CD8A and metabolic dysfunction-associated steatotic liver disease: Furthermore, the frequency of PD1+ T cells is significantly decreased in vitro by treatment with fatty acids that increase in NAFLD/NASH patients [17]; the decrease in PD1 expression due to the increased fatty acid may be related to impaired lipid metabolism, which might be the reason why the frequency of peripheral CD8+ PD1+ T cells was decreased in NASH despite the state of immune activation.