CD4 and Sepsis: Boomer et al11 reported that spleens that were obtained rapidly after the death of patients with sepsis showed evidence that is highly consistent with the occurrence of T‐cell exhaustion; profound suppression of the production of IFN‐γ by stimulated T cells; increased expression of programmed cell death‐1 (PD‐1) on CD4+ T cells and programmed cell death 1 ligand 1 (PD‐L1) on macrophages.