In addition to the rapid response to reinfection (245), Koda and colleagues demonstrated that in High-fat and high-cholesterol (HFHC), diet-induced model of Non-alcoholic steatohepatitis (NASH), resident memory CD8+ T lymphocytes are maintained by the cytokine IL-15 locally produced, and induce apoptosis of hepatic stellate cells (HSCs) via Fas-FasL, restoring tissue homeostasis and preventing HSC-mediated fibrosis (246). This evidence concerns the gene IL15 and metabolic dysfunction-associated steatohepatitis.