Journal of Biological Engineering最新文献

To develop antimicrobial films for active food packaging applications, poly(butylene succinate) (PBS) was fabricated into films of varying thicknesses (50, 75 and 100 μm) and incorporated with different cymophenol concentrations (0 to 10 wt%). The results demonstrated that cymophenol functioned not only as an antimicrobial agent but also as a plasticizer, enhancing the essential properties required for food packaging films. The films effectively inhibited the growth of Staphylococcus aureus and Escherichia coli at cymophenol concentrations of 6 and 8 wt%, respectively. Both increased cymophenol content and film thickness contributed to improved mechanical properties, particularly by elevating stretchability. Release tests indicated that thicker films exhibited higher cymophenol migration, which correlated with an increased diffusion coefficient. Besides packaging film properties, the PBS/cymophenol plates, particularly at 100 μm thickness, presented an alternative function to enhance the shelf-life extension of strawberries by reducing yeast and mold growth. Soil microorganism vitality tests on sixteen isolated soil microbial strains showed that the antimicrobial films did not hinder the soil microbial population growth, confirming their potential to retain biodegradability. Additionally, the survival rates of brine shrimp after five days were significantly reduced when stored in PBS and PBS/cymophenol. Based on these findings, antimicrobial PBS/cymophenol films are proposed as sustainable, biodegradable active packaging materials that combine strong antimicrobial activity with environmental safety in terrestrial conditions and can be easily integrated into various food containers.

Auxin-derived carbon dots (Aux-CDs) were synthesized and evaluated for their dual functionality in biomedical and agricultural contexts. One-step hydrothermal synthesis was employed for the first time to produce eco-friendly and cost-effective Aux-CDs. The approach involves introducing a mixture of Auxin and water into the reactor. The fluorescence in the Aux-CDs was initially confirmed using a UV transilluminator. Physicochemical characterizations were evaluated via UV-Vis spectrophotometry (absorbance at 470 nm), zeta potential measurement (-37.8 mV), photoluminescence, scanning electron microscopy (SEM), and Fourier transform infrared (FT-IR). The total quantum yield exhibited was 43%, and the transmission electron microscopy (TEM) showed a size range of approximately 10 nm. In cancer cells, the MTT assay revealed that Aux-CDs demonstrated low cytotoxicity in 4T1 cells up to 10 µg/mL. The fluorescence accumulation indicates the internalization of the Aux-CDs by 4T1 cells. In seed performance, we examined the effects of Aux-CDs on through nanopriming. The wheat seeds (the Drum and Ehsan varieties) were incubated with CDs to check the absorption of Aux-CDs by them. The fluorescence was observed under a UV-transilluminator in the growing parts of seeds, indicating the absorption of Aux-CDs during wheat growth. Cancer cell and wheat imaging showed that fluorescent Aux-CDs could be used as a bioimaging agent. Additionally, Aux-CDs significantly improved seed germination percentage and the performance index in the Drum and Ehsan varieties in low concentration (1 µg/mL) compared to high concentration (10 µg/mL). Consequently, Aux-CDs synthesized via a one-step hydrothermal method exhibit high quantum yield and biocompatibility, and can act as multifunctional nanomaterials for bioimaging and plant growth enhancement in biomedical and agricultural research.

Background: Cellular impedance-based assays offer a sensitive, label-free, and non-destructive method to continuously monitor cells in real time, allowing the assessment of both kinetics and degree of migration for breast cancer cells. A scratch assay is one of the most commonly used methods for testing cell migration in a two-dimensional (2D) monolayer culture. Traditional methods to evaluate 2D cancer migration commonly use image analysis to determine the rate of wound closure over a set of timepoints as an indicator of migratory/metastatic potential for cancer cells. An impedance-based assay system was employed towards establishing a modified wound healing assay technique that can measure wound coverage and therefore, 2D cancer migration continuously. This method can also be used to measure a variety of cell characteristics, including proliferation and epithelial barrier integrity.

Results: Using the Maestro Z Live-cell Analysis System by Axion Biosystems, cell spread, related to single cell morphology, and cell proliferation were observed for multiple breast cancer cell lines. A distinct quantifiable difference in the behavior of aggressive triple-negative breast cancer cells (HCC1806, MDA-MB-231), compared to less aggressive luminal MCF7 cells was determined. With an established assay method, cells were then treated with pro-inflammatory cytokine leptin, which plays a crucial role in metabolism and epithelial to mesenchymal transition (EMT), to verify assay sensitivity. The effects of leptin concentration in media were measurable for MCF7 and HCC1806 cells, and cell barrier integrity was significantly higher in the luminal MCF7 cells as compared to the more aggressive triple-negative cell lines. Cell migration to close a physical wound was measured over 36 hours, with the modified wound healing assay providing quantifiable evidence that the more aggressive breast cancer cells migrated to close the gap.

Conclusions: This work validates the use of cellular impedance-based assay systems to evaluate multiple cell characteristics. In a single experiment, cell spread, cell proliferation, cell-cell barrier integrity, and 2D cell migration were able to be quantified. These findings parallel previously published data for cell migration of the specific cell lines used, while highlighting the role of leptin in cancer behavior. Overall, the potential for a bioelectronic impedance assay system was demonstrated and its validity in effectively detecting and quantifying cell behaviors was proven.

As technology and regulatory guidelines continue improve, insect cell expression system has gained increasing attention as promising and versatile platforms for production of biopharmaceuticals. This review provides a comprehensive overview of recent advances in this platform, with a focus on their applications in human and veterinary vaccines, therapeutic proteins, and structurally complex proteins for biomedical research. Special emphasis is placed on emerging strategies such as larval expression systems, baculovirus-mediated antigen displaying technologies, and the development of gene therapy vectors. Despite their growing utility, insect cell systems face critical technical bottlenecks that limit scalability, productivity, and regulatory compliance. We discuss recent innovations aimed at addressing these challenges, including improvements in baculovirus infection dynamics, the genome engineering, and bioprocess optimization at both upstream and downstream levels. By synthesizing current knowledge and technological trends, this review outlines future directions for unlocking the full potential of insect cell platforms in next generation biomanufacturing.

Deoxynivalenol (Dex), a widespread mycotoxin found in contaminated cereals, induces testicular dysfunction primarily through oxidative stress, inflammation, and activation of apoptotic pathways. Lycopene (Lyc), a natural antioxidant, offers cytoprotective potential but is limited by poor aqueous solubility and instability. To address these limitations, we developed a bioengineered injectable hydrogel system composed of hyaluronic acid and gelatin methacrylate, both natural biopolymers, to encapsulate exosomes preloaded with lycopene (HAMA-GelMA@Exo-Lyc) for controlled, localized delivery. Comprehensive characterization demonstrated successful integration of HAMA-GelMA@Exo-Lyc hydrogel, evidenced by a shifted amide I band at 1643.67 cm⁻¹ and a uniform porous network of 50-150 μm. The modified hydrogel exhibited improved mechanical strength (21.8 ± 1.6 kPa), faster gelation (95 ± 8 s), and enhanced water retention (85.7 ± 3.1%) compared to the unmodified HAMA/GelMA system. In vitro, GC-1 spg cells treated with HAMA-GelMA@Exo-Lyc hydrogel exhibited enhanced viability, maintaining over 79.0 ± 0.30% cell survival at 150 µg/mL after 24 h, alongside reduced ROS levels and improved proliferative capacity compared to free Lyc. In a Dex-induced testicular injury model, HAMA/GelMA@Exo-Lyc treatment restored serum testosterone levels, improved spermatogenic architecture, and significantly reduced oxidative stress markers. Elevated levels of GSH and CAT indicated an enhanced antioxidant defense, whereas reductions were noted in inflammatory mediators TNF-α and IL-1β, as well as in mitochondrial apoptosis-associated proteins, such as Cyt-c, Bax, and Caspase-3. Meanwhile, Bcl-2 expression rose, suggesting anti-apoptotic effects. These results suggest that HAMA-GelMA@Exo-Lyc represents a promising bioengineered platform for mitigating Dex-induced testicular damage by suppressing oxidative stress and modulating the apoptosis pathway.

Fracture healing complications, including nonunion, are common in polytrauma patients partly due to systemic inflammatory dysregulation. Although mesenchymal stem cells (MSCs) have been widely explored for their regenerative properties, their therapeutic potential in polytrauma patients remains uncertain. Given the clinical interest in both systemic and localized stem cell therapies, understanding how delivery route influences MSCs biodistribution, inflammatory modulation, and therapeutic efficacy is critical for optimizing treatment strategies in polytrauma. Hence, we compared systemic versus local MSCs delivery in a polytrauma model. We evaluated inflammatory responses and bone formation in a C57BL/6J murine model across four groups: (1) isolated fracture, (2) polytrauma (femur fracture + chest trauma), (3) polytrauma + systemic MSC delivery, and (4) polytrauma + local MSC delivery in hyaluronic acid-based hydrogels at the fracture site. Polytrauma induced a prolonged inflammatory response characterized by elevated interleukin 1 alpha and beta (IL-1α & β), tumor necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ), and monocyte chemoattractant protein-1 and - 5 (MCP-1 & MCP-5). Both delivery methods significantly reduced inflammation and proinflammatory cytokines, though local delivery yielded more consistent effects. IVIS imaging confirmed MSC retention at the fracture site in the local delivery group, while systemic administration of MSCs resulted in pulmonary entrapment. Although systemic MSCs failed to enhance fracture healing significantly, local MSC delivery promoted bone formation evidenced by CT and histological characterizations. These findings demonstrate that local MSC delivery in a hydrogel scaffold represents a superior strategy for improving fracture healing in polytrauma patients compared to systemic delivery.

Combinatorial expression libraries to optimize multigene pathways can improve product titers, but the large number of potential genetic variants makes exhaustive testing impractical. Statistical Design of Experiments (DoE) offers a powerful alternative to enable efficient exploration of gene expression landscapes with a limited number of measurements. Here, we applied this approach to modulate expression levels across all genes in the shikimate and para-aminobenzoic acid (pABA) biosynthesis pathways in Pseudomonas putida. From a theoretical library of 512 strain variants, we trained a regression model using a statistically structured sample comprising 2.7% of the total library, as defined by our DoE approach, and used the model to predict new genotypes with improved pABA titers. This strategy enabled us to achieve product titers ranging from 2 to 186.2 mg/L in the initial screen and subsequently guide a second round of strain engineering, culminating in a maximum titer of 232.1 mg/L. Our analysis indicated that aroB, encoding 3-dehydroquinate synthase, is a critical bottleneck in pABA biosynthesis. This study highlights the utility of combining DoE with linear regression modeling to systematically optimize complex metabolic pathways, paving the way for more efficient microbial production.