Functional human hepatocytes xenografted into the liver of mice can be used as a model system to study pharmacokinetics,infection of hepatitis viruses,and the efficacy of hepatitis vaccines.Significant levels of liver xeno-repopulation have been reported in Fah-/-Rag2-/-Il2rg-/-mice.However,the high mortality and low breeding rate of this model may hinder its application.A new model,termed Fah-/-Nod/Scid mice,which combines the advantages of liver repopulation in Fah-/-mice with the ease of xenotransplantation in Nod/Scid mice was obtained by gradual cross-breeding.Fah-/-Nod/Scid mice were easily maintained in breeding colonies and in adult animal care facilities.FK506 treatment combined with gradual withdrawal of NTBC before cell transplantation ensured that Fah-/-Nod/Scid mice were susceptible to liver xeno-repopulation by human hepatocytes;the proportion of engrafted human hepatocytes reached 33.6%.The function of the expanded human hepatocytes within the chimeric liver was confirmed by weight curve analysis,the expression of characteristic proteins,and the biochemical analysis of liver function.These results show that Fah-/-Nod/Scid mice are an ideal humanized liver mouse model with many useful applications.
Neuroplastin 65(Np65) is an immunoglobulin superfamily cell adhesion molecule involved in synaptic formation and plasticity. Our recent study showed that Np65-knockout(KO) mice exhibit abnormal cognition and emotional disorders. However, the underlying mechanisms remain unclear. In this study, we found 588 differentiallyexpressed genes in Np65-KO mice by microarray analysis.RT-PCR analysis also revealed the altered expression of genes associated with development and synaptic structure,such as Cdh1, Htr3 a, and Kcnj9. In addition, the expression of Wnt-3, a Wnt protein involved in development, was decreased in Np65-KO mice as evidenced by western blotting. Surprisingly, MRI and DAPI staining showed a significant reduction in the lateral ventricular volume of Np65-KO mice. Together, these findings suggest that ablation of Np65 influences gene expression, which may contribute to abnormal brain development. These results provide clues to the mechanisms underlying the altered brain functions of Np65-deficient mice.
