In cardiac tissue engineering approaches to treat myocardial infarction, cardiac cells
are seeded within three-dimensional porous scaffolds to create functional
cardiac patches. However, current cardiac patches do not allow for online
monitoring and reporting of engineered-tissue performance, and do not interfere
to deliver signals for patch activation or to enable its integration with the
host. Here, we report an engineered cardiac patch that integrates cardiac cells
with flexible, free-standing electronics and a 3D nanocomposite scaffold. The
patch exhibited robust electronic properties, enabling the recording of cellular
electrical activities and the on-demand provision of electrical stimulation for
synchronizing cell contraction. We also show that electroactive polymers
containing biological factors can be deposited on designated electrodes to
release drugs in the patch microenvironment on-demand. We expect that the
integration of complex electronics within cardiac patches will eventually
provide therapeutic control and regulation of cardiac function.
Fig. S1: Epithelial cells are viable on continuous carbon films and EM grids. Left: 10x phase micrograph of MDCKII cells on untreated continuous carbon film. Right: Lifeact GFP MDCKII cells plated on EM grids treated with fibronectin, imaged at 10x GFP.
Cryo-electron tomography is the highest resolution tool available for structural analysis of macromolecular complexes within their native cellular environment. At present, data acquisition suffers from low throughput, in part due to the low probability of positioning a cell such that the subcellular structure of interest is on a region of the electron microscopy (EM) grid that is suitable for imaging. Here, we leverage photo-micropatterning of EM grids to optimally position endothelial cells to enable high-throughput imaging of cell-cell contacts. This method increases the distance between contacts and the thicker cell nuclei such that the regions of interest are sufficiently thin for imaging. The resulting pipeline enables the observation of a diverse array of structures at endothelial cell-cell contacts, demonstrating the utility of this technique in enhancing the rate of data acquisition for cellular cryo-electron tomography studies.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.