We subsequently found that in human hepatic stellate cell (HSC) line LX2, CM derived from NASH serum-treated L02 cells considerably increased the expression of fibrosis markers, including α-SMA, COL1A1, COL3A1, and CTGF, and these effects were markedly exacerbated by Ad-shDUSP22, whereas being dramatically mitigated by Ad-DUSP22 (Supplementary Fig. 4p and q). Here, ACTA1 is linked to metabolic dysfunction-associated steatohepatitis.