To determine whether macrophages release factors that activate HSCs during NASH fibrosis, we found that Havcr2 knockdown significantly reduced TGF-β but not PDGFβ or Ccl2 in macrophages (Fig. 5N), suggesting that TGF-β may be involved in HSC activation and NASH fibrosis. Here, PDGFB is linked to metabolic dysfunction-associated steatohepatitis.