Cell surface PD-L1 expression of activated intrahepatic
MPs decreased by ex vivo TAF treatment
We established an animal TAA-induced liver injury model to identify theex vivo TAF effects on inflamed intrahepatic MPs. TAA was
injected intraperitoneally for 8 weeks (Fig 4A). H&E staining of
paraffin-embedded liver sections showed that hepatocyte necrosis and
sinusoidal congestion were significantly higher in the TAA-treated
group’s livers than in those of the no TAA-treated ones. Sirius red
staining showed that the collagen deposition area was increased in the
TAA-treated group’s livers compared to that in the no TAA-treated group
(Fig 4B). The TAA-treated injured livers were perfused with collagenase,
and MPs were isolated using gradient centrifugation. The isolated MPs
were treated with different TAF concentrations (Fig 4C). TAF- or
mock-treated MPs were analysed using flow cytometry. The number of
PD-L1+ cells among the total analysed MPs was
decreased by TAF in a concentration-dependent manner (Fig 4D). TAF
treatment decreased the MFI of PD-L1 in
CD11b+F4/80+ intrahepatic MPs (Fig
4E).