Lipoprotein profile and lipid metabolism of PXB-cells®, human primary hepatocytes from liver-humanized mice: proposal of novel in vitro system for screening anti-lipidemic drugs

Biomed Res. 2020;41(1):33-42. doi: 10.2220/biomedres.41.33.


We investigated lipid metabolism in PXB-cells, which are human primary hepatocytes isolated from liver-humanized mice, and HepG2 and HuH-7 human hepatoma cell lines. Lipoprotein levels were higher in PXB-cells than in the 2 other cell lines, and PXB-cells mainly released triglycerides and cholesterol as very low density lipoprotein (VLDL), similar to actual liver tissue, whereas the major lipoprotein released from the 2 hepatoma cell lines was LDL. RT-PCR analysis demonstrated that the gene expression levels of apolipoprotein B100 (ApoB100), the apolipoprotein of VLDL/LDL, were similar in PXB-cells and HepG2 cells, while the overexpression of ApoC2, ApoC3, and ApoE, which are components of VLDL, but not LDL, was observed in PXBcells. A protein immunoassay revealed that ApoB100 levels secreted from PXB-cells and HuH-7 cells were similar; however, ApoC3 levels were higher in PXB-cells than in the two other cell lines. We also examined the anti-lipidemic activities of fenofibrate using this assay system. Fenofibrate suppressed lipoprotein production from PXB-cells in a dose-dependent manner mainly by activating the β-oxidation pathway. These results suggest that PXB-cells produce high levels of lipoproteins and are suitable for screening anti-lipidemic agents.

MeSH terms

  • Animals
  • Apolipoprotein B-100 / metabolism
  • Carcinoma, Hepatocellular / metabolism
  • Cell Line, Tumor
  • Fenofibrate / pharmacology*
  • Hep G2 Cells
  • Hepatocytes
  • Humans
  • Lipid Metabolism*
  • Lipoproteins / metabolism*
  • Lipoproteins, VLDL / metabolism
  • Liver / metabolism
  • Liver / pathology
  • Liver Neoplasms / metabolism
  • Mice
  • Mice, SCID
  • Oxygen / chemistry
  • Time Factors
  • Triglycerides / metabolism


  • Apolipoprotein B-100
  • Lipoproteins
  • Lipoproteins, VLDL
  • Triglycerides
  • Oxygen
  • Fenofibrate