IL2 and susceptibility to pneumonia measurement: Elevated concentrations of both pro- and anti-inflammatory plasma cytokines were observed in the pneumonia group (Figure 4 and Table S5), including G-CSF, HGF, IL-1b, IL-1RA, IL-2, IL-2Ra, IL-6, IL-10, IL-18, IP-10, monocyte chemoattractant protein-3 (MCP-3), and TNF-α.