IL15 and acute respiratory distress syndrome: We also found that, (2) by contrast, APAP overdose also activates liver-resident CD103+ cDC1s via gut-microbial PAMP to secret IL-15, which in turn promotes the bystander activation of hepatic CD8+ TRM cells that induced the apoptosis of Ly6Chi monocytes infiltrated into the liver of APAP mice via cell-to-cell interactions and GrzmB secretion, thereby regulating APAP-ALI in APAP mice.