AKT1 and Sepsis: Studies on sepsis mouse models have shown that up-regulation of PD-L1 can inhibit the activity of caspase-3 and up-regulate the expression of Mcl-1 through the PD-1/PI3K/Akt signaling pathway, thereby delaying neutrophil apoptosis, leading to their abnormal accumulation in the lungs and exacerbating lung injury (42).