18 research outputs found
Assembly and Function of a Bioengineered Human Liver for Transplantation Generated Solely from Induced Pluripotent Stem Cells
The availability of an autologous transplantable auxiliary liver would dramatically affect the treatment of liver disease. Assembly and function in vivo of a bioengineered human liver derived from induced pluripotent stem cells (iPSCs) has not been previously described. By improving methods for liver decellularization, recellularization, and differentiation of different liver cellular lineages of human iPSCs in an organ-like environment, we generated functional engineered human mini livers and performed transplantation in a rat model. Whereas previous studies recellularized liver scaffolds largely with rodent hepatocytes, we repopulated not only the parenchyma with human iPSC-hepatocytes but also the vascular system with human iPS-endothelial cells, and the bile duct network with human iPSC-biliary epithelial cells. The regenerated human iPSC-derived mini liver containing multiple cell types was tested in vivo and remained functional for 4 days after auxiliary liver transplantation in immunocompromised, engineered (IL2rg−/−) rats.Fil: Takeishi, Kazuki. University of Pittsburgh; Estados UnidosFil: Collin de I'Hortet, Alexandra. University of Pittsburgh; Estados UnidosFil: Wang, Yang. University of Pittsburgh; Estados UnidosFil: Handa, Kan. University of Pittsburgh; Estados UnidosFil: Guzman Lepe, Jorge. University of Pittsburgh; Estados UnidosFil: Matsubara, Kentaro. University of Pittsburgh; Estados UnidosFil: Morita, Kazutoyo. University of Pittsburgh; Estados UnidosFil: Jang, Sae. University of Pittsburgh; Estados UnidosFil: Haep, Nils. University of Pittsburgh; Estados UnidosFil: Florentino, Rodrigo M.. University of Pittsburgh; Estados UnidosFil: Yuan, Fangchao. University of Pittsburgh; Estados UnidosFil: Fukumitsu, Ken. University of Pittsburgh; Estados UnidosFil: Tobita, Kimimasa. University of Pittsburgh; Estados UnidosFil: Sun, Wendell. University of Pittsburgh; Estados UnidosFil: Franks, Jonathan. University of Pittsburgh; Estados UnidosFil: Delgado, Evan R.. University of Pittsburgh; Estados UnidosFil: Shapiro, Erik M.. University of Pittsburgh; Estados UnidosFil: Fraunhoffer Navarro, Nicolas Alejandro. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; ArgentinaFil: Duncan, Andrew W.. University of Pittsburgh; Estados UnidosFil: Yagi, Hiroshi. University of Pittsburgh; Estados UnidosFil: Mashimo, Tomoji. University of Pittsburgh; Estados UnidosFil: Fox, Ira J.. University of Pittsburgh; Estados UnidosFil: Soto Gutierrez, Alejandro. University of Pittsburgh; Estados Unido
Cellular Location of HNF4α is Linked With Terminal Liver Failure in Humans
Hepatocyte nuclear factor 4 alpha (HNF4α) is a transcription factor that plays a critical role in hepatocyte function, and HNF4α-based reprogramming corrects terminal liver failure in rats with chronic liver disease. In the livers of patients with advanced cirrhosis, HNF4α RNA expression levels decrease as hepatic function deteriorates, and protein expression is found in the cytoplasm. These findings could explain impaired hepatic function in patients with degenerative liver disease. In this study, we analyzed HNF4α localization and the pathways involved in post-translational modification of HNF4α in human hepatocytes from patients with decompensated liver function. RNA-sequencing analysis revealed that AKT-related pathways, specifically phospho-AKT, is down-regulated in cirrhotic hepatocytes from patients with terminal failure, in whom nuclear levels of HNF4α were significantly reduced, and cytoplasmic expression of HNF4α was increased. cMET was also significantly reduced in failing hepatocytes. Moreover, metabolic profiling showed a glycolytic phenotype in failing human hepatocytes. The contribution of cMET and phospho-AKT to nuclear localization of HNF4α was confirmed using Spearman's rank correlation test and pathway analysis, and further correlated with hepatic dysfunction by principal component analysis. HNF4α acetylation, a posttranslational modification important for nuclear retention, was also significantly reduced in failing human hepatocytes when compared with normal controls. Conclusion: These results suggest that the alterations in the cMET-AKT pathway directly correlate with HNF4α localization and level of hepatocyte dysfunction. This study suggests that manipulation of HNF4α and pathways involved in HNF4α posttranslational modification may restore hepatocyte function in patients with terminal liver failure.Fil: Florentino, Rodrigo M.. Univeristy of Pittsburgh. School of Medicine; Estados Unidos. Universidade Federal de Minas Gerais; BrasilFil: Fraunhoffer Navarro, Nicolas Alejandro. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; ArgentinaFil: Morita, Kazutoyo. University of Pittsburgh at Johnstown; Estados UnidosFil: Takeishi, Kazuki. University of Pittsburgh at Johnstown; Estados UnidosFil: Ostrowska, Alina. University of Pittsburgh at Johnstown; Estados UnidosFil: Achreja, Abhinav. Michigan State University; Estados UnidosFil: Animasahun, Olamide. Michigan State University; Estados UnidosFil: Haep, Nils. University of Pittsburgh at Johnstown; Estados UnidosFil: Arazov, Shohrat. University of Pittsburgh at Johnstown; Estados UnidosFil: Agarwal, Nandini. University of Pittsburgh at Johnstown; Estados UnidosFil: Collin de lHortet, Alexandra. University of Pittsburgh at Johnstown; Estados UnidosFil: Guzman Lepe, Jorge. University of Pittsburgh at Johnstown; Estados UnidosFil: Tafaleng, Edgar N.. University of Pittsburgh at Johnstown; Estados UnidosFil: Mukherjee, Amitava. University of Pittsburgh at Johnstown; Estados UnidosFil: Troy, Kris. University of Pittsburgh at Johnstown; Estados UnidosFil: Banerjee, Swati. University of Pittsburgh at Johnstown; Estados UnidosFil: Paranjpe, Shirish. University of Pittsburgh at Johnstown; Estados UnidosFil: Michalopoulos, George K.. University of Pittsburgh at Johnstown; Estados UnidosFil: Bell, Aaron. University of Pittsburgh at Johnstown; Estados UnidosFil: Nagrath, Deepak. Michigan State University; Estados UnidosFil: Hainer, Sarah J.. University of Pittsburgh at Johnstown; Estados UnidosFil: Fox, Ira J.. University of Pittsburgh at Johnstown; Estados UnidosFil: Soto Gutierrez, Alejandro. University of Pittsburgh at Johnstown; Estados Unido
Expression of SIRT1 in human fetal and adult liver and isolated hepatocytes.
<p>(A) Immunohistochemistry of SIRT1 in human fetal and adult liver, (B) Immunofluorescence staining of SIRT1 in fetal and adult hepatocytes after 2 days of culture. (C) Quantification of hepatic SIRT1 mRNA expression measured by qRT- PCR in human fetal and adult hepatocytes in vitro and in vivo (n≥3/group).</p
Lipids and glucose levels in human fetal hepatocytes after Sirt1 inhibition.
<p>(A) Fluorescent staining of lipids (red droplets, white arrow) inside human fetal hepatocytes (HFH) with or without 50uM Sirtinol for 3 days (20x). (B) Triglycerides quantification of human fetal hepatocytes with or without +50uM Sirtinol for 3 days analyzed by a colorimetric assay. (C) Glucose concentration between normal HFH and HFH +50uM Sirtinol for 3 days. (n≥7/group; *, P < .05).</p
Increased activation of Glucogenesis pathway in human fetal hepatocytes after exposure to Sirtinol.
<p>(A) Expression of hepatic PEPCK and G6PC mRNA measured by qRT- PCR in human fetal hepatocytes exposed to +50uM Sirtinol compared to controls. (B) Immunofluorescence of S-473 AKT in human fetal hepatocytes with or without 50uM Sirtinol (10x). (C) Fluorescence intensity quantification for S-473 AKT signal (arbitrary units) using ImageJ (n≥7/group; *, P < .05). (D) Western blot analysis for S-473 AKT/AKT, S-256 FOXO1/FOXO1 in human fetal hepatocytes exposed to 50uM Sirtinol compared to controls. GAPDH was used as a loading control. (E) Immunofluorescence staining of S-256 FOXO1 in human fetal hepatocytes with or without 50uM Sirtinol (20x).</p