Bioengineering & Translational Medicine最新文献

Elevated levels of reactive oxygen species play an integral role in chronic inflammation. Current treatments for chronic inflammation often ignore reactive oxygen species and instead focus on symptom control or immunosuppression. However, by controlling reactive oxygen species in inflammatory environments, cyclic inflammation can be reduced. Combining reactive oxygen species scavenging delivery systems with stealth coatings can help avoid the innate immune system and enable targeted delivery to sites of inflammation without causing further oxidative stress. For this purpose, poly(propylene sulfide) nanoparticles were synthesized utilizing two different surfactants, Pluronic F-127 and sucrose monolaurate, adding stealth properties to the coatings of the reactive oxygen species scavenging nanoparticles. Characterization of the nanoparticles demonstrated the surfactant coatings did not affect the scavenging abilities nor the cytocompatibility of the materials. Degradation of the nanoparticles related to the sulfide groups and disulfide bond interactions with reactive oxygen species was also analyzed. Moreover, proinflammatory cytokine secretion from macrophages exposed to the nanoparticles was investigated to determine immune response evasion. Results obtained showed little to no activation of macrophages exposed to nanoparticle formulations in regard to MCP-1 cytokine release. However, there is room for improvement using glycerol-based coatings with regard to protecting cells from reactive oxygen species exposure and reducing macrophage activation in relation to IL-6 and TNF-alpha. Overall, the nanoparticles investigated have the capabilities to improve inflammatory disease treatments by not only targeting delivery of therapeutics to the site of inflammation, but also avoiding excess immune response recruitment due to incorporation of stealth coatings.

The increased preference amongst health care providers and patients for subcutaneous (SC) administration of biologics has necessitated the development of higher concentration formulations to maintain doses similar to intravenous (IV) products. These formulations possess manufacturing and administration challenges; particularly high concentration monoclonal antibody (mAb) formulations push the limit of injectability. Furthermore, patient-centric considerations, such as pain and fear of needles (trypanophobia), can lead to compliance deviations for long-term treatments. This study presents a set of evaluations of a novel computer-controlled, needle-free injector (NFI) design that can deliver 2.0 mL of a high viscosity (50 cP) mAb formulation into the SC space. Critical attributes such as antibody purity, aggregation, color, turbidity, and charge heterogeneity were evaluated before and after ejection and demonstrated minimal change compared to ejection from a 27-gauge needle and syringe (N&S). Furthermore, the device functionality was evaluated in a novel ex vivo pig skin model, demonstrating the ability to accurately deposit a 2.0 mL dose at an appropriate depth in the SC tissue, though requiring 8% greater fill volume than an N&S. An in vivo Yorkshire pig model was used to understand the pharmacokinetic (PK) profile of the NFI in comparison to a N&S. Clearance (CL), the observed peak concentration in serum (C_max), the time until C_max (T_max), area under the concentration-time curve extrapolated to infinity (AUC_inf), and half-life (t_1/2) were all within 1.2 fold and considered similar between the NFI and N&S. A non-significant difference in T_max was also observed. Bioavailability relative to IV administration was similar between the NFI (80.0%) and N&S (79.5%) groups. No concerning clinical observations and injection site reactions were observed. Ultimately, the NFI represents an advancement in SC delivery of high concentration mAb formulations with patient-centric design. This device could facilitate clinical and at-home use while complementing efforts to bridge IV and SC formulations.

Diabetic neuropathic pain (DNP) remains a significant challenge in diabetes care, and effective therapeutic strategies are urgently needed. This study introduces an innovative electrospinning-hydrogel composite, Fiber-SIN/Gel-LidC, designed for the controlled and synergistic release of Sinomenine (SIN) and Lidocaine (Lid). Bioinformatics and network pharmacology analyses identified MMP9 as a key player in DNP alleviation. The composite, composed of SIN-loaded fibers and Lid microcrystals, ensures sustained drug release over 7 days, demonstrating excellent biocompatibility. In vivo experiments on diabetic rats revealed significant improvements in thermal and mechanical pain thresholds, along with a reduction in sciatic nerve excitability. Additionally, the composite significantly attenuated neuroinflammation, neuronal apoptosis, and morphological damage. Mechanistic studies highlighted the neuroprotective effects of Fiber-SIN/Gel-LidC, particularly through the regulation of MMP9 and inhibition of sodium channels. These findings suggest that Fiber-SIN/Gel-LidC holds great potential as an innovative biomaterial-based approach for managing DNP, offering promising therapeutic prospects for diabetic neuropathy.

Stem cells from human exfoliated deciduous teeth (SHEDs) offer a promising alternative to bone marrow-derived mesenchymal stem cells (BMSCs) for bone tissue engineering due to their accessibility, high proliferative potential, and multipotency. In this study, we compared the osteogenic and angiogenic potential of two mesenchymal stem cells subpopulations, SHEDs and BMSCs, when co-cultured with human umbilical vein endothelial cells (HUVECs) into spheroids over a period of 28 days in porous pullulan/dextran scaffolds loaded with hydroxyapatite (HAp) particles as the sole osteoinductive cue. Spheroids were cultured under static and dynamic conditions, with the latter employing a perfusion flow bioreactor to enhance solute transport and oxygenation. Dynamic culture conditions significantly improved cell viability compared to static culture (85% vs. 54% at Day 28), maintained spheroid integrity, and promoted the expression of angiogenic markers, such as the cluster of differentiation 31 (CD31) and von Willebrand factor (vWF), which under static culture were largely confined to the spheroid periphery. Furthermore, alpha-smooth muscle actin/neural-glial-antigen 2 (αSMA/NG2) and CD31/NG2 colocalization reflected close spatial associations between SHEDs and HUVECs, suggesting a supportive perivascular interaction under dynamic culture. In the presence of HUVECs, we found that HAp particles alone were insufficient to induce robust osteogenic differentiation in SHEDs. Weak alkaline phosphatase activity, minimal osteopontin and osteocalcin expression, and incomplete mineralization were observed under both static and dynamic conditions. In contrast, BMSC/HUVEC spheroids exhibited robust osteogenic differentiation and consistent mineral deposition. These results show intrinsic differences in the behavior of SHEDs and BMSCs when co-cultured with endothelial cells; while BMSCs tend to favor osteogenesis, SHEDs appear to adopt a more perivascular or pericytic behavior.

Glioblastoma (GBM) is one of the most aggressive and rapidly progressing brain tumors, characterized by a low survival rate, in part due to insufficient diagnostic tools. Computed tomography (CT), although widely available, is limited in use for GBM diagnosis by the suboptimal performance of current clinically approved contrast agents. This study focuses on the development of gold nanoparticle (AuNP)-loaded polymersomes (AuPs) to improve the detection of GBM. We synthesized polyethylene glycol-b-polylactic acid (PEG-b-PLA) polymersomes with high AuNP loading. Increasing the concentrations of AuNPs in polymersomes resulted in enhanced contrast using clinical CT. Furthermore, AuPs bound to cell-penetrating peptide TAT were cytocompatible with U87-MG GBM cells at concentrations up to 100 mg/mL. Uptake studies using both fluorescence microscopy and flow cytometry confirmed the internalization of AuPs into GBM cells, with a direct correlation between AuP concentration and uptake efficiency. MicroCT imaging also confirmed a similar trend; >300% enhanced contrast compared to PBS controls was observed with increasing concentrations of AuPs and was maintained in vivo at 337–863 HU. Overall, these results demonstrate that a polymersome-based system for AuNPs enhances CT image contrast, suggesting that this approach could be feasible for improving GBM detection via CT.

Metastasis is the principal cause of mortality in breast cancer, but therapies specifically targeting metastatic mechanisms are scarce. In triple-negative breast cancer (TNBC), hypoxia within the tumor microenvironment (TME) promotes endothelial dysfunction, increasing vascular permeability and facilitating cancer cell intravasation. This study presents a microfluidic-based idealized microvascular on-chip (iMVoC) model utilizing human umbilical vein endothelial cells and TNBC cells (SUM159PTX) to model a hypoxic TME. This model mimicked dynamic flow perfusion, promoting endothelial alignment along the flow direction, while supporting 3D tumor structures exhibiting varying oxygen levels in the tissue compartment. The iMVoC model enabled cell–cell interactions and the exchange of media and nutrients between compartments. Hypoxia was confirmed by increased nuclear translocation of hypoxia inducible factors (HIF)-1α and HIF-2α in TNBC cells, indicating hypoxia-based signaling. Hypoxia-induced endothelial cell (EC) inflammation was validated through elevated permeability, upregulation of adhesion molecules, and increased reactive oxygen species (ROS) production, suggesting activation of the HIF-ROS pathway. Enhanced tumor cell intravasation was observed across inflamed endothelium, and cytokine profiling further confirmed EC activation through inflammatory signaling. Application of the protein kinase C delta (PKCδ) inhibitor (PKCδ-TAT) significantly mitigated these effects, shifting HIF localization from the nucleus to the cytoplasm, reducing ROS production, downregulating inflammatory cytokines, and lowering TNBC intravasation. These findings demonstrate PKCδ as a key mediator linking hypoxia to EC dysfunction and tumor dissemination. Protecting EC barrier integrity emerges as a promising strategy to mitigate hypoxia-driven TNBC metastasis, with the iMVoC platform offering a valuable tool for testing anti-cancer therapeutics or drug combinations involving PKCδ-TAT.

Osteoarthritis (OA) is a prevalent chronic degenerative joint disease with no known treatment for reversing its progression. However, recent studies have shown promising results for nano-sized extracellular vesicles derived from preconditioned synovial mesenchymal stem cells (SMSCs) in treating various diseases, including OA. Glucocorticoids (GCs) possess potent anti-inflammatory properties, but their long-term use is limited due to potential adverse reactions. Building on previous research, this study aimed to investigate the therapeutic potential of extracellular vesicles secreted from GCs-pretreated SMSCs (GCs-EVs) in exerting antiarthritic effects. The results demonstrated that GCs-EVs effectively inhibited cartilage degeneration and osteophyte formation in the OA mouse model by suppressing the release of inflammatory cytokines from synovial macrophages. This effect was attributed to the high expression of miR-212-5p in GCs-EVs, which specifically inhibited the expression of methyltransferase-like 3 (Mettl3). Consequently, the mRNA N6-methyladenosine (m⁶A) level of nod-like receptor pyrin domain 3 inflammasome (NLRP3) in macrophages was reduced, leading to decreased NLRP3 inflammasome activity and increased antiarthritic effects. Furthermore, in the co-culture system, GCs-EVs enhanced chondrocyte proliferation and migration while inhibiting chondrocyte apoptosis by suppressing the secretion of inflammatory factors by macrophages.

Preterm brain injury affects both white and gray matter, including altered cortical development and gyrification, with associated neurodevelopmental sequelae such as cerebral palsy and learning deficits. The preterm brain also displays regionally heterogeneous responses to both injury and treatment, suggesting that drug combinations may be needed to provide global neuroprotection. We developed an extremely preterm-equivalent organotypic whole hemisphere (OWH) slice culture mild injury model using the gyrencephalic ferret brain to probe treatment mechanisms of promising therapeutic agents and their combination. Regional and global responses to injury and treatment were assessed by cell death quantification, machine learning-augmented morphological microglia assessments, and digital transcriptomics. Using two promising therapeutic agents, azithromycin (Az) and erythropoietin (Epo), we show minimal neuroprotection by either therapy alone, but evidence of synergistic neuroprotection by Az*Epo both globally and regionally. This effect of Az*Epo involved augmentation of transcriptomic responses to injury related to neurogenesis and neuroplasticity and downregulation of transcripts involved in cytokine production, inflammation, and cell death. With the increasing need to develop therapies for extremely preterm brain injury, the ferret OWH slice culture model provides a high-throughput platform to examine combinations of therapeutics as part of a preclinical therapeutic pipeline.