Importantly, in patients with sepsis and in septic animal models, the widespread expression of PD-1 and PD-L1 [on immune effector cells (monocytes, T lymphocytes, neutrophils, and NK cells), endothelial cells, and bronchial epithelial cells] suggests the potential ability of PD-1 and PD-L1 to be indicators of immunosuppression and therapeutic agents. Here, PDCD1 is linked to Sepsis.