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Carugo, D.

Publications and source records attributed to Carugo, D..

4 recordsLinked to original sources

The material properties of the cell determine microbubble-induced cell deformation and permeabilisation

Mechanical properties influence how cells withstand and transmit force, but their role in clinically relevant, high-frequency therapeutic perturbations remains poorly understood. Ultrasound-stimulated microbubbles can locally deform cells and tissues to enhance drug delivery, yet therapeutic responses vary markedly across mechanical microenvironments. How cellular material properties govern microbubble-cell interactions at megahertz loading rates - well beyond the range accessible to conventional mechanobiology - remains unresolved. Here we combine ultra-high-speed imaging with digital image correlation to map microbubble-induced deformation in living cells at ultrasound frequencies. We show that oscillating microbubbles generate harmonic deformation waves whose spatial decay defines a micrometre-scale attenuation length governed by cytoskeletal organisation and intracellular viscoelastic dissipation. Pharmacological softening or stiffening alters both deformation propagation and wave speed, and these mechanical changes predict permeabilisation efficiency in tumour-derived and primary human bone-marrow stromal cells. These findings establish cellular viscoelasticity as a determinant of microbubble bioeffects and suggest that tissue mechanical state can be used as a design parameter for ultrasound-mediated therapeutic delivery.

bioengineering↗

Effect of human urinary microenvironment and fluid flow on antibiotic and phage therapy efficacy against uropathogenic Escherichia coli

Urinary tract infections (UTI) remain a major global health burden, with high recurrence despite antibiotic treatment. The escalating prevalence of antimicrobial resistance further compromises therapeutic efficacy, contributing to an estimated 260,000 deaths annually. Conventional in vitro susceptibility assays often fail to predict clinical outcomes, underscoring the urgent need for physiologically relevant infection models. Here, we examined how microenvironmental complexity shapes uropathogenic Escherichia coli (UPEC) responses to antibiotics and bacteriophages using: human urine, a three-dimensional urothelial microtissue model (3D-UHU), and a novel mesofluidic system (P-FLO) that introduces physiologically relevant flow dynamics to the 3D-UHU. P-FLO was engineered from cost-effective 3D-printed components compatible with standard Transwell systems. Among the antibiotics tested, nitrofurantoin exhibited the greatest potency in minimum inhibitory concentration assays, but it failed to fully eradicate infection within the more physiological 3D-UHU model. A bacteriophage cocktail (LCPR1) showed markedly reduced activity in urine compared with nutrient-rich media, highlighting the influence of infection-site conditions. In contrast, in 3D-UHU, LCRP1 modulated host responses without reducing bacterial burden. Combination therapy (nitrofurantoin + LCPR1) eliminated planktonic bacteria under static conditions but offered no added benefit against adherent or intracellular populations relative to antibiotic monotherapy. Incorporating flow revealed additional layers of complexity, where shear stress induced bacterial elongation and attachment and altered drug performance, diminishing the efficacy of nitrofurantoin and combination therapy against planktonic populations despite increased drug exposure. Together, these findings demonstrate that the bladder microenvironment and its mechanical forces modulate host-pathogen interactions and profoundly influence UPEC infection dynamics and therapeutic outcomes, emphasizing the need for advanced, physiologically informed models to guide treatment strategies in the post-antibiotic era.

microbiology↗

3D bone printing via primed differentiation of stem cells with ultrasound (3DBonUS)

Bone disorders and skeletal defects represent a significant clinical challenge. Tissue engineering and regenerative medicine (TERM) strategies using 3D bioprinting have emerged as promising alternatives, but still limited by the inability of directing stem cell differentiation in a controlled and reproducible manner. Advancing beyond this, we are proposing 3D bone printing via primed differentiation of stem cells with ultrasound (referred to here as 3DBonUS). This approach synergistically integrates low-intensity pulsed ultrasound (LIPUS) with a microfluidic-assisted 3D bioprinting platform enabling the biophysical stimulation of human bone marrow stromal cells (HBMSCs) during extrusion, promoting osteogenic differentiation without the need for post-fabrication treatments. Moreover, the incorporation of microbubbles enhanced the effects of LIPUS by amplifying mechanical signals at the cellular level. 3DBonUS was found to significantly upregulate key osteogenic markers (RUNX-2, ALP, COL1A1, BMP-2, OCN, OPN) as confirmed by immunofluorescence and RT-qPCR analysis. Furthermore, the LIPUS-treated constructs showed a significant increase in alkaline phosphatase activity and calcium deposition, indicating enhanced mineralisation. The 3DBonUS strategy represents a new modality in skeletal biofabrication, harnessing targeted minimally-invasive mechanical stimulation, with potential for manufacturing scalability and clinical application. Future studies will aim to validate 3DBonUS in vivo to assess the ultimate regenerative potential with enhanced osteogenic properties.

bioengineering↗

Creating supported plasma membrane bilayers using acoustic pressure

Model membrane systems are essential tools for biology, enabling study of biological processes in a simplified setting to reveal the underlying physicochemical principles. As cell-derived membrane systems, giant plasma membrane vesicles (GPMVs) constitute an intermediate model between native cellular plasma and artificial membranes. Certain applications, however, require planar membrane surfaces. Here, we report a novel approach for creating supported plasma membrane bilayers (SPMBs) by bursting cell-derived GPMVs using an ultrasonic pressure field generated within an acoustofluidic device. We show that the mobility of outer leaflet molecules is preserved in SPMBs, suggesting that they are accessible on the surface of the bilayers. Such model membrane systems will be useful for many applications requiring detailed characterization of plasma membrane dynamics.

biophysics↗