Allelic regulation of CK19 during maturation of pancreatic ductal cells

Human pluripotent stem cells have a tremendous potential to study development and disease in vitro and can be used as a model for all kinds of human tissues and organs when differentiated into specific cell types. In this study a CK19-mCherry reporter human embryonic stem cell line was generated and used to investigate the role and expression pattern of CK19 during pancreatic development and differentiation. Using the CRISPR-Cas9 technique, the mCherry gene was integrated into one CK19 allele, rendering a heterozygous reporter of endogenous CK19 expression. Interestingly, the reporter revealed that ductal marker CK19 is already expressed at very early stages in development, being observed as early as definitive endoderm stage. Expression further increased when cells were differentiated into pancreatic progenitor cells, with all successfully differentiated cells showing mCherry expression. Intriguingly, a shift from biallelic to monoallelic expression was observed upon further maturation towards fully mature pancreatic ductal cells, resulting in only 50 % of cherry positive cells at d27 of the differentiation, even though all cells stained positive for CK19. These results indicate that allelic regulation of CK19 might be an important factor in the differentiation and maturation of pancreatic exocrine cells and that the gene could play a role in earlier developmental stages then previously suspected.

Publication History

Article published online:
07 September 2021