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Biology subjects

Gil, D. A.

Publications and source records attributed to Gil, D. A..

2 recordsLinked to original sources
bioRxiv2020

Patient-derived cancer organoid tracking with widefield one-photon redox imaging to assess treatment response

MotivationAccessible tools are needed for rapid, non-destructive imaging of patient-derived cancer organoid (PCO) treatment response to accelerate drug discovery and streamline treatment planning for individual patients. AimSegment and track individual PCOs with widefield one-photon redox imaging to extract morphological and metabolic variables of treatment response. ApproachRedox imaging of the endogenous fluorophores, NAD(P)H and FAD, was used to monitor the metabolic state and morphology of PCOs. Redox imaging was performed on a widefield one-photon epifluorescence microscope to evaluate drug response in two colorectal PCO lines. An automated image analysis framework was developed to track PCOs across multiple time points over 48 hours. Variables quantified for each PCO captured metabolic and morphological response to drug treatment, including the optical redox ratio and organoid area. ResultsThe optical redox ratio (NAD(P)H/(FAD+NAD(P)H)) was independent of PCO morphology pre-tieatment. Drugs that induced cell death decreased the optical redox ratio and growth rate compared to control. Multivariate analysis of redox and morphology variables identified distinct PCO sub-populations. Single-organoid tracking improved sensitivity to drug treatment compared to pooled organoid analysis. ConclusionWidefield one-photon redox imaging can monitor metabolic and morphological changes on a single organoid-level, providing an accessible, non-destructive tool to screen drugs in patient-matched samples.

bioengineering↗
bioRxiv2020

Adaptable pulsatile flow generated by quantitative imaging of stem-cell derived cardiomyocytes for disease modeling

Endothelial cells (EC) in vivo are continuously exposed to a mechanical microenvironment from blood flow, and fluidic shear stress plays an important role in EC behavior. New approaches to generate physiologically and pathologically relevant pulsatile flows are needed to understand EC behavior under different shear stress regimes. Here, we demonstrate an adaptable pump (Adapt-Pump) platform for generating pulsatile flows via quantitative imaging of human pluripotent stem cell-derived cardiac spheroids (CS). Pulsatile flows generated from the Adapt-Pump system can recapitulate unique CS contraction characteristics, accurately model responses to clinically relevant drugs, and simulate CS contraction changes in response to fluidic mechanical stimulation. We discovered that ECs differentiated under a long QT syndrome derived pathological pulsatile flow exhibit abnormal EC monolayer organization. This Adapt-Pump platform provides a powerful tool for modeling the cardiovascular system and improving our understanding of EC behavior under different mechanical microenvironments.

bioengineering↗