Periplakin Attenuates Liver Fibrosis via Reprogramming CD44Low Cells into CD44High Liver Progenitor Cells.

BACKGROUND & AIMS: Liver progenitor cells (LPCs) contribute significantly to the restoration of injured liver parenchyma and promote liver regeneration, thereby ameliorating liver fibrosis. However, the mechanism of the derivation of LPCs remains poorly understood.

METHODS

We first examined the expression of periplakin (PPL) in patients and mouse models with liver fibrosis. Adenovirus overexpressing PPL was injected into the tail vein of mouse models to detect the regulatory effect of PPL on liver fibrosis. Single-cell sequencing explored how PPL influences liver fibrosis progression. Additionally, PPL+CD44Low cells and PPL+CD44High LPCs were transplanted into 3,5-diethoxycarbonyl-1,4-dihydrocollidine-induced mouse models to assess their therapeutic efficacy in treating liver fibrosis.

RESULTS

The expression of PPL is upregulated in fibrotic livers in human and mouse models of liver fibrosis. Functionally, we found that PPL overexpression significantly attenuated liver fibrosis. Mechanistically, PPL was specifically expressed in LPCs and promoted LPC expansion. Moreover, we observed that PPL+ cells could be categorized into PPL+CD44Low and PPL+CD44High subsets, and PPL+CD44Low cells were found to redifferentiate into PPL+CD44High LPCs during liver fibrosis. Furthermore, transplantation of PPL+CD44High LPCs notably suppressed liver fibrosis.

CONCLUSIONS

These findings demonstrate that PPL+CD44Low cells can be reprogrammed into PPL+CD44High LPCs, which ameliorate liver fibrosis, suggesting a potential application of PPL for the treatment of liver fibrosis.