Single cell RNA-sequencing of iPS cells derived multicellular human liver organoids

By taking advantage of the foregut generation method, we initially differentiated iPSCs to foregut spheroids through definitive endoderm specification as described. The foregut spheroids were embedded in Matrigel and cultured with retinoic acid (RA). Following 4-day RA treatment, we switched into hepatocyte maturation media for the induction of the hepatocyte differentiation process to establish human liver organoids, hereafter defined as HLO, as early as day 20. To gain quantitative insights regarding the cellular composition in HLO, single-cell RNA sequencing was used to analyze their mRNA expression from 4,059 cells. t-distributed stochastic neighbor embedding analysis confirmed the five distinct major clusters among the cells in HLO, containing hepatocyte-, biliary cell-, hepatic stellate cell-, Kupffer cell-, biliary tree (or peribiliary gland) stem cell-like populations. Overall design: Examination of mRNA expression profile at single cell level in multicellular human liver organoids