This study investigates a multifunctional hydrogel system integrating carboxymethyl cellulose (CMC) in a 3D-printed limonene (LIM) scaffold coated with poly(3,4-ethylenedioxythiophene): polystyrene sulfonate (PEDOT:PSS). The system allows to enhance wound healing, prevent infections, and monitor the healing progress. CMC is crosslinked with citric acid (CA) to form the hydrogel matrix (CMC-CA), while the 3D-printed limonene (LIM) scaffold is embedded within the hydrogel to provide mechanical support. PEDOT:PSS and curcumin-loaded PEDOT (PEDOT:CUR) nanoparticles are integrated into the hydrogel-membrane system for electrochemical detection of bacterial infection and controlled delivery of the antibacterial drug. The CMC-CA hydrogel exhibits excellent mechanical properties, suitable for conforming to irregular wound surfaces. In addition to provide additional mechanical support, the LIM scaffold is used as a pillar for the incorporation of PEDOT The integration of PEDOT:PSS and PEDOT:CUR enable not only real-time monitoring of bacterial growth but also the electrostimulated release of curcumin, which demonstrates antibacterial activity against Escherichia coli and Staphylococcus aureus. Electrostimulation of the CMC-CA/LIM/PEDOT system promotes cell proliferation, supporting accelerated wound healing. In conclusion, the CMC-CA/LIM/PEDOT system combines mechanical support, infection monitoring, and enhanced healing through controlled drug delivery and electrical stimulation, addressing critical challenges in wound management.