PDCD1 and metabolic dysfunction-associated steatohepatitis: The mouse model in questionreveals that genetic ablation of CD8 T cells engenders the emergenceand advancement of liver injury, NASH, and HCC, leading to the conclusionthat CD8 T cells play a direct role in the progression of disease.156 NASH programming incites CD8 T cells to assumean exhausted, activated phenotype and exhibit elevated expressionlevels of programmed cell death protein-1 (PD-1) upon exposure tometabolic stimuli such as IL-15.