In addition, the single-sample gene set enrichment analysis (ssGSEA) algorithm was utilized to estimate the immune infiltration characteristic of sepsis in clusters A and B. The result displayed a remarkable difference in 23 kinds of immune cells between the two sepsis subgroups, such as activated B cells, CD4+ T cells, immature dendritic cells, and plasmacytoid dendritic cells (Figure 7D). Here, CD4 is linked to Sepsis.