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Rasponi, M.

Publications and source records attributed to Rasponi, M..

8 recordsLinked to original sources

An Innervated and Vascularized HNSCC-on-a-Chip Model Built on Defined and Tunable Engineered Extracellular Matrices

Understanding the tumor microenvironment (TME) requires experimental platforms that faithfully recapitulate its key components. Here, we present an innervated and vascularized head and neck squamous cell carcinoma (HNSCC)-on-a-chip platform built with fully defined and tunable engineered extracellular matrices (eECMs). In a stepwise increase of complexity, we first co-cultured patient-derived HNSCC cells, cancer-associated fibroblasts, and endothelial cells within tailored eECMs, revealing matrix-dependent differences in self-organization and chemotherapeutic sensitivity. We then integrated these 3D constructs into a cancer-vasculature-interface, which enabled analysis of eECM-dependent directional collective migration and metastatization. Finally, we incorporated HNSCC-specific innervation through injectable 3D human bioengineered trigeminal ganglia, establishing a chip-based innervation-tumor-vasculature tri-interface. Together, this all-human platform captures fundamental determinants of HNSCC progression, including a fully defined ECM, vasculature, and innervation, within a single modular system that is broadly adaptable for interrogating how the tumor microenvironment shapes solid tumor behavior and therapeutic responses. TeaserHNSCC-on-a-chip integrates defined ECM, vasculature, and innervation to investigate tumor behavior and therapeutic responses.

bioengineering↗

Von Willebrand Factor Deficiency Impairs Vascular Morphogenesis via Angiopoietin-2: Relevance for Gut Angiodysplasia

Management of recurrent gastrointestinal (GI) bleeding is a clinical unmet need for patients with Von Willebrand disease (VWD) and is linked to the presence of gut vascular malformations (angiodysplasia). We previously demonstrated that von Willebrand factor (VWF) regulates angiogenesis and vascular integrity, the likely mechanism underlying angiodysplasia. VWF controls the storage of the angiogenesis regulator Angiopoietin-2 (Angpt-2) in endothelial cells (EC), suggesting a candidate for the genesis of angiodysplasia; however, no direct evidence of the role of Angpt-2 in VWF-dependent angiogenesis is available. Here we use VWF-deficient HUVEC, and endothelial colony forming cells (ECFCs) from severe VWD patients and find that loss of VWF in EC results in increased Angpt-2 expression through a positive feedback loop via the Angpt-2-TIE2-AKT-FOXO1 pathway. We also show an imbalance of the Angpt/Tie2 pathway in vivo. In the gut of VWF-deficient mice, Angpt-2 expression is increased whilst Angpt-1 expression is decreased; this correlates with reduced expression of the pericyte marker NG2. These data suggest that VWF regulates the Angpt/Tie2 balance in the gut. To investigate the functional defects caused by loss of VWF, we use a fibrin bead assay and show that VWF-deficient HUVEC present increased sprouting. We develop a microfluidic model of 3D vasculogenesis/angiogenesis and find that ECFCs from VWD patients exhibit defective remodeling and abnormal lumen formation compared to healthy controls. Importantly, inhibition of Angpt-2 reduces sprouting in VWF-deficient HUVEC and normalises vascular networks in ECFCs from severe VWD, suggesting Angpt-2 inhibitors may be effective in VWD patients with GI bleeding and angiodysplasia. Key pointsO_LIEndothelial VWF regulates multiple steps of angiogenesis, including sprouting and lumen formation. C_LIO_LIVWF regulates Angpt-2 storage and expression, and Angpt-2 blockade normalises defective angiogenesis in VWD ECFCs. C_LI Visual Abstract O_FIG O_LINKSMALLFIG WIDTH=170 HEIGHT=200 SRC="FIGDIR/small/675051v1_ufig1.gif" ALT="Figure 1"> View larger version (19K): org.highwire.dtl.DTLVardef@150eb15org.highwire.dtl.DTLVardef@179e6beorg.highwire.dtl.DTLVardef@1bcadborg.highwire.dtl.DTLVardef@a30fb8_HPS_FORMAT_FIGEXP M_FIG VWF deficiency in HUVECs results in increased Angpt-2 release and expression via the Tie2-Akt-FOXO1 pathway. A. Model pathway for the regulation of Angpt-2 levels by VWF. Loss of VWF results in increased Angpt-2 release from endothelial cells; Angpt-2 binds to and inhibits the Tie2 receptor, decreasing its phosphorylation as well as the downstream phosphorylation of Akt and FOXO1; this leads to FOXO1 activation and an increase expression of Angpt-2, generating a feedback loop. B. Model for the pathogenesis of angiodysplasia in VWD. In the absence of VWF, the increase in Angpt-2 disrupts vascular morphogenesis through multiple mechanisms: increased sprouting, impaired vascular remodelling and an imbalance between Angpt-1 and Angpt-2 in the gut. Figure generated with Biorender. C_FIG

cell biology↗

Cardiac fibroblasts cellular anisotropy is determined by YAP-dependent cellular contractility and ECM production

Cardiac fibroblasts (CFbs) determine the topological arrangement and the anisotropy of the heart tissue - essential features for maintaining tissue integrity and function - through the production and remodeling of the extracellular matrix (ECM). Under pathological conditions, CFbs can activate into myofibroblasts and promote maladaptive ECM remodeling that may lead to heart failure. Yes-Associated Protein (YAP) - a key player in cardiac fibrosis onset - has been implicated in CFb activation but its role in coordinating the supracellular organization of CFbs and in shaping the instructive properties of the ECM remains poorly understood. We addressed these questions by generating CFbs from wild-type (WT) and YAP knockout (KO) human embryonic stem cells. YAP depletion reduced the expression of cardiogenic markers and altered the transcriptomic profile of ECM- and contractility-related genes. We further demonstrated that YAP expression is required for CFbs monolayer alignment, and its absence resulted in reduced ECM deposition, decreased anisotropy, and diminished force generation. Pharmacological inhibition of cell contractility closely mirrored YAP KO phenotype, suggesting that YAP regulates both monolayer organization and ECM structure through its control over contractility. ECM cross-seeding experiments confirmed the role of ECM as a structural guide for cellular alignment. Moreover, cardiomyocytes cultured on KO CFb-derived ECM exhibited impaired sarcomere organization and altered calcium dynamics. Together, these findings demonstrate that YAP activity in CFbs governs the structural and functional properties of the ECM, influencing both fibroblast alignment and cardiomyocyte activity. Moreover, they underscore the critical role of YAP in maintaining the supracellular organization and mechanical integrity of cardiac tissue.

cell biology↗

An iPSC-derived bio-inspired scaffold modelling the structure and the effects of extracellular matrix in cardiac fibrosis

Cardiac fibrosis occurs following insults to the myocardium and is characterized by the abnormal accumulation of non-compliant extracellular matrix (ECM), which compromises cardiomyocyte contractile activity and eventually leads to heart failure. This phenomenon is driven by the differentiation of cardiac fibroblasts (cFbs) into myofibroblasts and results in changes in ECM biochemical, structural and mechanical properties. The lack of predictive in vitro models of heart fibrosis has so far hampered the search for innovative treatments. Here, we devised a single-step decellularization protocol to obtain and thoroughly characterize the biochemical and micro-mechanical properties of the ECM secreted by activated cFbs differentiated from human induced pluripotent stem cells (iPSCs). We activated iPSC-derived cFbs to the myofibroblast phenotype by tuning basic fibroblast growth factor (bFGF) and transforming growth factor beta 1 (TGF-{beta}1) signalling and confirmed that activated cells acquired key features of myofibroblast phenotype, like SMAD2/3 nuclear shuttling, the formation of aligned alpha-smooth muscle actin (-SMA)-rich stress fibres and increased focal adhesions (FAs) assembly. Next, we used Mass Spectrometry, nanoindentation, scanning electron and confocal microscopy to unveil the characteristic composition and the visco-elastic properties of the abundant, collagen-rich ECM deposited by cardiac myofibroblasts in vitro. Finally, we demonstrated that the fibrotic ECM activates mechanosensitive pathways in iPSC-derived cardiomyocytes, impacting on their shape, sarcomere alignment, phenotype, and calcium handling properties. We thus propose human bio-inspired decellularized matrices as animal-free, isogenic cardiomyocyte culture substrates recapitulating key pathophysiological changes occurring at the cellular level during cardiac fibrosis.

cell biology↗

Modelling Osteoarthritis pathogenesis through Mechanical Loading in an Osteochondral Unit-on-Chip

A cure for osteoarthritis (OA), the most prevalent musculoskeletal disease, remains an unmet need. Investigating the molecular and cellular processes leading to OA is challenged by the absence of human models that capture the complex interplay among different tissues in the joint under pathophysiological mechanical loading. In this study, we have engineered an OsteoChondral Unit (OCU)-on-chip system where composite hyaline cartilage - mineralized osseous microtissue analogues are exposed to controlled, tissue-specific compression regimes akin to those of the OCU in vivo. Through single-cell transcriptomic analysis, we demonstrate the critical relevance of the mineralized layer in inducing chondrocyte subpopulations implicated in the progression of OA. Upon exposure to hyperphysiological loading, the OCU-on-chip captures early phenotypic traits of OA pathogenesis, comprising alterations of subchondral mineral content and acquisition of previously described OA genetic signatures. This system enabled to identify novel upstream drivers of OA metabolic changes, including mechanically induced ribosomal alterations, as well as associated molecular targets towards the development of disease-modifying OA therapies.

bioengineering↗

GZMKhigh CD8+ T effector memory cells are associated with CD15high neutrophil abundance in early-stage colorectal tumors and predict poor clinical outcome.

Tumor contexture has emerged as a major prognostic determinant and tumor infiltrating CD8+ T cells have been associated with a better prognosis in several solid tumors, including early-stage colorectal cancer (CRC). However, the tumor immune infiltrate is highly heterogeneous and understanding how the interplay between different immune cell compartments impacts on the clinical outcome is still in its infancy. Here, we describe in a prospective cohort a novel CD8+ T effector memory population, which is characterized by high levels of Granzyme K (GZMKhigh CD8+ TEM) and is correlated with CD15high tumor infiltrating neutrophils. We provide both in vitro and in vivo evidence of the role of stromal cell-derived factor 1 (CXCL12/SDF-1) in driving functional changes on neutrophils at the tumor site, promoting their retention and increasing the crosstalk with CD8+ T cells. Mechanistically, as a consequence of the interaction with neutrophils, CD8+ T cells are skewed towards a CD8+ TEM phenotype and produce high levels of GZMK, which in turn decreases E-cadherin pathway. The correlations of GZMKhigh CD8+ TEM and neutrophils with both tumor progression in mice and early relapse in CRC patients demonstrate the role of GZMKhigh CD8+ TEM in promoting malignancy. Indeed, a gene signature defining GZMKhigh CD8+ TEM was associated with worse prognosis on a larger independent cohort of CRC patients and a similar analysis was extended to lung cancer (TCGA). Overall, our results highlight the emergence of GZMKhigh CD8+ TEM in early-stage CRC tumors as a hallmark driven by the interaction with neutrophils, which could implement current patient stratification and be targeted by novel therapeutics.

immunology↗

Physiologic flow-conditioning limits vascular dysfunction in engineered human capillaries

Hemodynamics play a central role in the health and disease of the coronary and peripheral vascular systems. Vessel-lining endothelial cells are known mechanosensors, responding to disturbances in flow - with mechanosensitivity hypothesized to change in response to metabolic demands. The health of our smallest microvessels have been lauded as a prognostic marker for cardiovascular health. Yet, despite numerous animal models, studying these small vessels has proved difficult. Microfluidic technologies have allowed a number of 3D vascular models to be developed and used to investigate human vessels. Here, two such systems are employed for examining 1) interstitial flow effects on neo-vessel formation, and 2) the effects of flow-conditioning on vascular remodelling following sustained static culture. Interstitial flow is shown to enhance early vessel formation via significant remodeling of vessels and interconnected tight junctions of the endothelium. In formed vessels, continuous flow maintains a stable vascular diameter and causes significant remodeling, contrasting the continued anti-angiogenic decline of statically cultured vessels. This study is the first to couple complex 3D computational flow distributions and microvessel remodeling from microvessels grown on-chip (exposed to flow or no-flow conditions). Flow-conditioned vessels (WSS < 1Pa for 30 micron vessels) increase endothelial barrier function, result in significant changes in gene expression and reduce reactive oxygen species and anti-angiogenic cytokines. Taken together, these results demonstrate microvessel mechanosensitivity to flow-conditioning, which limits deleterious vessel regression in vitro, and could have implications for future modeling of reperfusion/no-flow conditions.

bioengineering↗

A human stem cell-derived neurosensory-epithelial circuitry on-a-chip to model herpes simplex virus reactivation

Both emerging viruses and well-known viral pathogens endowed with neurotropism can either impair directly the neuronal functions or induce physio-pathological changes by diffusing from the periphery through neurosensory-epithelial connections. However, the current lack of an in vitro system modeling the connectivity between human neurons and peripheral tissues excludes the analysis of viral latency and reactivation and the assessment of natural/artificial induced anti-viral immunity. In this study, we developed the first stable topographic neurosensory-epithelial connection on-a-chip using human stem cell derived dorsal root ganglia (DRG) sensory neurons. Bulk and single cell transcriptomics showed that different combinations of key receptors for Herpes Simplex Virus 1 (HSV-1) are expressed by each sensory neuronal cell type. This neuronal-epithelial circuitry enabled a detailed analysis of the HSV infectivity faithfully modeling its dynamics and cell type specificity. The reconstitution of an organized connectivity between human sensory neurons and keratinocytes into microfluidic chips provides for the first time a powerful in vitro platform to model viral latency and reactivation of human viral pathogens.

microbiology↗