SPDL1 and Sepsis: The area under ROC curve (AUC) of serum soluble PD-L1 (sPD-L1) combined with Sequential Organ Failure Assessment (SOFA) score is known to be of considerable value in the diagnosis of sepsis, and during the first week of ICU treatment, sPD-L1 was a valuable predictor of severe sepsis and septic shock severity and 28-day mortality (194–196).