RESUMO
Hepatocytes play important roles in the liver, but in culture, they immediately lose function and dedifferentiate into progenitor-like cells. Although this unique feature is well-known, the dynamics and mechanisms of hepatocyte dedifferentiation and the differentiation potential of dedifferentiated hepatocytes (dediHeps) require further investigation. Here, we employ a culture system specifically established for hepatic progenitor cells to study hepatocyte dedifferentiation. We found that hepatocytes dedifferentiate with a hybrid epithelial/mesenchymal phenotype, which is required for the induction and maintenance of dediHeps, and exhibit Vimentin-dependent propagation, upon inhibition of the Hippo signaling pathway. The dediHeps re-differentiate into mature hepatocytes by forming aggregates, enabling reconstitution of hepatic tissues in vivo. Moreover, dediHeps have an unexpected differentiation potential into intestinal epithelial cells that can form organoids in three-dimensional culture and reconstitute colonic epithelia after transplantation. This remarkable plasticity will be useful in the study and treatment of intestinal metaplasia and related diseases in the liver.
Assuntos
Desdiferenciação Celular , Diferenciação Celular , Células Epiteliais , Hepatócitos , Animais , Hepatócitos/citologia , Hepatócitos/metabolismo , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Camundongos , Organoides/citologia , Organoides/metabolismo , Transição Epitelial-Mesenquimal , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Células Cultivadas , Transdução de Sinais , Vimentina/metabolismo , Via de Sinalização Hippo , Fígado/citologia , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Masculino , Técnicas de Cultura de Células/métodosRESUMO
Shiga toxin (Stx) exerts toxic activity by binding to glycosphingolipids, mainly globotriaosyl (Gb(3)) ceramide, on the surface of target cells. The inhibition of toxin-receptor binding is a promising therapeutic approach to prevent Stx-mediated diseases. In this study, we synthesized monovalent Stx-ligands of phosphatidylethanolamine dipalmitoyl-Gb(3) (Gb(3)-PEDP) and galabiosyl (Gb(2))-PEDP and we examined their neutralizing activity against Stx-1 and Stx-2 in vitro. Both Gb(3)-PEDP and Gb(2)-PEDP strongly neutralized the cytotoxicity of Stx-1 and Stx-2. It is likely that the mechanism of neutralization involved formation of liposomes and consequently clustering of sugar units. We propose monovalent Gb(3)-/Gb(2)-derivatives conjugated with phosphatidyl residue as a novel class of Stx-neutralizing agent.