It was demonstrated that there was a strong induction of tumor-like macrophages and exhaustion of CD8+ T cells (cytotoxic T lymphocytes) in NASH, and Nrg4 knockout mice were shown to exacerbate the deregulation of the hepatic immune microenvironment (Zhang et al., 2022b). Here, NRG4 is linked to metabolic dysfunction-associated steatohepatitis.