Bioengineering & Translational Medicine

Human salivary stem/progenitor cell (hS/PC)-loaded hyaluronic acid (HA)-based hydrogels, termed 3D-salivary tissue constructs (3D-ST), hold great promise for restoring salivary gland function post-radiation injury. Here, we developed a next-generation 3D-ST using heparin-modified HA and bioactive peptide-modified hydrogels. This new formulation enables controlled pre-loading and localized presentation of heparin-binding growth factors prior to surgical implantation, providing opportunities to enhance in vivo hS/PC bioactivity. To model clinically relevant radiation injury, we established an athymic rat model subjected to computed tomography (CT)-guided fractionated radiation, resulting in hallmark features of radiation-induced salivary dysfunction. Over 60-days post-irradiation, glands exhibited progressive loss of acini, increased fibrosis, and disruption of endothelial, neuronal, and myoepithelial compartments. Within this injured environment, a surgical pocket was created to precisely implant 3D-STs to assess graft performance. Fluorescent labeling of the 3D-STs enabled longitudinal tracking post-implantation. Over 14 days, implanted 3D-STs remained structurally stable within irradiated glands, and hS/PCs remained viable without evidence of local inflammatory responses. Compared to non-injured glands, the irradiated microenvironment suppressed hS/PC proliferation and phenotype, indicating alterations in the irradiated local tissue negatively impact hS/PC bioactivity. In addition, host neurovascular migration into the 3D-ST was majorly restricted in irradiated glands, providing new opportunities to enhance biointegration. Overall, this work establishes a reproducible preclinical framework for assessing hydrogel biocompatibility and stability, cell bioactivity, and host-graft biointegration prior to scale up into preclinical large animal models. This study has successfully established a tractable approach for improving 3D-ST formulations to enhance hS/PC expansion, differentiation, and biointegration following implantation into radiation-injured beds.

The limiting step in immune-active drug development is increasingly not candidate generation but testing whether a candidate therapy is effective in a system that preserves tissue architecture, vascular exposure, multicellular interaction, and repeated pharmacodynamic sampling without patient exposure. We developed an acellular normothermic machine-perfusion platform for intact porcine spleen designed as a translational immune-organ assay. Across independent acellular perfusions, the circuit maintained physiologic parameters, preserved red- and white-pulp histology, and yielded viable effluent cells suitable for serial flow cytometry and multiomics. High-dose methylprednisolone was used as a clinically familiar perturbation to determine whether the platform could resolve steroid immunosuppression at mechanistically distinct levels. Effluent RNA-seq identified canonical glucocorticoid-responsive transcriptional programs, including DUSP1, FKBP5, PER1, DDIT4, SGK1, KLF9, ANXA1, NF-{kappa}B feedback regulators, and JAK/STAT suppressor pathways. SOCS3 was a prominent early signal in the perfusion transcriptome and was validated orthogonally at the protein level in prednisone-treated, CD3/CD28-activated primary murine splenocytes, strengthening its role as a candidate pharmacodynamic marker. In parallel, data independent acquisition (DIA) proteomics of effluent cell pellets nominated a non-transcriptional protein-level response: a Sus scrofa LGALS13-annotated, CLC/Galectin-10-like galectin detected despite absence of the corresponding effluent-cell transcript. Because this porcine LGALS13-annotated protein group is treated here as an orthologous CLC/Galectin-10-like signal rather than as canonical human placental Galectin-13/PP13, we tested recombinant human Galectin-10 in vitro. Human Galectin-10 induced marked apoptosis of CD3/CD28-stimulated Jurkat cells, prioritizing this axis for future mechanistic testing without proving causality in the perfused spleen. These data establish acellular spleen perfusion as a serial multiomic platform for translational immunopharmacology and motivate deployment with otherwise-discarded human donor spleens. One sentence summaryAn acellular intact-spleen perfusion platform enables serial cellular, transcriptomic, proteomic, and functional pharmacodynamic sampling that identifies steroid-responsive transcriptional programs, validates SOCS3 protein induction, and nominates a CLC/Galectin-10-like non-transcriptional immunosuppressive axis for translation to discarded human donor spleens.

Intratumoral (i.t.) delivery of nanoparticles (NPs) is widely used to achieve high local NP concentrations. However, the temporal fate of i.t.-injected NPs remains poorly understood. We present a quantitative approach using whole-body magnetic particle imaging (MPI) to track magnetic NPs (MNPs) following i.t. injection. Using fiducial-calibrated imaging, we quantified MNP mass over time in subcutaneous 4T1 breast tumors. Longitudinal imaging revealed progressive loss of i.t. MNP content and heterogeneous systemic redistribution across animals despite standardized delivery conditions. Ex vivo MPI confirmed off-target accumulation primarily in the liver and spleen, consistent with reticuloendothelial clearance pathways. Histological analysis demonstrated spatially heterogeneous i.t. MNP deposition, potentially associated with local vascular features and tumor microenvironmental heterogeneity that may influence i.t. MNP retention or MNP clearance from the tumor. These findings highlight the importance of quantitative longitudinal whole-body MPI for understanding the fate of MNPs for informing localized nanotherapy.

Cyclophosphamide (CP) is a widely used alkylating agent whose cytotoxic activity depends on hepatic CYP450-mediated bioactivation. While CP-associated neurotoxicity and cognitive impairment are recognized clinically, the mechanisms of secondary organ damage through metabolic cross-talk remain poorly understood due to limitations of conventional monoculture models. Here we employ a multi-organ microphysiological system (MPS) connecting stem cell derived liver and CNS organoids via microfluidic channels to model inter-organ drug metabolism and secondary toxicity. Liver organoids were treated with CP (0-200 {micro}M) for 48 hours, and connected CNS organoids were assessed for secondary damage by confocal Z-stack imaging of DNA damage ({gamma}H2AX), neuronal identity (NeuN), and nuclear content (DAPI). We observe dose-dependent reduction in NeuN expression and {gamma}H2AX signal in connected CNS organoids, consistent with neurotoxic metabolite transfer from liver. Critically, CNS-to-CNS control connections show no comparable damage at equivalent CP concentrations, confirming that hepatic metabolism is required for CNS toxicity. These findings validate the MPS platform for modelling multi-organ drug toxicity and provide direct evidence that liver-derived CP metabolites drive secondary neurotoxicity through inter-organ metabolic communication.

Extracellular vesicles (EVs) are versatile therapeutic candidates due to biological roles in intercellular communication and amenability to bioengineering. Compared with lipid nanoparticles (LNPs), native or surface-modified EVs may have favorable immunogenicity and biodistribution profiles. However, when administered intravenously (IV), EVs are rapidly cleared and accumulate mostly in the liver and spleen. With the goal of modifying EV biodistribution, we engineered EVs to display the human endogenous retrovirus (HERV) envelope glycoprotein Syncytin-1, an SLC1A5-binding fusogenic viral protein essential for syncytiotrophoblast formation in pregnancy. Here, we comprehensively characterize engineered Syncytin-1+ EVs, examine their interactions with cells in vitro, and assay biodistribution, immunogenicity, and pharmacokinetics ex vivo and in vivo in non-human primates. IV-administered Syncytin-1+ EVs are well tolerated, persist in the blood stream, and have altered organ biodistribution compared with unmodified EVs, suggesting therapeutic potential of Syncytin-1+ EVs at specific sites.

Fv-HSP72 is a rapid cell-penetrating human heat shock protein for the treatment of traumatic organ injuries. We have shown this re-engineered protein (HSP72) is capable of crossing the blood brain barrier (BBB) of rats suffering a controlled cortical impact (CCI) and remains in brain tissue for up to 12 hours; long after clearance from the cortex of uninjured rats. Peptide sequences unique to Fv-HSP72 allow for its differential detection from endogenous HSP72. Male Sprague-Dawley rats were divided into 10 groups of n=10 with those animals receiving a CCI subjected to a unilateral cortical contusion simulating a moderate to severe brain injury using an electronically controlled pneumatic impact device. Control groups were either uninjured (Sham), injured (TBI Only), or injured and given buffer (TBI+Vehicle). Rats treated with one of three Fv-HSP72 variants were dosed at 10 or 30mg/kg 15m post-impact, then sacrificed 48 hours later. Cortical tissues were extracted from the ipsilateral and contralateral hemispheres for biomarker analysis. Here we report results of our drug inhibiting neurodegeneration based on five biomarkers (NF-L, pNF-H, pTau [T181, T231, S396]). These results were statistically significant, especially for one of the Fv-HSP72 variants, when comparing differences both between treatment groups and within groups (i.e. when comparing ipsi-vs. contralateral hemispheres). Significant inhibition of oxidative stress (3-NT) and inflammatory (IL-6) biomarkers were also observed (both p<0.0001). With similar results obtained for a blast injury model being published elsewhere, the analyses suggest Fv-HSP72 is neuroprotective following a direct impact brain injury. One sentence summaryThis study describes the effectiveness of a biologic agent, Fv-HSP72, in significantly inhibiting neuronal tissue damage in the brain when administered after a direct cortical impact.

Background and ObjectivesCardiovascular cells differentiated from human induced pluripotent stem cells (iPSCs), including cardiomyocytes, are valuable for evaluating human cardiac pharmacology and toxicity. Early assessment of cardiotoxicity, especially for novel drugs like anticancer agents, is essential for improving drug development efficiency and reducing costs. This study aimed to develop a highly sensitive bioassay system capable of evaluating the physiological function of human cardiac tissue in vitro. MethodsHuman iPSCs were differentiated into cardiovascular cell types (cardiomyocytes, vascular endothelial cells, and vascular mural cells) and assembled into a cardiac tissue model on aligned fiber device. This tissue was cultured dynamically to induce the formation of vascular network-like structure. By combining the fiber device with our previously developed heart-on-a-chip microdevice (HMD), we created a new model of HMD (Aligned Fiber-based HMD; AF-HMD) with improved throughput and stability. Pulsatile force changes induced by drug exposure were quantified by tracking the displacement of fluorescent microbeads within the microchannels. ResultsAF-HMD demonstrated functional responses to known cardiac agonists and toxicants, such as doxorubicin. The device also replicated clinically relevant cardiotoxic events, including the synergistic effects of trastuzumab and doxorubicin, showing marked reductions in contractile force and beat rate, mirroring clinical observations. ConclusionsThe AF-HMD system provides a sensitive and reproducible platform for evaluating cardiotoxicity in drug development. It offers a promising tool for preclinical screening, with potential applications in personalized medicine and predicting cardiotoxic risk in cancer therapy.

Cardiac rhythm is a critical clinical indicator for cardiac arrhythmias and adverse events during drug toxicity studies. In vivo, cardiomyocyte responses to pharmacological agents occur within minutes and are strongly influenced by dynamic drug delivery through blood flow. However, conventional 2D and 3D static culture systems fail to replicate these fluid flow kinetics, limiting their physiological relevance for assessing beat rate responses. Here, we present Mera, an advanced microphysiological system (MPS) developed by Hooke Bio, designed for high-throughput, long-term culture and functional analysis of 3D cardiac spheroids composed of human induced pluripotent stem cell-derived cardiomyocytes and cardiac fibroblasts. Mera enables dynamic perfusion, allowing investigation of cardiomyocyte beat rates under physiologically relevant flow conditions. The platform supports up to 640 spheroids per run and integrates automated imaging, fluid handling, and user-friendly software, operating under controlled physiological conditions (37{degrees}C, 5% CO2). Flow rates are tunable between 0 and 12.5 mL/min to mimic in vivo environments. Pharmacological testing with verapamil, isoproterenol, calcium chloride, and propranolol demonstrated real-time, reversible modulation of beat rate under flow, including recovery following drug-induced suppression. System variability was comparable to a temperature-controlled reference platform, supporting robust statistical analysis. Dose-response studies yielded IC values consistent with literature, confirming physiological relevance. Collectively, these results demonstrate that Mera provides a reproducible, scalable, and human-relevant platform for cardiac drug testing. By enabling dynamic drug exposure and automated analysis, Mera represents a powerful new approach methodology (NAM) for improving the predictive assessment of cardiac safety and beat-rate modulation drug responses.

Pulmonary delivery of lipid nanoparticles (LNPs) remains an area of significant interest, given the broad range of genetic disorders that could be addressed through localized administration of therapeutic nucleic acids to the lung. In this study, we investigated how incorporation of the clinically used lung surfactant cocktail Poractant alfa affects the in vitro and in vivo transfection performance of mRNA-loaded LNPs. The resulting lung surfactant-enhanced LNPs (Surf-LNPs) exhibited substantial improvements in particle assembly, yielding an order of magnitude higher particle concentration at equivalent input conditions compared to conventional (Onpattro-like) LNP formulations. In vitro, Surf-LNPs demonstrated several-fold increases in mRNA transfection efficiency and protein expression while maintaining excellent cytocompatibility. These enhancements are attributed to an elevated apparent pKa and the surface-active properties of surfactant protein B (SP-B), which promote more rapid and efficient endosomal escape relative to conventional LNPs. In vivo evaluation following intranasal administration further revealed enhanced mCherry expression in the lungs of mice treated with Surf-LNPs compared to conventional LNPs. Ultimately, these findings establish lung surfactant incorporation as a simple yet powerful formulation strategy to improve pulmonary gene delivery using LNPs, with the potential to significantly advance the translation of inhaled nucleic acid therapeutics.

Tracking gastrointestinal (GI) transit in preclinical models is essential for assessing gut motility and drug delivery. Current preclinical methods rely on end-to-end transit measurements or emptying studies that require terminal endpoints and organ explanation. Clinically, radiopaque "Sitz" markers are administered orally and their position in the GI tract is assessed through radiography. Sitz markers have been in use since 1969 and are typically mass-produced using industrial molding or extrusion, resulting in a single, fixed geometry with limited tunability. We present a stereolithography (SLA)-based method to fabricate customizable radiopaque markers using additive manufacturing with a barium sulfate (BaSO4)-doped resin. We demonstrate precise control over marker geometry, a key advantage over existing markers. Furthermore, we apply this method in vivo, tracking markers in a live rat model from ingestion to excretion using serial CT imaging. We systematically investigate how changes in marker geometry impact GI residency and transit time. Our results show that 3D printed markers provide a flexible and tunable platform for radiopaque marker fabrication and enable investigation of the fundamental relationship between a markers physical properties and its performance in a dynamic biological environment. This work establishes a novel, tunable platform for GI motility evaluation and drug delivery studies.

Controlled release systems for subcutaneous peptide delivery often exhibit a pronounced initial burst release followed by inadequate maintenance of therapeutic exposure, limiting depot lifetime and increasing pharmacokinetic variability. Here, we engineer a dynamic, injectable hydrogel depot technology for months-long delivery of lipidated peptides. Using semaglutide as a model, we establish a modular formulation framework integrating: (i) formulation-driven tuning of depot mechanics to control release kinetics, (ii) cargo complexation strategies leveraging hydrophobic and multivalent ion-mediated interactions, and (iii) oxidative stabilization through sacrificial antioxidant excipients. We evaluated depot performance by rheology, in vitro cargo release, and in vivo pharmacokinetic and pharmacodynamic studies in rodents. Optimized formulations sustained semaglutide exposure for over six weeks from a single administration with two-fold reduction in peak-to-trough exposure and comparable total bioavailability relative to daily dosing, resulting in improved glucose control, weight regulation, and preservation of pancreatic islet content. These results suggest potential for quarterly dosing in humans. Together, this work establishes integrated and generalizable structure-property-performance relationships that account for cargo-matrix and cargo-excipient interactions across burst, diffusion, and erosion regimes to inform a practical formulation framework for engineering long-acting depots for sustained peptide delivery.

This study focuses on the development of 3D culture model dedicated to liquid cancers drug screening. The challenge addressed was to effectively retain non adherent small cells within a 3D-scaffold with tailorable mechanical properties, while proposing a fast and effective tool for drug screening. To that aim, we developed a macroporous alginate-chitosan polyelectrolyte complex (PEC) scaffold combined with a low-viscosity alginate (LVA) cell seeding solution. We hypothesized that LVA could undergo in situ pore gelation via calcium ions retained from the PEC fabrication process, enabling effective retention and homogeneous cell distribution, leading to an improved platform for drug screening and personalized medicine. First, we evaluated scaffold suitability for LVA infiltration and gelation. Microtomography revealed a highly porous architecture (98%) enabling LVA homogeneous penetration and complete gelation within 30 min, as confirmed by SEM, microscopy, rheology, and micro-rheology. Next, we assessed cell retention and biocompatibility using primary human chronic lymphocytic leukemia (CLL) cells. LVA-assisted seeding increased cell density 2.6-fold compared to medium alone, with homogeneous distribution, >80% viability over 7 days, and preserved differentiation into nurse-like cells. Finally, we demonstrated a proof of concept for drug screening. The Alginate-PEC scaffold (A-PEC scaffold) supported both qualitative live/dead imaging and rapid quantitative viability measurement with the Alamar Blue assay. Drug responses reproduced microenvironment-dependent protection effects observed in vivo. This integrated scaffold and seeding method provides a promising 3D platform for in vitro liquid cancer studies and drug screening on patient-derived hematological cancer cells. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=67 SRC="FIGDIR/small/722037v1_ufig1.gif" ALT="Figure 1"> View larger version (38K): org.highwire.dtl.DTLVardef@9b71d4org.highwire.dtl.DTLVardef@14e1dd0org.highwire.dtl.DTLVardef@1876a56org.highwire.dtl.DTLVardef@15656bc_HPS_FORMAT_FIGEXP M_FIG C_FIG

Over the past decade, the integration of microgel-based granular hydrogels in biomedical technologies has experienced substantial growth due to the numerous benefits microgels offer. However, the inability to easily adopt uniform microgel fabrication workflows at scale constitutes a major bottleneck, or in some cases, a barrier-to-entry that stunts further growth of the field. The gold-standard technique for emulsion-based microgel production is through microfluidic droplet-generating devices that produce liquid gel precursor droplets that gel post-production. However, traditional microfluidic workflows often require multiple independent flows and controlled pressure sources, along with a steep learning curve in using microfluidics to achieve uniform droplet sizes reproducibly and repeatedly. This difficulty in adopting microgel fabrication is further compounded by low throughput and the extensive flow rate calibration required when switching to new formulations (e.g., material type, droplet size). In this work, we present a step-emulsion system that bridges the gap by providing a robust and simple setup. We experimentally characterize and evaluate how flow and outlet channel dimension contribute to the generation of uniform droplet populations at specific sizes. With our large dataset consisting of various outlet channel dimensions, we evaluated outlet channel geometrical impacts (height, width, cross-sectional area, aspect-ratio, etc.) on gel precursor droplet size and generation throughput. We demonstrate robust, highly compatible, and repeatably uniform droplet generation from various gel precursor polymer backbones, users with varying microfluidics experience, and a wide viscosity range, including alginate solutions with 650 times the viscosity of water. Furthermore, we confirmed consistent gel precursor droplet generation outcomes driven by a constant flow source (syringe pump) and by direct manual injection as a simple and highly adoptable option for the generation of gel precursor droplets. This platform is ideal for researchers seeking rapid and easy microgel fabrication, regardless of microfluidics experience.

IntroductionCancer progression is driven not only by tumor cells but also by interactions between the extracellular matrix (ECM), stromal cells, and immune cells within the tumor microenvironment (TME). Cancer-associated fibroblasts (CAFs) are major drivers of ECM remodeling, assembling ECM with aberrant organization. Extra domain A fibronectin (EDA-FN), a cellular FN containing an extra type III domain, is upregulated in the TME. EDA-FN regulates cellular behavior and has been associated with poor patient prognosis. Macrophages are among the most abundant immune cells within the TME, where they contribute to TME remodeling and inflammation to promote cancer cell invasion and metastasis. However, how tumor-associated matrix-specific cues regulate macrophage behavior remains largely understudied. PurposeHere, we developed a fibroblast-derived matrix platform that captures the structural imprint of tumor-associated EDA-enriched matrices and investigated how matrix-specific cues regulate macrophage behavior in the absence of ongoing soluble factor cues. MethodHuman mammary fibroblasts (HMFs) preconditioned in incubated low-serum media (lNC, or control) and MDA-MB231 metastatic breast cancer cell-conditioned media (mTCM) were cultured on polyacrylamide gels of 2 kPa and 20 kPa, respectively, followed by decellularization. Matrix organization, including fiber alignment, width, and intrafibrillar spacing, was quantified from confocal images. Decellularized EDA-FN-enriched matrices were subsequently reseeded with macrophages to assess macrophage morphology, phenotype, and matrix interactions. ResultsThe combined effects of tumor-derived soluble factors and pathological stiffness induced a CAF-like phenotype in HMFs, accompanied by cytoskeletal reorganization and microarchitectural alterations of EDA-FN-enriched matrices. Tumor-associated matrices exhibited increased alignment, narrower fiber width, and enlarged intrafibrillar spacing compared to control matrices. These aberrant, tumor-associated matrix-derived features were associated with altered macrophage behavior, including heterogeneous morphology, enhanced localized EDA-FN matrix loss beneath the cell body, and a hybrid phenotype with a shift toward a CD206-dominant profile. ConclusionsThese findings demonstrate the feasibility of obtaining EDA-FN-enriched matrices to isolate matrix-specific cues for investigating macrophage-ECM interactions. Furthermore, this platform can be leveraged to identify matrix-targeting therapeutic approaches for modulating macrophage function within the TME.

Tissue engineered constructs are increasingly used for both modeling organs and disease in vitro as well as for therapeutic intervention. In addition to collagen, these constructs commonly include native extracellular matrix proteins (ECM), such as fibronectin and laminin. Given the critical role of inflammatory pathways in disease and in response to implanted materials, it is important to understand the role these proteins play in regulating the inflammatory environment. Fibronectin and laminin influence neutrophil function and endothelial activation in 2D, but their regulation of the inflammatory environment in 3D engineered constructs is not clear. For this study, we used an inflammation-on-a-chip device that includes a model blood vessel surrounded by a collagen I hydrogel with fibronectin and/or laminin. We investigated the additive effects of both proteins and a range of concentrations for each protein to determine concentration dependence. Both fibronectin and laminin have concertation dependent effects on neutrophils and the endothelium. High concentrations (50 {micro}g/mL) of fibronectin reduced neutrophil migration, while 20 {micro}g/mL laminin reduced neutrophil extravasation and migration, potentially due to lower ICAM-1 expression by the endothelium. Interestingly, 50 {micro}g/mL of laminin significantly disrupted endothelial vessel formation and reduced ICAM-1 and VE-cadherin expression, likely due to significant changes in the collagen architecture. The inclusion of fibronectin and laminin, even at physiological levels, results in significant effects on neutrophil behavior, endothelial vessel formation, and collagen architecture. These proteins impact the inflammatory environment and thus need to be considered when modeling diseases and designing therapeutics, especially when neutrophils or an endothelium are involved. Translational Impact StatementThis work uses an inflammation-on-a-chip device to study how fibronectin and laminin impact neutrophil behavior and vascular inflammation as these proteins are commonly used in engineered constructs. We found that fibronectin impairs neutrophil migration, while laminin decreases neutrophil extravasation and migration and at higher concentrations also prevents endothelial vessel formation. Therefore, researchers should be aware that these proteins will alter the inflammatory environment when including them in engineered constructs.

Atopic dermatitis (AD) is a highly prevalent, relapse-remitting, inflammatory skin disease, the hallmark symptom of which is chronic itch. Mechanisms underlying AD itch are multifactorial, involving various cells, receptors, and mediators. Developing a physiologically relevant, human model system for AD itch research and drug development is crucial. To this end, human induced pluripotent stem cell-derived sensory neurons (iPSCSNs) were cultured with human primary keratinocytes to form deconstructed skin models. Using Ca2+-imaging in a direct contact, 2.5D co-culturing format, which mimics natural skin innervation and permits both paracrine exchange and juxtacrine signaling, iPSCSNs exhibited functional TRPA1 responses not seen in monotypic iPSCSN cultures or in iPSCSNs conditioned with keratinocyte medium. Different AD-associated cytokines were used to stimulate the co-culture systems to mimic an inflamed lesional skin environment, whereby TNF was found to increase iPSCSN chemosensitivity. Finally, both TRPA1 and JAK1/2 inhibition reduced iPSCSN responses to pruritogens (TSLP, IL-31), thus supporting TRPA1 as a therapeutic target for AD itch in humans. This study demonstrates that human deconstructed skin models can be a useful tool in AD and broader pruritus research. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=181 SRC="FIGDIR/small/724000v1_ufig1.gif" ALT="Figure 1"> View larger version (35K): org.highwire.dtl.DTLVardef@11c0c9borg.highwire.dtl.DTLVardef@7fa518org.highwire.dtl.DTLVardef@2fe7a2org.highwire.dtl.DTLVardef@1105fa7_HPS_FORMAT_FIGEXP M_FIG C_FIG

Curcumin is a naturally occurring polyphenol that demonstrates considerable anti-cancer activity, however the aqueous insolubility, rapid metabolism and relatively low bioavailability are limiting to its clinical application. As such, a curcumin-magnesium (Cur-Mg) coordination complex was synthesized and subsequently encapsulated within DNA hydrogels (Cur-Mg-Hgel). The Cur-Mg complex was fully characterized using UV-Vis spectroscopy, FTIR and X-ray diffraction (XRD). UV-Vis, FTIR and XRD all support the formation of a coordination complex and suggest a decreased level of crystallinity compared to free curcumin. DNA hydrogels were formed and characterized using atomic force microscopy, rheology and swelling kinetic studies. In vitro cytotoxicity studies utilizing an MTT assay demonstrate dose dependent inhibition of HeLa cell proliferation and a slightly better retention of RPE-1 viability at low concentrations (suggesting some difference in sensitivity) though significant cell death is seen at higher concentrations and both cells. Intracellular production of ROS was measured using the DCFH-DA assay and is seen to increase when HeLa cells are treated with Cur-Mg-Hgel in comparison to un-treated controls. Annexin V/PI staining demonstrates primarily late or early apoptotic activity with minimal necrosis following treatment with Cur-Mg-Hgel. The evidence presented strongly supports the notion that Cur-Mg-Hgel is a ROS-modulating, pro-apoptotic Hydrogel suitable for cancer treatment. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=102 SRC="FIGDIR/small/724072v1_ufig1.gif" ALT="Figure 1"> View larger version (42K): org.highwire.dtl.DTLVardef@18727aeorg.highwire.dtl.DTLVardef@3e20adorg.highwire.dtl.DTLVardef@d3703eorg.highwire.dtl.DTLVardef@16e260e_HPS_FORMAT_FIGEXP M_FIG C_FIG

Osteosarcoma (OS) is the most prevalent primary bone malignancy in children and adolescents; however, therapeutic outcomes remain suboptimal due to tumor heterogeneity, chemoresistance, and inadequate immune activation. Doxorubicin (Dox), the standard therapy that induces immunogenic cell death, has its efficacy compromised by the immunosuppressive tumor microenvironment (TME). While interleukin-12 (IL-12) can activate and recruit various immune cells, making it an attractive combination partner, its systemic delivery is severely limited by dose-limiting toxicity. We have previously reported that intravenous injection of A3 collagen binding domain (CBD) of von Willebrand Factor preferentially accumulates into the TME of various tumor models enriched in collagen I and III. Furthermore, CBD-fused IL-12 (CBD-IL-12) demonstrated superior therapeutic effects against various cancer models compared to unmodified IL-12 due to its collagen-targeted delivery and the resulting tumor-localized inflammation. Given that the OS TME also exhibits higher collagen I and III expression compared to normal bone, we hypothesized that a CBD-IL-12 fusion protein could showcase potent anti-tumor efficacy in OS via tumor-specific accumulation. Here, we demonstrated that CBD-IL-12 exhibited 4-fold enhanced tumor accumulation compared to unmodified IL-12 and increased cytotoxic T cell infiltration by 2.2-fold within the immune-cold microenvironment in a mouse model of OS. The combination of CBD-IL-12 with Dox significantly prolonged median survival in two independent murine OS models. This coordinated approach utilizing Dox coupled with precision-targeted IL-12 immunotherapy represents a clinically translatable strategy that overcomes the inherent limitations of single-agent treatments for OS. HighlightO_LICollagen-targeted IL-12 increases tumor accumulation in osteosarcoma. C_LIO_LIThe collagen-targeted IL-12 synergizes with doxorubicin in osteosarcoma models. C_LIO_LICombination therapy enhances T cell differentiation and activates innate immunity. C_LI

Focal injuries to articular cartilage in load-bearing joints fail to heal and often progress to degeneration, underscoring the need for repair strategies that result in restored cartilage structure and function rather than fibrocartilage formation. Granular extracellular matrix (gECM) hydrogels, flowable grafts composed of densely-packed matrix particles, offer a promising approach but lack long-term functional validation in large-animal models. Here, we developed a flowable gECM hydrogel composed of decellularized cartilage microparticles incorporated within a thiol-functionalized hyaluronan matrix. Proteomic analysis confirmed enrichment of cartilage-specific gECM matrisome components. When implanted into critical-sized femoral condyle defects in a goat model and evaluated 12 months post-implantation, both gECM hydrogel and microdrilling (surgical controls) achieved >80% defect filling. However, in contrast to microdrilling, gECM repair tissue exhibited surface tribological (friction, adhesion) and compressive mechanical properties comparable to native cartilage, with a similar proteoglycan-to-collagen ratio, enrichment of type II collagen, minimal type I collagen (typical of a fibrous scar), improved quantitative MRI metrics, and evidence of lateral cartilage integration and subchondral bone remodeling. Together, these findings demonstrate that a flowable gECM hydrogel supports integrative, cartilage-like repair in a load-bearing joint, supporting advancement of this approach toward clinical translation. One Sentence SummaryA granular ECM hydrogel implanted in a goat condyle provided a robust repair, filling the defect tissue with integrated, hyaline-like cartilage at 12 months.

Ancestry-associated immune differences influence fibrosis risk, however, how fibrosis-associated pathways vary across individuals remains poorly understood. Fibroblasts are a main cell type involved in fibrosis. The fibroblast response is shaped by cytokine signaling and macrophage activation. The extent to which these pathways vary across individuals, and how ancestry-associated immune differences influence fibrosis risk, remains poorly understood. Here, a poly(ethylene glycol) (PEG)-based hydrogel microphysiological system was leveraged to model fibroblast-macrophage interactions following oxidative stress and to integrate donor-specific immune signals using matched macrophages and serum. Individuals of self-reported African ancestry exhibited higher monocyte expression of CCL4, lower monocyte expression of OXER1, and increased serum IL-10, compared to individuals of European ancestry. Within the hydrogel, oxidative stress reduced fibroblast prevalence while inducing Ki67 and p16. Exogenous TGF-{beta}1 increased fibroblast prevalence and collagen 3 production but did not independently increase -SMA. Incorporating donor-specific macrophages and serum revealed that cultures from individuals of European ancestry demonstrated higher fibroblast -SMA and p16 expression. Pharmacologic inhibition of IL-10 further increased -SMA, particularly in African ancestry-derived cultures, identifying IL-10 as a key protective signal limiting fibroblast activation. This hydrogel system provides a platform for dissecting inter-individual immune variation and identifying mechanisms underlying ancestry-associated fibrosis risk.