JAG1 and Jaundice: From an experimental point of view, TAGLN-Cre-mediated JAGGED1 deletion in portal mesenchymal cells caused significant jaundice [3], suggesting that portal mesenchymal cells express JAGGED1 to induce epithelial differentiation that occurs in their periphery between mouse embryonic Days 13.5 (E13.5) and E18.5 [5].