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It is well known that immune-mediated virus elimination is necessary for the treatment of HBV infection. Reconstitution of human immune cells in liver chimeric mice is warranted to understand the immunopathogenesis of HBV infection. Here, we report a new immunologically humanized mouse model with a human immune system via reconstitution of immunodeficient NOG-Iaß/ß2 m double KO mice, which are NOG mice that are deficient in both MHC class I and II (DKO-NOG mice), with human HLA-A2-positive peripheral blood mononuclear cells (PBMCs). After injection of PBMCs, the xenogeneic graft-versus-host disease observed in PBMC-engrafted NOG mice was prevented in PBMC-engrafted DKO-NOG mice. Liver damage was reduced, and the survival time was prolonged in human PBMC-engrafted DKO-NOG mice compared to those in the NOG mice. The expression levels of PD-1 and Tim-3 on human T cells from PBMC-engrafted DKO-NOG mice were lower than those from NOG mice. By induction of HBV-specific T cell responses, such as vaccination with HBc-derived, peptide-pulsed DCs, hydrodynamic injection of HBV vector and intrasplenic injection of HepG2.2.15, the number of HBc-derived, peptide-specific CTLs increased in PBMC-engrafted DKO-NOG mice. Moreover, the recombinant HBV vaccine resulted in the production of hepatitis B surface antibody in 50% of the vaccinated mice. The induction of HBV-specific immune responses could be established in the immunologically humanized mice.

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Natural killer (NK) cell activation is associated with both liver injury and persistent infection in chronic hepatitis C (CHC); however, the detailed mechanism of this activation has not yet been fully elucidated. Because galectin-9 (Gal-9) has been reported to be increased in the serum and liver tissue of CHC patients, we investigated the function of Gal-9 in NK cell activation in CHC. First, we evaluated the function of Gal-9 on NK cytotoxicity in vitro. Gal-9 treatment resulted in increased cytotoxicity of naïve NK cells, and the Gal-9-activated NK cells demonstrated cytotoxicity toward hepatoma cells and T cells. Additionally, coculturing peripheral blood mononuclear cells (PBMCs) with JFH-1/Huh7.5.1 cells increased both Gal-9 production and NK cell cytotoxicity. Next, we investigated the source of Gal-9 and the mechanism of Gal-9 production. Deletion of CD14+ monocytes from PBMCs resulted in reduced Gal-9 production in the coculture with JFH-1/Huh7.5.1 cells. Gal-9 production was driven by coculturing of PBMCs with apoptotic hepatocytes. Blocking integrin αv ß3 , a receptor for phosphatidylserine expressed on apoptotic cells, also resulted in decreased Gal-9 production. Finally, we found that serum Gal-9 levels were significantly higher in CHC patients than in healthy donors and patients who achieved sustained virologic response. Among CHC patients, serum Gal-9 levels were significantly higher in patients with elevated alanine aminotransferase (ALT) than in those with normal ALT. CONCLUSION: These results demonstrate that CD14+ monocyte-derived Gal-9 increases NK cell cytotoxicity in HCV infection, which might be associated with liver injury and persistent infection. (Hepatology 2017;65:18-31).

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α-Galactosylceramide (α-GalCer) has been reported to be therapeutic against metastatic liver tumors in mice. However, little is known regarding the efficacy of combined chemo-immunotherapy using α-GalCer and anticancer drugs. In this study, we evaluated the antitumor effect of the combination therapy of α-GalCer and 5-fluorouracil (5-FU) against liver tumors of MC38 colon cancer cells. The liver weights of tumor-bearing mice treated with the combination were significantly lower than those of nontreated mice and of mice treated with 5-FU or α-GalCer alone. No toxic effects on the liver and renal functions were observed in any of the treatment groups. α-GalCer treatment induced significant activation of liver NK cells in vivo, but 5-FU treatment did not. 5-FU treatment resulted in a significant upregulation of NKG2D activating molecules (Rae-1 and H60) and DNAM-1 ligands (CD112 and CD155) on MC38 cells, but α-GalCer did not. The cytolytic activity of α-GalCer-activated liver mononuclear cells against 5-FU-treated MC38 cells was significantly higher than that against nontreated cells. The increase of the cytolytic activity induced by 5-FU partially depended on NKG2D-Rae-1 or H60 signals. Depletion of NK cells significantly inhibited the antitumor efficacy of 5-FU against MC38 liver tumors, which suggested that the antitumor effect of 5-FU partially depended on the cytolytic activity of NK cells. These results demonstrated that the combination therapy of α-GalCer and 5-FU produced synergistic antitumor effects against liver tumors by increasing the expression of NK activating molecules on cancer cells. This study suggests a promising new chemo-immunotherapy against metastatic liver cancer.

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The production of soluble major histocompatibility complex class I-related chain A (MICA) is thought to antagonize NKG2D-mediated immunosurveillance. Interleukin-1ß (IL-1ß) is elevated in patients with chronic hepatitis C (CH), and this might contribute to the escape of hepatocellular carcinoma (HCC) cells from innate immunity. In this study, we investigated the immunoregulatory role of IL-1ß in the production of soluble MICA of HCC cells. First, we investigated the correlation between the serum IL-1ß levels and soluble MICA in CH patients. Serum IL-1ß levels were associated with soluble MICA levels in CH patients. The serum IL-1ß levels of CH patients with the HCC occurrence were significantly higher than those of CH patients without HCC. We next examined the MICA production of IL-1ß-treated HCC cells. Addition of IL-1ß resulted in significant increase in the production of soluble MICA in HepG2 and PLC/PRF/5 cells, human HCC cells. But soluble MICA was not detected in both non-treated and IL-1ß-treated normal hepatocytes. Addition of IL-1ß did not increase the expressions of membrane-bound MICA on HCC cells. These were observed similarly in various cancer cells including a gastric cancer (MKN1), two colon cancers (HCT116 and HT29) and a cervical cancer (HeLa). Addition of IL-1ß also increased the expression of a disintegrin and metalloproteinase (ADAM)9 in HCC cells, and the knockdown of ADAM9 in IL-1ß-treated HCC cells resulted in the decrease in the production of soluble MICA of HCC cells. These findings indicate that IL-1ß might enhance the production of soluble MICA by activating ADAM9 in human HCC.

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A novel hetrotrinuclear complex composed of two ferrocenium-ion moieties and copper complex of 2-aminotropones showed relatively strong intramolecular ferromagnetic coupling in the solid states owing to spin polarization mechanism.