Biology subjects

Rauti, R.

Publications and source records attributed to Rauti, R..

5 recordsLinked to original sources

bioRxiv2025

Shear Stress Modulates Endothelial Ca2+ Signaling and Barrier Integrity in a Microfluidic Organ-on-a-Chip Platform

Endothelial cells (ECs) line the blood vessels and form the primary barrier between the bloodstream and the brain. Blood flow exerts a modulatory effect on the endothelial phenotype, and evidence indicates that capillary-like fluid shear stress enhances endothelial tight junctions and transporters. ECs possess mechanosensitive channels that activate endothelial responses and modulate their functions. Among the various responses to shear stress, morphological adaptations have been the most extensively studied, while functional live responses remain mostly unexplored. Calcium has been identified as key modulators that translates mechanical stimuli into biological processes, regulating endothelial activity. In this study we investigate the effect of acute and long-term shear stress on endothelial cells through live calcium imaging and immunocytochemistry, by using a modular 3D printed organ-on-a-chip, capable of simulating in-vivo capillary and enabling the possibility to study cellular crosstalk.

physiology↗

bioRxiv2025

Engeneering the neurovascular unit: a novel sensorized microfluidic platform to study barrier function and maturation

Central nervous system diseases pose a significant challenge for the development of effective drugs and therapies. A major limiting factor is the neurovascular unit (NVU), which is both anatomically complex and characterized by a highly selective barrier. Conventional 2D in-vitro models and in-vivo animal models do not adequately replicate its pathophysiology. Organ-on-a-Chip technology provides a powerful platform to model the NVU, enabling replication of its anatomical and functional features within a dynamic microenvironment that closely mimics the human brain. However, the requirement for specialized facilities and technical expertise limits accessibility, reducing broader translational applications. Additionally, conventional endpoint analyses constrain real-time monitoring of cellular behavior. Here, we present and validate a novel bi-modular microfluidic chip that offers an easy-to-use and scalable solution for studying cellular cross-talk, while enabling live imaging and real-time measurements. The model incorporates human endothelial cells and primary neurons that were investigated through immunofluorescence and live imaging. The design overcomes key fabrication challenges and integrates a simplified method for Trans-Epithelial/Endothelial Electrical Resistance (TEER) monitoring, allowing in situ real-time assessment of barrier integrity. Overall, this platform represents a robust and versatile tool for in-vitro studies of the NVU, facilitating comprehensive evaluation of its structural and functional dynamics. Our microfluidic NVU-on-chip represents a significant advancement in NVU modelling, providing a versatile platform for CNS drug screening, disease modelling, and personalized medicine applications.

bioengineering↗

bioRxiv2025

Transepithelial/endothelial electrical measurement using a low-cost and customizable Arduino-based sensor

Transepithelial/transendothelial electrical resistance (TEER) is a label-free assay that is commonly used to assess tissue barrier integrity. Although commercial TEER meters are available, they are expensive and difficult to customize, which hinders researchers hoping to incorporate them in other research platforms. In the past few years, microcontrollers have risen in popularity for electrical signaling and general programming, of which Arduino is the most popular platform due to its scalability, simplicity and low price. This work presents the development of a completely customized, user-friendly and low-cost TEER meter that is Arduino-based and capable of continuous measurements and automated data collection. We demonstrate the stability of the instrument to measure long-term real-time barrier formation and disruption of an epithelial and endothelial cell line. The design simplicity and low-cost of the components make this technology transferrable to other laboratories for TEER and biological barriers research.

bioengineering↗

bioRxiv2023

Impact of magnetite nanowires orientation on morphology and activity of in vitro hippocampal neural networks

Nanomaterials design, synthesis and characterization are ever-expanding approaches towards developing biodevices or neural interfaces to treat neurological diseases. The ability of nanomaterials features, to tune neuronal networks morphology or functionality is still under study. In this work, we unveil how, when interfacing mammalian brain cultured neurons, iron oxide nanowires (NWs) orientation affects neuronal and glial densities, and network activity. Iron oxide NWs were synthesized by electrodeposition, fixing the diameter to 100 nm and the length to 1 m. Scanning electron microscopy, Raman and contact angle measurements were performed to characterize the NWs morphology, chemical composition and hydrophilicity. Hippocampal cultures were seeded on NWs devices and after 14 days the cell morphology was studied by immunocytochemistry and confocal microscopy. Live calcium imaging was performed to study neuronal activity. Using random (R-NWs) a higher neuronal and glial cell densities were obtained compared with the control and vertical (V-NWs), while using V-NWs more stellate glial cells were found. R-NWs produced a reduction in neuronal activity while V-NWs increased the neuronal network activity, possibly due to higher neuronal maturity and a lower number of GABAergic neurons, respectively. These results highlight the potential of NWs manipulations to design ad hoc regenerative interfaces.

bioengineering↗

bioRxiv2021

Effect of SARS-CoV-2 proteins on vascular permeability

SARS-CoV-2 infection leads to severe disease associated with cytokine storm, vascular dysfunction, coagulation, and progressive lung damage. It affects several vital organs, seemingly through a pathological effect on endothelial cells. The SARS-CoV-2 genome encodes 29 proteins, whose contribution to the disease manifestations, and especially endothelial complications, is unknown. We cloned and expressed 26 of these proteins in human cells and characterized the endothelial response to overexpression of each, individually. Whereas most proteins induced significant changes in endothelial permeability, nsp2, nsp5_c145a (catalytic dead mutant of nsp5) and nsp7 also reduced CD31, and increased von Willebrand factor expression and IL-6, suggesting endothelial dysfunction. Using propagation-based analysis of a protein-protein interaction (PPI) network, we predicted the endothelial proteins affected by the viral proteins that potentially mediate these effects. We further applied our PPI model to identify the role of each SARS-CoV-2 protein in other tissues affected by COVID-19. Overall, this work identifies the SARS-CoV-2 proteins that might be most detrimental in terms of endothelial dysfunction, thereby shedding light on vascular aspects of COVID-19.

cell biology↗