Fig. 1

Generation and validation of human pluripotent stem cell-derived chambered cardiac organoids. A Schematic of the established hPSC-CM differentiation protocol. B RT-PCR tracking of relevant markers of cardiomyocyte differentiation from day 0 to day 9. C Schematic of the altered differentiation protocol to generate cardiac organoids. D Representative brightfield images of CCOs generated using 300k, 400k or 500k cells from day 8 to day 17. E Percentage of CCOs generated using 300k, 400k or 500k cells per organoid (n = 8 organoids per group from 3 experiments; mean ± s.d; *P = 0.0141; two-tailed Student’s t test). F Confocal immunofluorescence image of cardiomyocyte marker cTnT (green), smooth muscle cell marker SMMHC (green), proliferation marker Ki67 (red) and apoptosis marker cleaved Caspase-3 (red) in day 21 organoids generated from 300k, 400k or 500k cells. Cryosections were co-stained with DAPI (blue). Scale bar, 100 µm