Analysis of Hepatitis C Virus Particle Heterogeneity in Immunodeficient Human Liver Chimeric Mice.

Background & Aims: Hepatitis C virus (HCV) is a leading cause of chronic liver diseases and the most common indication for liver transplantation in the United States. HCV particles in the blood of infected patients are characterized by heterogeneous buoyant densities, likely owing to HCV association with lipoproteins. However, clinical isolates are not infectious in vitro and the relative infectivity of the particles with respect to their buoyant density therefore cannot be determined, pointing to the need for better in vivo model systems.

In situ expansion of engineered human liver tissue in a mouse model of chronic liver disease.

Control of both tissue architecture and scale is a fundamental translational roadblock in tissue engineering. An experimental framework that enables investigation into how architecture and scaling may be coupled is needed. We fabricated a structurally organized engineered tissue unit that expanded in response to regenerative cues after implantation into mice with liver injury.

Mouse models of acute and chronic hepacivirus infection.

An estimated 71 million people worldwide are infected with hepatitis C virus (HCV). The lack of small-animal models has impeded studies of antiviral immune mechanisms. Here we show that an HCV-related hepacivirus discovered in Norway rats can establish high-titer hepatotropic infections in laboratory mice with immunological features resembling those seen in human viral hepatitis.

Acrylamide-induced Subacute Neurotoxic Effects on the Cerebral Cortex and Cerebellum at the Synapse Level in Rats.

Objective: To investigate acrylamide (ACR)-induced subacute neurotoxic effects on the central nervous system (CNS) at the synapse level in rats.

Methods: Thirty-six Sprague Dawley (SD) rats were randomized into three groups, (1) a 30 mg/kg ACR-treated group, (2) a 50 mg/kg ACR-treated group, and (3) a normal saline (NS)-treated control group. Body weight and neurological changes were recorded each day.

Interferon regulatory factor 2 protects mice from lethal viral neuroinvasion.

The host responds to virus infection by activating type I interferon (IFN) signaling leading to expression of IFN-stimulated genes (ISGs). Dysregulation of the IFN response results in inflammatory diseases and chronic infections. In this study, we demonstrate that IFN regulatory factor 2 (IRF2), an ISG and a negative regulator of IFN signaling, influences alphavirus neuroinvasion and pathogenesis.

Humanized mice efficiently engrafted with fetal hepatoblasts and syngeneic immune cells develop human monocytes and NK cells.

Background & Aims: Human liver chimeric mice are useful models of human hepatitis virus infection, including hepatitis B and C virus infections. Independently, immunodeficient mice reconstituted with CD34(+) hematopoietic stem cells (HSC) derived from fetal liver reliably develop human T and B lymphocytes. Combining these systems has long been hampered by inefficient liver reconstitution of human fetal hepatoblasts.

Superior In vivo Transduction of Human Hepatocytes Using Engineered AAV3 Capsid.

Adeno-associated viral (AAV) vectors are currently being tested in multiple clinical trials for liver-directed gene transfer to treat the bleeding disorders hemophilia A and B and metabolic disorders. The optimal viral capsid for transduction of human hepatocytes has been under active investigation, but results across various models are inconsistent. We tested in vivo transduction in "humanized" mice.

Hepatitis C virus infects rhesus macaque hepatocytes and simianized mice.

Unlabelled: At least 170 million people are chronically infected with hepatitis C virus (HCV). Owing to the narrow host range of HCV and restricted use of chimpanzees, there is currently no suitable animal model for HCV pathogenesis studies or the development of a HCV vaccine. To identify cellular determinants of interspecies transmission and establish a novel immunocompetent model system, we examined the ability of HCV to infect hepatocytes from a small nonhuman primate, the rhesus macaque (Macaca mulatta).

A serpin shapes the extracellular environment to prevent influenza A virus maturation.

Interferon-stimulated genes (ISGs) act in concert to provide a tight barrier against viruses. Recent studies have shed light on the contribution of individual ISG effectors to the antiviral state, but most have examined those acting on early, intracellular stages of the viral life cycle. Here, we applied an image-based screen to identify ISGs inhibiting late stages of influenza A virus (IAV) infection.

Broadly neutralizing antibodies abrogate established hepatitis C virus infection.

In most exposed individuals, hepatitis C virus (HCV) establishes a chronic infection; this long-term infection in turn contributes to the development of liver diseases such as cirrhosis and hepatocellular carcinoma. The role of antibodies directed against HCV in disease progression is poorly understood. Neutralizing antibodies (nAbs) can prevent HCV infection in vitro and in animal models.

Insufficient interleukin-12 signalling favours differentiation of human CD4(+) and CD8(+) T cells into GATA-3(+) and GATA-3(+) T-bet(+) subsets in humanized mice.

Differentiation of CD4(+) T cells into type 1 or type 2 subsets is mediated by the expression of the opposing lineage defining transcription factors T-bet and GATA-3. However, the existence of GATA-3(+) T-bet(+) CD4(+) T cells in mice suggests functional plasticity of these subsets. Little is known about type 1 and type 2 plasticity of human T-cell subsets in vivo.