Compared to those with nonpulmonary sepsis, patients with pulmonary sepsis held lower Th1 population on D0 (P = 0.01), D3(P < 0.01), and D7 (P = 0.05) and higher T helper 2 cell population on D7 (P = 0.04), leading to the significant difference of Th2/Th1 observed on D3 (P = 0.02) and D7 (P = 0.04) (Figure 3), while Th1- or Th2-related cytokine levels of IFN-γ, IL-2, IL-4, and IL-10 as well as other inflammatory indicators, including IL-6, ALC, WBC, hs-CRP, and PCT, were comparable in the two groups (Figure 3 and Supplementary Fig S1). Here, IL2 is linked to Sepsis.