Microstripe pattern substrate consisting of alternating planar and nanoprotrusive regions improved hiPSC-derived cardiomyocytes' unidirectional alignment and functional properties.

The alignment of each cell in human myocardium is considered critical for the efficient movement of cardiac tissue. We investigated 96-well microstripe-patterned plates to align human induced pluripotent stem cell (iPSC)-derived cardiomyocytes (CMs), which resemble fetal myocardium. The aligned CMs (ACMs) cultured on the microstripe-patterned plates exhibited pathology, motor function, gene expression, and drug response that more closely resembled those of adult cells than did unaligned CMs cultured on a flat plate (FCMs). We used these ACMs to evaluate drug side effects and efficacy, and to determine whether these were similar to adult-like responses. When CMs from patients with hypertrophic cardiomyopathy (HCMs) were seeded and cultured on the microstripe-patterned plates or layered on top of the ACMs, both sets of HCMs showed increased heart rate and synchronized contractions, indicating improved cardiac function. It is suggested that the ACMs could be used for drug screening as cells representative of adult-like cardiomyocytes and be transplanted in the form of a cell sheet for regenerative treatment of heart failure.