RESUMO
Recent advances have enabled the direct induction of human tissue-specific stem and progenitor cells from differentiated somatic cells. However, it is not known whether human hepatic progenitor cells (hHepPCs) can be generated from other cell types by direct lineage reprogramming with defined transcription factors. Here, we show that a set of three transcription factors, FOXA3, HNF1A, and HNF6, can induce human umbilical vein endothelial cells to directly acquire the properties of hHepPCs. These induced hHepPCs (hiHepPCs) propagate in long-term monolayer culture and differentiate into functional hepatocytes and cholangiocytes by forming cell aggregates and cystic epithelial spheroids, respectively, under three-dimensional culture conditions. After transplantation, hiHepPC-derived hepatocytes and cholangiocytes reconstitute damaged liver tissues and support hepatic function. The defined transcription factors also induce hiHepPCs from endothelial cells circulating in adult human peripheral blood. These expandable and bipotential hiHepPCs may be useful in the study and treatment of human liver diseases.
Assuntos
Técnicas de Reprogramação Celular/métodos , Células Endoteliais/citologia , Hepatócitos/citologia , Células-Tronco/citologia , Animais , Ductos Biliares/citologia , Ductos Biliares/fisiologia , Agregação Celular , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Células Cultivadas , Reprogramação Celular/genética , Reprogramação Celular/fisiologia , Células Endoteliais/fisiologia , Feminino , Fator 1-alfa Nuclear de Hepatócito/genética , Fator 1-alfa Nuclear de Hepatócito/fisiologia , Fator 3-gama Nuclear de Hepatócito/genética , Fator 3-gama Nuclear de Hepatócito/fisiologia , Fator 6 Nuclear de Hepatócito/genética , Fator 6 Nuclear de Hepatócito/fisiologia , Hepatócitos/fisiologia , Hepatócitos/transplante , Xenoenxertos , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos SCID , Esferoides Celulares/citologia , Esferoides Celulares/fisiologia , Células-Tronco/fisiologiaRESUMO
Angiogenesis is an essential event in the development of synovial inflammation in rheumatoid arthritis (RA). The aim of the current study was to investigate the expression of vasohibin-1, a novel endothelium-derived vascular endothelial growth factor (VEGF)-inducible angiogenesis inhibitor, in the RA synovium, and to test the effect of inflammatory cytokines on the expression of vasohibin-1 by RA synovial fibroblasts (RASFs). Synovial tissue samples were obtained at surgery from patients with osteoarthritis (OA) and RA, and subjected to immunohistochemistry to investigate the expression and distribution of vasohibin-1 relevant to the degree of synovial inflammation. In an in vitro analysis, RASFs were used to examine the expression of vasohibin-1 and VEGF mRNA by real-time PCR after stimulation with VEGF or inflammatory cytokines under normoxic or hypoxic conditions. The immunohistochemical results showed that vasohibin-1 was expressed in synovial lining cells, endothelial cells, and synovial fibroblasts. In synovial tissue, there was a significant correlation between the expression of vasohibin-1 and histological inflammation score (p=0.002, r=0.842). In vitro, stimulation with VEGF induced the expression of vasohibin-1 mRNA in RASFs under normoxic conditions, and stimulation with cytokines induced vasohibin-1 mRNA expression under a hypoxic condition. These results suggest that vasohibin-1 was expressed in RA synovial tissue and might be regulated by inflammatory cytokines.