Frontiers in Bioengineering and Biotechnology最新文献

Globally, esophageal cancer (EC) is the seventh most commonly diagnosed cancer and the sixth leading cause of cancer-related death. However, its treatment remains challenging due to significant obstacles. Photothermal therapy (PTT), a minimally invasive technique, has emerged as a promising method for tumor ablation. However, its efficacy is limited by low photothermal conversion efficiency and poor tissue penetration. To address these limitations, this study developed a metal-organic framework (MOF)-based nanozyme for the treatment of EC. In this system, the dye IR780, used for photothermal conversion, was encapsulated in liposomes and anchored onto the MOF nanozyme, resulting in a Pt@MOF@PSs construct that improved the aqueous stability of IR780. This multifunctional nanozyme showed tumor-targeting and synergistic therapeutic effects. After passive accumulation in EC tissues, Pt@MOF@PSs suppressed hypoxia and promoted reactive oxygen species (ROS) production by using the high H₂O₂ levels typical of the tumor microenvironment. The PTT activity of Pt@MOF@PSs was confirmed by its significant temperature increase and upregulation of heat shock protein 70 after irradiation with an 808 nm near-infrared laser. These features facilitated the effective modulation of the resistant tumor microenvironment, induced localized hyperthermia, exerted potent cytotoxicity against esophageal squamous carcinoma cells (ESCs), and suppressed EB tumor progression. These findings highlight Pt@MOF@PSs as a promising therapeutic option, integrating hypoxia relief, ROS generation, and PTT for improved therapeutics against EC.

Background: 3D printing enables the fabrication of customized breast phantoms for image quality assessment in digital mammography (DM) and digital breast tomosynthesis (DBT). A major challenge is the absence of standardized, accessible methods to characterize the attenuation properties of 3D-printed materials under clinical DM/DBT spectra.

Methods: An experimental framework was implemented to determine the effective X-ray attenuation coefficient (μ _eff ) of six 3D-printed polymers (PLA, PET, resin, ABS, ABS+, HIPS) and reference breast tissue-equivalent materials (CIRS plates simulating different breast glandular/adipose ratios (BR) and PMMA) using two commercial DM/DBT systems, with and without anti-scatter grid. Step-wedges (0.5-5.5 cm) were imaged across multiple kVp and filter settings. The μ _eff were obtained from measurements on images and fitted to an empirical model yielding μ ₀ (attenuation at thickness tending to zero) and k (decay rate) to characterize beam hardening and scatter influences. 3D-reference material equivalences were evaluated based on μ _eff and μ ₀ .

Results: Beam hardening and scatter reduced μ _eff with thickness, by 6%-14% with grid and 12%-28% without grid, with scatter contributing 47%-76% of the reduction in no-grid acquisitions. No significant differences were observed between the two mammography systems. Based on μ _eff values, attenuation equivalences (within ±6%) were identified between 3D-printed and reference breast tissue-equivalent materials: PLA with BR 100/0; PET and resin with BR 70/30 and PMMA; ABS+ with BR 30/70 and BR 50/50. ABS and HIPS showed larger mismatches. The empirical model achieved excellent fits (R² > 0.99), with μ ₀ values preserving attenuation ranking and enabling derivation of equivalent glandular proportions.

Conclusion: This framework demonstrates that routine clinical mammography systems can be used directly, without specialized instrumentation, to characterize 3D-printed materials as tissue surrogates. Several low-cost, widely available polymers were shown to reproduce breast tissue attenuation, supporting the local fabrication of anthropomorphic breast phantoms for realistic and clinically relevant image quality evaluation.

The glenoid labrum is a fibrocartilaginous structure essential for shoulder stability, yet its regeneration remains an unmet clinical challenge. Current surgical approaches restore initial joint stability but frequently fail to reestablish native biomechanics, leading to recurrence and early degenerative changes. In this study, we investigated the feasibility of fabricating a patient-specific, anatomically scaled glenoid labrum scaffold using digital modeling based on magnetic resonance imaging and 3D cryo(bio)printing of a gelatin methacryloyl (GelMA) hydrogel. Printing was performed in a temperature-controlled platform (22.5 °C, 15 °C, and -20 °C) to evaluate the influence of thermal conditions on structural fidelity and biological performance. Quantitative analyses showed that cryogenic deposition markedly improved printing precision, reducing filament spreading and enhancing geometric accuracy in both sharp-angle and grid-pattern evaluations. Biological assays indicated high viability of human mesenchymal stem cells under all temperature conditions, validating the cytocompatibility of the methodology. Morphological assessment by structured-light 3D scanning demonstrated that bioprinted patient-specific scaffold at -20 °C achieved the highest correspondence to the digital reference model. Overall, the integration of anatomical modeling with cryo(bio)printing proved to be an effective approach for producing anatomically faithful, patient-tailored scaffolds. This study presents the first demonstration of human glenoid labrum bioprinting and establishes a foundation for future translational research in fibrocartilaginous tissue regeneration.

Due to their special molecular weight and pharmacokinetic/pharmacodynamic (PK/PD) characteristics, antibody drugs have difficulty crossing the body barrier and entering complex microenvironments to provide effective treatment for encephalopathy, cancer, and severe infectious diseases. With the development and application of nanotechnology, drugs can be modified by nanomethods to increase the delivery efficiency, targeting, and permeability, reduce the resistance to the antibody, and improve the response rate, thus increasing their safety and effectiveness. Therefore, nanoparticles have extensive research and application value in drug delivery systems. This article summarizes the characteristics of nanoparticles and nanoantibody delivery systems to provide a reference for the future application of nanoparticles in drug delivery.

Background: Adenoid hypertrophy (AH) is a leading cause of pediatric obstructive sleep apnea, yet first-line diagnostics are invasive or resource-intensive. We developed and externally tested a low-cost, noninvasive screening model that fuses quantitative voice features with routine clinical variables for pre-endoscopy and primary-care triage.

Methods: In a dual-center cross-sectional study (N = 202), Center 1 (Capital Center for Children's Health, Capital Medical University, n = 161) served as the development cohort and Center 2 (College of Otolaryngology Head and Neck Surgery, The 6th Medical Center, National Clinical Research Center for Otolaryngologic Diseases, Chinese PLA General Hospital, Beijing, China, n = 41) as the independent external cohort. Children produced sustained/a/phonations; Mel-frequency cepstral coefficients (MFCCs) were summarized into fixed statistics and combined with readily available clinical information. Modeling used patient-level aggregation with stratified 10-fold cross-validation in development. The final classifier was selected by a joint criterion of AUC and average precision (AP), then a single Youden-derived locked cutoff was determined in the development set and applied unchanged to the external cohort. Discrimination (AUC/AP), calibration (Brier score, slope, intercept), and clinical utility were evaluated.

Results: Internal performance was stable (AUC = 0.81; AP = 0.84). On the small external cohort, discrimination remained (AUC = 0.79; AP = 0.88). At the locked cutoff, the model achieved clinically actionable sensitivity/specificity with balanced F1. Calibration was acceptable (Brier = 0.20, slope = 0.71, intercept = 0.94). Decision-curve analysis showed positive net benefit across a wide range of threshold probabilities versus "treat-all" and "treat-none." SHAP explainability indicated MFCC variability-related features and a subset of airway-symptom clinical variables as leading contributors, aligning with hyponasal resonance changes in AH.

Conclusion: A patient-level model with a locked decision threshold showed preservation of discrimination in a small external cohort, supporting a practical pathway for noninvasive, low-overhead AH triage prior to nasoendoscopy. Prospective multicenter studies are warranted.

Introduction: Effective cryopreservation is essential for the clinical application and large-scale banking of mesenchymal stem cells (MSCs). This study compares the performance of a novel DMSO-free cryoprotectant, XT-Thrive®, with a conventional DMSO-based solution, CryoStor® CS10, in preserving both commercial and donor-derived bone marrow MSCs (BM-MSCs). Evaluations focused on viability, recovery, proliferation, and functional characteristics across master cell bank (MCB), working cell bank (WCB), and final product (FP) stages.

Methods: In Part 1, commercial BM-MSCs were cryopreserved in XT-Thrive or CS10 and evaluated for pre-freeze viability, post-thaw survival (up to 6 h), and recovery in 2D and 3D cultures. In Part 2, donor-derived BM-MSCs were cryopreserved at passages 2 (MCB), 4 (WCB), and 8 (FP), and assessed for cumulative population doubling levels (cPDL), immunophenotype, clonogenicity, differentiation potential, secretome profile, telomere length, karyotype stability, and tumorigenicity.

Results: XT-Thrive-preserved MSCs maintained >90% pre-freeze viability after 24-h room temperature holding, compared to a ∼40% drop with CS10. Post-thaw viability at 6 h remained above 85% with XT-Thrive, vs. 60%-70% with CS10. In 3D microcarrier cultures under serum-free conditions, XT-Thrive-preserved MSCs demonstrated a ∼2.5-fold improvement in viable cell recovery compared to CS10, which failed to support recovery and expansion. XT-Thrive-preserved donor MSCs showed significantly higher cPDL at passages 8 FP (19.8 ± 0.4 vs. 15.4 ± 0.5, p < 0.001). CFU-F efficiency was also higher (∼23% vs. ∼15%). Furthermore, XT-Thrive-preserved MSCs exhibited enhanced osteogenic differentiation and increased secretion of FGF2 and HGF (1.8-fold and 2.1-fold increase, respectively), without compromising karyotype integrity, telomere length, or safety in vivo.

Conclusion: XT-Thrive provides superior pre-freeze stability, post-thaw recovery, expansion potential, and osteogenic functionality compared to CS10, while maintaining MSC identity and genomic stability. These results support XT-Thrive as a promising DMSO-free alternative for clinical-grade MSC biobanking and manufacturing.

Bone defect repair faces clinical challenges due to complex conditions caused by various factors such as trauma and aging. Traditional treatments have certain limitations, which seriously affect patients' prognosis. As the core organelle of cells, mitochondria regulate the activity of key cells including osteoblasts, osteoclasts, and bone marrow mesenchymal stem cells through functions such as oxidative phosphorylation (OXPHOS), production and scavenging of reactive oxygen species (ROS), regulation of Ca²⁺ concentration, modulation of cell death, and immune response, as well as dynamic processes including fusion, fission, mitophagy, and transport. Moreover, mitochondria interact synergistically with the neuro-vascular-muscle axis, participating deeply in bone defect repair. This article systematically reviews the mechanisms and research progress of mitochondria in bone defect repair, providing a theoretical basis for the development of novel mitochondria-targeted repair strategies and facilitating the research and development of efficient clinical treatment regimens. This will help to develop new treatment strategies for bone defects. These strategies will be more effective, safe and targeted for individual patients.

Objective: To analyze the changes in gait and muscle activation characteristics between persons with incomplete spinal cord injury (SCI) and persons without SCI with respect to age stratification, and to examine the differences between these populations.

Methods: Using the motion acquisition system and surface electromyography system, gait spatial-temporal, kinematic, dynamic parameters, and muscle activation characteristics were collected from 90 young, middle aged, and elderly persons with incomplete SCI, as well as an equivalent number of age-matched persons without SCI. The changes and differences in gait and muscle activation characteristics across age groups between these two populations were analyzed.

Results: Compared to the controls, persons with incomplete SCI of different age showed reduced walking ability, with notable differences in stance phase, swing phase, double stance, step length, stride length and velocity (P < 0.05). The swing angle of knee flexion showed an increasing trend with age, while the swing angle of ankle inversion and abduction showed a decreasing trend with age. The average center of pressure (COP) velocity increased with age among SCI persons and COP path length of young SCI persons was shorter than that in middle aged and elderly persons. Furthermore, the pressure peak and the ratio of pressure onset time also increased with age. The muscle activation parameters indicated that a positive correlation with age was observed for the average power frequency of anterior tibialis, while no regular change with age was noted for the gastrocnemius medialis.

Conclusion: Gait function and neuromuscular control strategies in persons with incomplete SCI are affected by age. The walking ability of young SCI persons was weaker compared to middle aged and elderly SCI persons with the same level, which may be related to differences in injury mechanism and age-specific expectations of walking ability. The changes in gait strategy and muscle activation patterns in persons with incomplete SCI provide an important basis for the development of age-specific rehabilitation intervention plans.

Hemophilia is an inherited bleeding disorder caused by mutations in the F8 or F9 gene, leading to a deficiency or dysfunction of coagulation factors VIII or IX. While current treatments, such as factor replacement, extended half-life factors, and gene therapy, have improved patient outcomes, they have limitations such as immunogenicity, transient transgene expression, and the requirement for high vector doses. Gene editing for hemophilia is an emerging approach that aims to provide a permanent cure by editing the mutated gene precisely or targeted integration of coagulation factor cDNA into the host genome for stable expression. This approach involves the use of programmable nucleases (CRISPR/Cas9, TALENs, ZFNs) that induce double-stranded DNA breaks at specific sites, allowing precise correction or targeted transgene integration. This review covers the various editing tools and strategies used for precise gene editing in hemophilia, including approaches such as HDR, NHEJ, base editing, prime editing, ex vivo gene editing in iPSCs, and recent LNP-based CRISPR delivery methods for precise editing.

Introduction: Bone tissue engineering requires scaffolds that mimic the native extracellular matrix and provide sustained delivery of osteoinductive factors. This study focuses on developing a multifunctional scaffold using a green electrospinning process to combine the biocompatibility of silk fibroin (SF) with a non-viral gene delivery system for sustained expression of Bone Morphogenetic Protein 2 (BMP2).

Methods: A green electrospinning technique, using an aqueous SF and polyethylene oxide (PEO) solution, was employed to fabricate nanofibrous scaffolds, eliminating the use of harsh organic solvents. Polyethylenimine (PEI) modified liposomes (Lipo^PEI) were used to encapsulate a BMP2-encoding plasmid (pDNA _Bmp2 ). These gene-loaded nanoparticles were incorporated into the SF-PEO nanofibers. The resulting scaffolds were characterized for morphology (SEM), structure (FTIR, XRD), and drug release kinetics. Biological performance was evaluated by assessing cell viability (MTT assay), cell attachment (SEM), gene transfection efficiency (confocal microscopy), and osteogenic differentiation (alkaline phosphatase (ALP) activity, Alizarin Red S staining) using bone marrow mesenchymal stem cells (BMSCs).

Results: Physicochemical characterization confirmed the successful formation of uniform pDNA_Bmp2@Lipo^PEI nanocomplexes with a particle size of approximately 266 nm and a positive surface charge of +16.9 mV. These nanocomplexes were homogeneously incorporated into smooth, bead-free SF-PEO nanofibers with average diameters ranging from 460 to 541 nm. The composite scaffold demonstrated a highly sustained release of pDNA_Bmp2 over 14 days. In vitro studies using rat bone marrow-derived mesenchymal stem cells (BMSCs) revealed that the scaffold possesses excellent biocompatibility, promoting robust cell adhesion, spreading, and proliferation. Furthermore, the gene-loaded scaffold successfully mediated the transfection of BMSCs, leading to significant upregulation of osteogenic markers, including alkaline phosphatase (ALP) activity and extensive calcium mineral deposition over 21 days.

Discussion: The novel composite scaffold combines the structural advantages of SF with a sustained BMP2 gene delivery system, showing remarkable potential to promote osteogenic differentiation. This work presents a promising, environmentally friendly, and effective platform for bone tissue engineering and regenerative medicine.