Abstract
Human iPS-derived cardiomyocyte (iPS-CM) is potential source for the development of toxicity assay systems to predict the cardiac adverse event in clinical usage. Actually, electrophysiological assessment with multi-electrode array system showed excellent correlations between field potential duration and QTc prolongation. In the present study, we would like to introduce new multi-spheroid imaging analysis by Cellvoyager CV7000 system. This assay system brought unique parameters and they would be a suitable for in vitro screening to assess cardiotoxicity of drugs at an early stage of drug development process.
In briefly, iPS-CM (iCell® Cardiomyocytes) was seeded into Cell-ableTM plate which has multiple fibronectin-coated spots in each well (40-400 spots/well) and spheroids were formed on all spots after 7 days culture. Then, the spheroids were incubated with several test compounds and calcium (Ca) sensing fluorescence dye was added for measurement of change in intracellular Ca concentrations. The changes in fluorescent intensity of all spheroids were detected using Cellvoyager CV7000 system.
For optimization, the size of iPS-CM spheroid was modified by changing of diameter of fibronection spot. The result showed that diameter of around 100 µm is suitable for iPS-CM spontaneous beating. Seeded iPS-CM cells numbers were adjusted for optimizing cubic volume of spheroid. Optimized condition and the results after anti-cancer agent treatment in multi-spheroid imaging analysis will be introduced in JSOT annual meeting.
