In order for medications to be approved by the FDA, they must be vetted to make sure they do not pose a danger to the heart or any other part of the body. In the earliest phases of testing, cells are treated with the medication to see how they react. Traditionally, the most reliable method is to measure their response manually, by directly sticking probes into the cell. New high-throughput technologies speed up this practice. However, until now no such high-throughput system has been available for work with actual heart cells.
In the newly developed system published in the journal Nature Communications, the research team used light to both make the cardiac cells beat and to optically measure their response. This allowed them to automate the drug-testing process, offering a fast, new way to rule out potentially dangerous drugs.
The technique streamlines a primarily manual process that researchers carry out to comply with FDA testing requirements and ensure the safety of the drugs. The team's current system can test 30,000 light-responsive cells in fewer than 10 minutes - a far shorter timeline than the standard practice, which can take hours or even years.
Authors validate optical actuation by virally introducing optogenetic drivers in rat and human cardiomyocytes or through the modular use of dedicated light-sensitive somatic ‘spark’ cells. We show that this automated all-optical approach provides HT means of cellular interrogation, that is, allows for dynamic testing of >600 multicellular samples or compounds per hour, and yields high-content information about the action of a drug over time, space and doses.
"The benefit of optical stimulation and optical recording is that it provides a way to dynamically control millions of cells simultaneously without needing to come into contact with the sample," said first author on the paper. "This not only allows you to perform faster testing but also provides a safer way to do measurements if you're testing hazardous materials."