Compared with the control group, the fractions of naive B cells, CD8 T cells, naive CD4 T cells, memory-activated CD4 T cells, resting NK cells, M2 macrophages, and resting dendritic cells had a lower abundance in patients with sepsis, while the fractions of T cells, plasma cells, resting CD4 memory, gamma delta T cells, monocytes, M0 macrophages, eosinophils, and neutrophils were significantly higher than those in the control group, indicating that acute inflammation and cell immunity play a crucial role in the pathophysiology of sepsis. The gene discussed is CD8A; the disease is Sepsis.