In situ study by immunohistochemistry and immunofluorescence on the biliary tree of normal liver donors confirmed that the hBTSCs residing in the PBG niche constitutively express FasL. Our data suggest that hBTSCs may modulate the T-cells response through the production of FasL that in turn activate the selleck chemicals llc lymphocyte Fas/FasL pathway which induces “premature” apoptosis of CD4+ and CD8+ T-cells. In conclusion, these results disclose an immunomodulatory property of hBTSCs which could have important implications in the regenerative medicine of liver and pancreas and in the
pathogenesis of immune-mediated bile duct diseases, such as primary sclerosing cholangitis. Disclosures: Lola M. Reid – Consulting: PhoenixSongs Biologicals; Grant/Research Support: Vesta Therapeutics, NIH, The Hamner Institute The following people have nothing to disclose: Massimo Riccio, Vincenzo Cardinale, Gianluca Carnevale, Lara Gibellini, Sara De Biasi, Alessandra Pisciotta, Guido Carpino, Raffaele Gentile, Andrea Cossarizza, Eugenio Gaudio, Domenico Alvaro, Anto De Pol Using an established
protocol with modifications, we were able to differentiate both human embryonic and patient-derived induced pluripotent stem selleck kinase inhibitor cells (hESCs and hiPSCs) into hepatocyte-like cells, which functionally resembled primary human hepatocytes. We also showed that these differentiated human hepatocytes (DHHs) old could
be infected in vitro with JFH1-HCVcc and HCV(+) sera of different genotypes. The guestion remains whether it is possible to successfully engraft these cells and establish functional human hepatocytes in vivo. It is known that in vitro hepatic differentiation leads to monolayer of DHHs, which poorly reproduce the 3D architecture of native liver, and may be a reason for the incomplete differentiation of DHHs to mature hepatocytes. In this context, we engrafted, via intrasplenic injection, 2-4 millions DHHs into the liver parenchyma of immune-deficient transgenic mice carrying the urokinase-type plasminogen activator gene driven by the major urinary protein promoter (MUP-uPA/SCID/Bg). Human albumin (hALB) could be detected in the serum of the engrafted mice by ELISA as early as day 10 post-engraftment, with concentrations ranging from 0.4 to 2.3 mg/mL. More importantly, hALB persisted for more than 4 months, consistent with long-term engraftment of human cells in the mouse liver parenchyma. Mice were sacrificed 4 months post-engraftment, and liver sections were assessed by immunostaining for a variety of human proteins (albumin, alpha-1-antitrypsine, alpha-fetoprotein). Areas of human cells were observed around central veins, and could constitute up to 15% of the mouse liver parenchyma.