Frontiers in Bioengineering and Biotechnology最新文献

Induced pluripotent stem cell-derived cardiomyocytes have shown promise to be an essential tool for studying genetic cardiac diseases. However, their limited maturity remains a barrier to reaching their full potential. Many have challenged this problem; however, it is difficult to compare the results because the parameters for cardiomyocyte maturation are diverse, mostly relying on physiological experiments that display significant lab-to-lab variations and are labor-intensive, and are not comparable to maturing cardiomyocytes in vivo. Here, we propose a transcriptome-based scoring method for cardiomyocyte maturation. We first established the maturation score based on transcriptome of mouse ventricles from embryonic (day 11) to adult (10-month-old) ventricles. We then demonstrated that known maturation conditions increased the maturation scores of mouse embryonic stem cell-derived cardiomyocytes. We finally performed expression screening of 92 candidate transcriptional factors (TFs) and identified pro-maturation TFs, including peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC1α), PGC1β, and estrogen-related receptor alpha (ERRα). These results support that the transcriptome-based maturation score is a quantitative and reliable approach for identifying pro-maturation factors for cardiomyocytes.

Introduction: Electrospinning is a scalable technique for generating fibrous scaffolds with tunable micro- and nanoscale architectures for tissue engineering, drug delivery, and wound care. Machine learning (ML) has emerged as a powerful tool to accelerate process optimisation; however, existing models typically predict only mean fibre diameters, overlooking the entire diameter distribution that governs scaffold functionality and biomimicry. This study introduces FibreCastML, the first open-access, distribution-aware ML framework that predicts full fibre diameter spectra from routinely reported processing parameters and provides interpretable insights into parameter influence.

Methods: A comprehensive meta-dataset of 68,538 fibre-diameter measurements from 1,778 studies across 16 biomedical polymers was curated. Six standard input parameters (solution concentration, voltage, flow rate, tip-to-collector distance, needle diameter, and rotation speed) were used to train 7 ML learners (linear model, elastic net, decision tree, multivariate adaptive regression splines, k-Nearest Neighbours, random forest, and radial-basis Support Vector Machine) under nested cross-validation with leave-one-study-out external folds to ensure generalisable performance. Model interpretability combined variable importance, SHapley Additive exPlanations (SHAP), correlation matrices, and 3D parameter maps. The FibreCastML web app integrates these capabilities with out-of-range detection, solvent suggestions, and automated Excel reports.

Results: Non-linear and local learners consistently outperformed linear baselines, achieving R ² > 0.91 for polymers such as cellulose acetate, Nylon-6, Polyacrylonitrile, polyD,L-lactide, Polymethyl methacrylate, Polystyrene, Polyurethane, Polyvinyl alcohol and Polyvinylidene fluoride. Concentration emerged as the most influential variable globally. The FibreCastML app returns polymer-specific distribution plots, predicted-vs-observed diagnostics, feature importance and correlations, and transparent metrics (R ², RMSE, mean absolute error) for user-defined settings. In an experimental validation case using different electrospinners and microscopies, predicted diameter distributions closely matched experimental measurements (Kolmogorov-Smirnov p > 0.13 and overlap coefficient of 84%).

Discussion: By shifting from mean-centric to distribution-aware modelling, this work establishes a new paradigm for electrospinning design. FibreCastML enables reproducible, sustainable, and data-driven optimisation of scaffold architecture, bridging experimental and computational domains. Openly available, it empowers laboratories worldwide to perform faster, greener, and more reproducible electrospinning research, advancing sustainable nanomanufacturing and biomedical innovation.

Background: The architecture of bone substitute scaffolds-particularly pore size and organization-plays a crucial role in orchestrating immune responses, osteogenesis and angiogenesis. Yet, the mechanisms linking scaffold design to the temporal dynamics of bone regeneration remain partially understood. To address this, we established a refined in vivo model that integrates histological, molecular, and immunological analyses from a single explant, enabling spatially resolved insight into the bone healing process and dynamics.

Methods: Using a dynamic rabbit calvarial model, we investigated 3D-printed calcium phosphate cement scaffolds designed with concomitant macroarchitectures of 250 μm and 500 µm pores within a single construct, allowing direct intra-animal comparison. The model recapitulated three vertically migrating zones of regeneration-regenerative, osteogenic, and granulation-captured at 2 and 4 weeks. Histomorphometric analyses quantified bone ingrowth, while laser microdissection enabled zone-specific transcriptomic profiling from paraffin-embedded sections previously used for (immuno-)histology. Gene expression was further validated by qPCR and complemented with immunohistochemical characterization of macrophage and neutrophil populations.

Results: Histological analysis revealed a consistent spatial organization of bone regeneration across conditions. After 4 weeks, scaffolds with 250 µm pores exhibited more homogeneous and advanced bone formation than those with 500 µm pores or particulate substitutes. Transcriptomic analysis identified 280-381 differentially expressed genes between microporous architectures, with over half being non-coding RNAs, suggesting an important role for post-transcriptional regulation. Enrichment analyses indicated modulation of pathways involved in immune activity, ossification, calcium signaling and autophagy. Immunohistochemistry confirmed similar inflammatory mechanisms across both macroarchitectures but revealed earlier M1-to-M2 macrophage transition and faster inflammatory resolution with the finest porous network.

Conclusion: This integrative in vivo model provides a robust workflow for correlating structural, cellular, and molecular dimensions of bone regeneration within the same specimen. The findings show that scaffold macroarchitecture influences both the extent and timing of immune and osteogenic processes. While scaffolds with 250 μm and 500 µm pores supported regeneration, the finer design consistently promoted more advanced tissue formation and maturation. These results underscore the key role of scaffold design in modulating bone healing and highlight this model as a platform for studying structure-function relationships in bone tissue engineering.

Background: Sesuvium portulacastrum ("Pirrixiu") is a halophytic plant adapted to saline environments with potential wound-healing properties.

Objective: To evaluate the wound-healing efficacy of a 10% macerated S. portulacastrum gel compared with the topical antibiotic Nebacetin in Wistar rats with standardized excisional wounds.

Methods: Experimental, completely randomized study in Wistar rats. Wound area reduction was measured daily. The association between time and wound closure was assessed by linear regression. Histological evaluation (hematoxylin and eosin; Masson's trichrome) examined inflammation, collagen deposition, angiogenesis/vascularization, and re-epithelialization.

Results: Time was strongly associated with wound closure (correlation coefficient > 0.80; p < 0.05). S. portulacastrum-treated groups achieved mean wound area reductions of up to 75% during the experimental period and demonstrated significantly greater collagen deposition and re-epithelialization, comparable to the Nebacetin-treated group (p < 0.05). Angiogenesis/vascularization did not differ significantly between groups (p > 0.05). Inflammation was significantly reduced compared with the positive control (p < 0.05). No adverse events or signs of infection or stress were observed.

Conclusion: A 10% S. portulacastrum gel promoted wound healing with enhanced collagen deposition and re-epithelialization, showing effects comparable to Nebacetin. The findings support S. portulacastrum as a promising, low-cost, and potentially sustainable therapeutic alternative and reinforce the value of Caatinga biodiversity.

Development of efficient bioconversion processes is limited by the ability to predictably improve metabolic flux. Here we deployed Bayesian Metabolic Control Analysis as a platform to integrate multi-omics data with metabolic modeling and evaluated its ability to predict genetic interventions that improve metabolic flux. Global Metabolomics and proteomics data was collected from 17 Aspergillus niger strains engineered to produce the platform biochemical 3-hydroxypropionic acid from which seven actional genetic interventions were predicted from significant flux control coefficients. Of the suggested genetic interventions, two were present within the intuitively designed strains used for training (malonic semialdehyde dehydrogenase and pyruvate carboxylase) while five predicted targets were present within non-intuitive areas of the metabolic network including 5-formyltetrahydrofolate deformylase and four mitochondrial enzymes, alcohol dehydrogenase, succinyl-CoA ligase, aspartate aminotransferase, and malate dehydrogenase. Six of the targets were validated in the highest performing 3-HP strain used for multi-omics data generation which contained a prior disruption of the highest scoring target malonic semialdehyde dehydrogenase. Predicted directional perturbation of five of the six tested targets significantly improved titer and rate of 3-HP production and two significantly improved yield. The greatest improvements were observed following disruption of the non-intuitive target succinyl-CoA ligase which increased titer by 39% and yield by 29% (to 20.4 g/L 3-HP and 0.31 g 3-HP/g glucose) over the strains used for training. This study demonstrates the utility of Bayesian Metabolic Control Analysis and highlights the ability to predict meaningful genetic targets in unexpected areas of metabolism to improve engineered strains for bioconversion.

Introduction: Bacterial antibiotic resistance has emerged as a significant global threat, making it increasingly challenging to effectively treat infections in patients. Nanomedicine technologies can be implemented for the targeted delivery of medications and drugs to patients. This work investigates the use of silica nanoparticles (SiNPs) loaded with the clindamycin and tetracycline antibiotics to treat Staphylococcus epidermidis infection in a 3D-bioprinted dermal model. SiNPs are stable, biocompatible, and can be loaded with small molecules like antibiotics.

Methods: The SiNPs were synthesized and loaded with antibiotics. The loading efficiency of the SiNPs was determined by UV-Vis spectroscopy and high-performance liquid chromatography. Dome-shaped constructs containing fibroblasts were 3D printed using a fibrin-based bioink to mimic the dermis of skin. These constructs were then inoculated with bacterial cultures labeled with green fluorescent protein (GFP) 4 days post printing and then treated with antibiotic-loaded SiNPs to determine their effect on bacterial growth. After the incubation phase, the bacteria were cultured in broth to determine the colony-forming unit (CFU) count on toxin superantigen (TSA) plates containing 10 mg/mL chloramphenicol.

Results and discussion: The CFU count of the 3D-bioprinted human constructs samples treated with antibiotics was significantly lower than both the SiNP-treated and untreated samples. The results suggest that antibioticreleasing SiNPs can serve as a more efficient treatment for skin bacterial infections.

Introduction: The increase in thumb activity due to smartphone use in recent years may be associated with an elevated risk of developing musculoskeletal disorders. Prior studies on hand biomechanics during touchscreen use have indicated that activities such as swiping and tapping lead to varying levels of muscle activation and ranges of motion. Currently, however, there is no device that can be used readily to measure finger forces accurately during smartphone use.

Method: This study presents the design of a portable force plate specifically developed to quantify fingertip forces during smartphone use. The device utilises a load-cell structure and foil strain gauges to measure applied force magnitude, direction, and location.

Results: The device achieved a force sensitivity of 0.15 N and a positional sensitivity of 2.5 mm, with a maximum measurable force capacity of 3 N.

Discussion: The portable force plate enables the study of hand kinetics whilst allowing for physiological kinematics during smartphone use, with applications spanning musculoskeletal and finite-element model development of the hand, ergonomic risk assessment, smartphone interface evaluation, and musculoskeletal injury prevention.

Introduction: Current intestinal stents used to restore patency face limitations due to the rigidity of metal structures and the premature degradation of biopolymer alternatives. Therefore, there is a critical need to develop stents that are flexible, radially strong, and able to adapt to the dynamic conditions within the body.

Methods: This study introduces a novel tubular mechanical metamaterial featuring a sign-switchable Poisson's ratio and tunable mechanical properties, achieved by integrating hexagonal unit cells with positive Poisson's ratio and re-entrant unit cells with negative Poisson's ratio. Experimental uniaxial compression tests and finite element analyses were performed to validate the proposed design and assess its mechanical performance.

Results: The structure exhibits a negative Poisson's ratio under tensile loading across all configurations, whereas under compression, the Poisson's ratio was transited from negative to positive due to self-contact between triangular struts, enabling the distinctive sign-switching behavior. Experimental uniaxial compression tests and finite element analyses were performed to validate the proposed design and assess its mechanical performance. Results reveal that the geometric gap between the horizontal struts in the concave unit cells serves as a crucial tuning parameter: increasing this gap delays the onset of sign-switching during compression while exerting minimal influence on the tensile response. The stiffness, yield strength, and energy absorption capacity are shown to be highly adjustable through this geometric control.

Discussion: Overall, the metamaterial demonstrates superior energy absorption and tunable stiffness, making it a promising candidate for applications in intestinal stents.