In Vitro Models for Studying Respiratory Host-Pathogen Interactions.

Respiratory diseases and lower respiratory tract infections are among the leading cause of death worldwide and, especially given the recent severe acute respiratory syndrome coronavirus-2 pandemic, are of high and prevalent socio-economic importance. In vitro models, which accurately represent the lung microenvironment, are of increasing significance given the ethical concerns around animal work and the lack of translation to human disease, as well as the lengthy time to market and the attrition rates associated with clinical trials. This review gives an overview of the biological and immunological components involved in regulating the respiratory epithelium system in health, disease, and infection. The evolution from 2D to 3D cell biology and to more advanced technological integrated models for studying respiratory host-pathogen interactions are reviewed and provide a reference point for understanding the in vitro modeling requirements. Finally, the current limitations and future perspectives for advancing this field are presented

An electroactive and thermo-responsive material for the capture and release of cells

Non-invasive collection of target cells is crucial for research in biology and medicine. In this work, we combine a thermo-responsive material, poly(N-isopropylacrylamide), with an electroactive material, poly(3,4-ethylene-dioxythiopene):poly(styrene sulfonate), to generate a smart and conductive copolymer for the label-free and non-invasive detection of the capture and release of cells on gold electrodes by electrochemical impedance spectroscopy. The copolymer is functionalized with fibronectin to capture tumor cells, and undergoes a conformational change in response to temperature, causing the release of cells. Simultaneously, the copolymer acts as a sensor, monitoring the capture and release of cancer cells by electrochemical impedance spectroscopy. It is expected that this platform has the potential to play a role in top-notch label-free electrical monitoring of human cells obtaining in clinic.This project has received funding from University of the Basque Country (PIF16/204 and MOV19/41), the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 842356, Gobierno de España, Ministerio de Economía y Competitividad, with Grant No. BIO2016-80417-P (AEI/FEDER, UE) and Gobierno Vasco Dpto. Educación for the consolidation of the research groups (IT1271-19)

Thermo-responsive poly(ionic liquid) valves for microfluidic devices

Poly(ionic liquid)s (PIL) are a class of ionic liquids that feature polymerizable groups in the cation, the anion or both. They retain most of the properties present in ionic liquids, including ionic conductivity, low vapour pressure and tunable physico-chemical properties. Several phosphonium ionic liquids have been shown to possess a lower critical solution temperature, making them suitable materials for the synthesis of temperature-responsive smart materials.1,2 Herein, we present the synthesis of a thermo-responsive tributylhexyl phosphonium 3-sulfopropyl acrylate (PSPA) crosslinked PIL, followed by its inclusion in a microfluidic device to be used as a temperature controlled valve. After polymerization, the hydrogels were swollen in deionized water and had their temperature-induced shrinking measured with a digital microscope from 20 °C to 70 °C, in 10 °C intervals. Measurements indicate a relative surface contraction of the hydrogels, in deionized water, of 34.04% ± 4.62% (n = 3) at a temperature of 50 °C, and 53.37% ± 12.55% (n = 3) at a temperature of 70 °C. Following this, microfluidic devices were constructed using poly(methyl methacrylate) and pressure sensitive adhesive. After assembly, the chips were fitted on a heating element and connected to a syringe pump with a flow rate of 500 nL·min-1. A flow microsensor was used to analyze the shrinking-swelling efficiency of the PILc hydrogel valves. A temperature of 50 °C was applied to shrink the hydrogels, followed by a temperature of 25 °C to re-swell the hydrogels. The time required for the PILc valve to open was ~6s, allowing water flow (~140 nL·min-1), while the time required for it to close was ~10s. This process was repeated for six times indicating the possibility of using these valves for multiple times. In conclusion, the results confirm the applicability of PSPA hydrogels as thermally controlled valves in microfluidic devices. Furthermore, the next steps of this study will focus on the optimization of the microfluidic device to ensure maximum efficiency in closing and opening the channel, while also increasing the repeatability of the operation

Proneuropeptide Y processing in large dense-core vesicles: manipulation of prohormone convertase expression in sympathetic neurons using adenoviruses

NRC publication: Ye

Red-Handed: Collaborative Gesture Interaction with a Projection Table

Collaboration is an essential mechanism for productivity. Projection tables such as the SociaDesk enable collaboration through the sharing of audio, video and data. To enhance this form of interaction, it is beneficial to enable local, multi-user interaction with this media. This paper introduces a computer vision-based gesture recognition system that detects and stores the gestures of multiple users at the SociaDesk. This system was designed to be a submodule of high-level applications that implement multi-user interaction. With such a system, users can collaboratively interact with software-based tools at a projection table.La collaboration est un m\ue9canisme essentiel \ue0 la productivit\ue9. Les tables de projection, comme SociaDesk, permettent la collaboration gr\ue2ce au partage de l'audio, de la vid\ue9o et des donn\ue9es. Pour am\ue9liorer cette forme d'interaction, il est avantageux de permettre \ue0 de multiples utilisateurs d'interagir localement avec ce m\ue9dia. Cet article pr\ue9sente un syst\ue8me de reconnaissance gestuelle bas\ue9e sur la vision qui d\ue9tecte et enregistre les gestes de multiples utilisateurs \ue0 la table SociaDesk. Ce syst\ue8me a \ue9t\ue9 con\ue7u comme un sous-module d'applications de haut niveau qui permettent les interactions entre de multiples utilisateurs. Gr\ue2ce \ue0 ce syst\ue8me, les utilisateurs peuvent interagir de fa\ue7on collaborative avec des outils logiciels \ue0 une table de projection.NRC publication: Ye

Conducting polymer-ECM scaffolds for human neuronal cell differentiation

Three-dimensional (3D) cell culture formats more closely resemble tissue architecture complexity than two-dimensional (2D) systems, which are lacking most of the cell-cell and cell-microenvironment interactions of the in vivo milieu. Scaffold-based systems integrating natural biomaterials are extensively employed in tissue engineering to improve cell survival and outgrowth, by providing the chemical and physical cues of the natural extracellular matrix (ECM). Using the freeze-drying technique, porous 3D composite scaffolds consisting of poly (3,4-ethylene-dioxythiophene) doped with polystyrene sulfonate (PEDOT:PSS), containing ECM components (i.e., collagen, hyaluronic acid and laminin) were engineered for hosting neuronal cells. The resulting scaffolds exhibit a highly porous microstructure and good conductivity, determined by scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS), respectively. These supports boast excellent mechanical stability and water uptake capacity, making them ideal candidates for cell infiltration. SH-SY5Y human neuroblastoma cells showed enhanced cell survival and proliferation in the presence of ECM compared to PEDOT:PSS alone. Whole-cell patch-clamp recordings acquired from differentiated SHSY5Y cells in the scaffolds demonstrated that ECM constituents promote neuronal differentiation in situ. These findings reinforce the usability of 3D conducting supports as engineered highly biomimetic and functional in vitro tissue-like platforms for drug or disease modelling

Capture and Release of Cancer Cells Through Smart Bioelectronics.

Noninvasive collection of target cells such as circulating tumor cells (CTCs) is crucial for biology and medicine research. Conventional methods of cell collection are often complex, requiring either size-dependent sorting or invasive enzymatic reactions. Here, we show the development of a functional polymer film, which combines the thermoresponsive poly(N-isopropylacrylamide) and the conducting poly(3,4-ethylenedioxythiopene)/poly(styrene sulfonate), and its use for the capture and release of CTCs. When coated onto microfabricated gold electrodes, the proposed polymer films are capable of noninvasively capturing and controllably releasing cells while, at the same time, monitoring these processes with conventional electrical measurements

A Conformable Organic Electronic Device for Monitoring Epithelial Integrity at the Air Liquid Interface.

Publication status: PublishedFunder: Ikerbasque, Basque Foundation for Science; doi: http://dx.doi.org/10.13039/501100003989Funder: Departamento de Salud del Gobierno VascoFunder: FUNDACION Vital FundazioaFunder: Gobierno de EspañaAir liquid interfaced (ALI) epithelial barriers are essential for homeostatic functions such as nutrient transport and immunological protection. Dysfunction of such barriers are implicated in a variety of autoimmune and inflammatory disorders and, as such, sensors capable of monitoring barrier health are integral for disease modelling, diagnostics and drug screening applications. To date, gold-standard electrical methods for detecting barrier resistance require rigid electrodes bathed in an electrolyte, which limits compatibility with biological architectures and is non-physiological for ALI. This work presents a flexible all-planar electronic device capable of monitoring barrier formation and perturbations in human respiratory and intestinal cells at ALI. By interrogating patient samples with electrochemical impedance spectroscopy and simple equivalent circuit models, disease-specific and patient-specific signatures are uncovered. Device readouts are validated against commercially available chopstick electrodes and show greater conformability, sensitivity and biocompatibility. The effect of electrode size on sensing efficiency is investigated and a cut-off sensing area is established, which is one order of magnitude smaller than previously reported. This work provides the first steps in creating a physiologically relevant sensor capable of mapping local and real-time changes of epithelial barrier function at ALI, which will have broad applications in toxicology and drug screening applications

Development and application of laser induced incandescence (LII) as a diagnostic for soot particulate measurements

In this paper we describe our development of the LII technique for point measurement in flames and the calibration of the technique using a simple laminar diffusion flame. Since LII provides only relative soot volume fraction measurements, an absolute calibration is necessary. The radial soot volume fraction profiles in the laminar diffusion flame were measured by Abel inversion of line-of-sight attenuation measurements at 532 and 1064 nm. We have implemented a numerical model of the LII processes to aid in the interpretation of experimental results. A description of the LII technique and its calibration are discussed. The application of LII to a confined C3H8/air diffusion flame and some results of the model predictions and their comparison to experiment will be included in the presentation.NRC publication: Ye