Dataset Information

The reconstituted 'humanized liver' in TK-NOG mice is mature and functional.

ABSTRACT: To overcome the limitations of existing models, we developed a novel experimental in vivo platform for replacing mouse liver with functioning human liver tissue. To do this, a herpes simplex virus type 1 thymidine kinase (HSVtk) transgene was expressed within the liver of highly immunodeficient NOG mice (TK-NOG). Mouse liver cells expressing this transgene were ablated after a brief exposure to a non-toxic dose of ganciclovir (GCV), and transplanted human liver cells are stably maintained within the liver (humanized TK-NOG) without exogenous drug. The reconstituted liver was shown to be a mature and functioning "human organ" that had zonal position-specific enzyme expression and a global gene expression pattern representative of mature human liver; and could generate a human-specific profile of drug metabolism. The 'humanized liver' could be stably maintained in these mice with a high level of synthetic function for a prolonged period (8 months). This novel in vivo system provides an optimized platform for studying human liver physiology, including drug metabolism, toxicology, or liver regeneration.

SUBMITTER: Hasegawa M

PROVIDER: S-EPMC3648850 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

The reconstituted 'humanized liver' in TK-NOG mice is mature and functional.

Hasegawa Masami M Kawai Kenji K Mitsui Tetsuya T Taniguchi Kenji K Monnai Makoto M Wakui Masatoshi M Ito Mamoru M Suematsu Makoto M Peltz Gary G Nakamura Masato M Suemizu Hiroshi H

Biochemical and biophysical research communications 20110114 3

To overcome the limitations of existing models, we developed a novel experimental in vivo platform for replacing mouse liver with functioning human liver tissue. To do this, a herpes simplex virus type 1 thymidine kinase (HSVtk) transgene was expressed within the liver of highly immunodeficient NOG mice (TK-NOG). Mouse liver cells expressing this transgene were ablated after a brief exposure to a non-toxic dose of ganciclovir (GCV), and transplanted human liver cells are stably maintained within ...[more]

PMID: 21238430

Similar Datasets

Project description:UnlabelledHepatitis B virus (HBV)-specific cytotoxic T lymphocytes (CTLs) are critical in eliminating infection. We developed an animal model in which HBV-infected human hepatocytes are targeted by HBV-specific CTLs. After HBV inoculation in human hepatocyte-transplanted herpes simplex virus type-1 thymidine kinase-NOG mice, human peripheral blood mononuclear cells (PBMCs) were administered, and albumin, HBV DNA, alanine aminotransferase (ALT), and cytokine levels were analyzed. Histopathological and flow-cytometric analysis of infiltrating human immune cells were performed, and the efficacy of CTL-associated antigen-4 immunoglobulin (CTLA4Ig) against liver damage was evaluated. PBMC treatment resulted in massive hepatocyte damage with elevation of ALT, granzyme A, and gamma interferon and decrease in albumin and HBV DNA. The number of liver-infiltrating human lymphocytes and CD8-positive cells was significantly higher in HBV-infected mice. HBV-specific CTLs were detected by core and polymerase peptide-major histocompatibility complex-tetramer, and the population of regulatory T cells was significantly decreased in HBV-infected mice. Serum hepatitis B surface (HBs) antigen became negative, and HBs antibody appeared. CTLA4Ig treatment strongly inhibited infiltration of mononuclear cells. CTLA4Ig treatment will be used to treat patients who develop severe acute hepatitis B to prevent liver transplantation or lethality. This animal model is useful for virological and immunological analysis of HBV infection and to develop new therapies for severe acute hepatitis B.ImportanceWithout liver transplantation, some HBV-infected patients will die from severe liver damage due to acute overreaction of the immune system. No effective treatment exists, due in part to the lack of a suitable animal model. An animal model is necessary to investigate the mechanism of hepatitis and to develop therapeutic strategies to prevent acute liver failure in HBV infection. We developed an animal model in which HBV-infected human hepatocytes are targeted by human HBV-specific CTLs. In this model, HBV-infected human hepatocytes were transplanted into severely immunodeficient NOG mice in order to reconstruct elements of the human immune system. Using this model, we found that CTL-associated antigen-4 immunoglobulin was able to suppress damage to HBV-infected hepatocytes, suggesting an approach to treatment. This animal model is useful for virological and immunological analysis of HBV infection and to develop new therapies for severe acute hepatitis B.

Project description:BackgroundSeven of 15 clinical trial participants treated with a nucleoside analogue (fialuridine [FIAU]) developed acute liver failure. Five treated participants died, and two required a liver transplant. Preclinical toxicology studies in mice, rats, dogs, and primates did not provide any indication that FIAU would be hepatotoxic in humans. Therefore, we investigated whether FIAU-induced liver toxicity could be detected in chimeric TK-NOG mice with humanized livers.Methods and findingsControl and chimeric TK-NOG mice with humanized livers were treated orally with FIAU 400, 100, 25, or 2.5 mg/kg/d. The response to drug treatment was evaluated by measuring plasma lactate and liver enzymes, by assessing liver histology, and by electron microscopy. After treatment with FIAU 400 mg/kg/d for 4 d, chimeric mice developed clinical and serologic evidence of liver failure and lactic acidosis. Analysis of liver tissue revealed steatosis in regions with human, but not mouse, hepatocytes. Electron micrographs revealed lipid and mitochondrial abnormalities in the human hepatocytes in FIAU-treated chimeric mice. Dose-dependent liver toxicity was detected in chimeric mice treated with FIAU 100, 25, or 2.5 mg/kg/d for 14 d. Liver toxicity did not develop in control mice that were treated with the same FIAU doses for 14 d. In contrast, treatment with another nucleotide analogue (sofosbuvir 440 or 44 mg/kg/d po) for 14 d, which did not cause liver toxicity in human trial participants, did not cause liver toxicity in mice with humanized livers.ConclusionsFIAU-induced liver toxicity could be readily detected using chimeric TK-NOG mice with humanized livers, even when the mice were treated with a FIAU dose that was only 10-fold above the dose used in human participants. The clinical features, laboratory abnormalities, liver histology, and ultra-structural changes observed in FIAU-treated chimeric mice mirrored those of FIAU-treated human participants. The use of chimeric mice in preclinical toxicology studies could improve the safety of candidate medications selected for testing in human participants. Please see later in the article for the Editors' Summary.

Dataset Information

The reconstituted 'humanized liver' in TK-NOG mice is mature and functional.

Publications

The reconstituted 'humanized liver' in TK-NOG mice is mature and functional.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets