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Biology subjects

Fava, E.

Publications and source records attributed to Fava, E..

4 recordsLinked to original sources

MRI-Compatible Rigid Head Holders for Artifact-Free Multimodal Imaging in Mice

PurposeHigh-resolution intravital microscopy allows cellular-scale analysis of the brain in vivo but is greatly sensitive to physiological motion. Combining optical microscopy with magnetic resonance imaging (MRI) in the same animal could relate cellular and mesoscale functional readout to whole-brain structural information, but this requires head holders that are both mechanically rigid and MRI compatible. Conventional metallic head holders introduce MRI artifacts, whereas many nonmetallic alternatives lack sufficient stability for chronic microscopy. Thus, we developed rigid, MRI-compatible head holders engineered from 3D-printed zirconia ceramics to reduce motion during microscopy while preserving MRI image quality. MethodsHead holders were designed for mouse cranial fixation and fabricated from zirconia ceramics using additive manufacturing. We quantified motion artifacts during two-photon and multimodal widefield imaging of the mouse cortex and assessed their impact on neuronal calcium activity, functional connectivity, and hemodynamic readouts. MRI compatibility was evaluated by measuring image quality in the presence of the head holder. ResultsThe ceramic head holders provided mechanical stability to reduce motion artifacts to micrometer levels during intravital imaging. The head holders produced no detectable susceptibility artifacts in MRI, and image contrast was comparable to control acquisitions performed without head holder. Sequential optical and MRI imaging of the same brain regions established artifact-minimized multimodal data acquisition within the same animal. ConclusionsNon-metallic ceramic head holders support longitudinal multimodal studies that combine high-resolution optical microscopy with whole-brain MRI measurements in the same animal.

neuroscience↗

Gain efficiency with streamlined and automated data processing: Examples from high-throughput monoclonal antibody production

Data management and sample tracking in complex biological workflows are essential steps to ensure necessary documentation and guarantee the reusability of data and metadata. Currently, these steps pose challenges related to correct annotation and labeling, error detection, and safeguarding the quality of documentation. With growing acquisition of biological data and the expanding automatization of laboratory workflows, manual processing of samples is no longer favorable, as it is time- and resource-consuming, is prone to biases and errors, and lacks scalability and standardization. Thus, managing heterogeneous biological data calls for efficient and tailored systems, especially in laboratories run by biologists with limited computational expertise. Here, we showcase how to meet these challenges with a modular pipeline for data processing, facilitating the complex production of monoclonal antibodies from single B-cells. We present best practices for development of data processing pipelines concerned with extensive acquisition of biological data that undergoes continuous manipulation and analysis. Moreover, we assess the versatility of proposed design principles through a proof-of-concept data processing pipeline for automated induced pluripotent stem cell culture and differentiation. We show that our approach streamlines data management operations, speeds up experimental cycles and leads to enhanced reproducibility. Finally, adhering to the presented guidelines will promote compliance with FAIR principles upon publishing.

cell biology↗

An ex vivo human model for safety assessment of immunotoxicity of engineered nanomaterials

The unique physicochemical properties of nanomaterials (NM) and engineered nanomaterials (ENM) have pushed their use in many applications ranging from medicine to the food industry, textiles, and many more fields. Thus, human exposure to NM and ENM is growing by the day. However, the current toxicity tests do not reflect the special characteristics of ENM and are not developed for ENM risk assessment. Here we propose a high-throughput cell-based assay using human peripheral blood mononuclear cells (PBMCs) that can monitor the effects of NM and ENM on cytotoxicity and innate immunity. The proposed assay is fully automated and miniaturized, with excellent assay performance parameters (Z-score >0.5), amenable for large screening campaigns in industrial setting. Immunotoxicity data for ENM safety assessment are collected in dose-response format. At different states, multiparametric readouts for cytotoxicity, and innate immunity are conducted in a combinatorial method, avoiding ENM-induced bias by endotoxin contamination. Integrating this high-dimensional data, allows (i) holistic safety assessment of immunotoxicity effects caused by ENM, classifying safe and toxic ENM phenotypes, and (ii) to deconvolve mode of action of the ENM effect on the PBMCs. As added value the data obtained can be used to troubleshoot ENM or for a safe-by-design approach in product development.

immunology↗

Human iPSC-derived brain endothelial microvessels in a multi-well format enable permeability screens of anti-inflammatory drugs

Optimizing drug candidates for blood-brain barrier (BBB) penetration in humans remains one of the key challenges and many devastating brain diseases including neurodegenerative diseases still do not have adequate treatments. So far, it has been difficult to establish state-of-the-art human stem cell derived in vitro models that mimic physiological barrier properties including a 3D microvasculature in a format that is scalable enough to screen drugs for BBB penetration in early drug development phases. To address this challenge, we established human induced pluripotent stem cell (iPSC)-derived brain endothelial microvessels in a standardized and scalable multi-well plate format. iPSC-derived brain microvascular endothelial cells (BMECs) were supplemented with primary cell conditioned media and grew to intact microvessels in 10 days of culturing. Produced microvessels show a typical BBB phenotype including endothelial protein expression, tight-junctions and polarized localization of efflux transporter. Microvessels exhibited physiological relevant trans-endothelial electrical resistance (TEER), were leak-tight for 10 kDa dextran-Alexa 647 and strongly limited the permeability of sodium fluorescein (NaF). Permeability tests with reference compounds confirmed the suitability of our model as platform to identify potential BBB penetrating anti-inflammatory drugs. In summary, the here presented brain microvessel platform recapitulates physiological properties and allows rapid screening of BBB permeable anti-inflammatory compounds that has been suggested as promising substances to cure so far untreatable neurodegenerative diseases.

cell biology↗