FIGURE 1.

Blood leukocytes of patients with community-acquired pneumonia show an altered cytokine production profile upon ex vivo stimulation. Whole blood leukocytes were obtained from CAP patients at admission (n = 79) and 1 month following admission (n = 55), and from non-infected age and sex-matched controls (n = 42), and stimulated for 24 h with lipopolysaccharide (LPS; 100 ng/mL) or heat-killed Klebsiella pneumoniae (equivalent of 12.5 × 10⁶ CFU/mL). Cytokines were measured in supernatants. Individual data points are displayed with the horizontal line depicting the median. Dotted lines indicate the median concentrations in medium control samples (i.e., blood leukocytes incubated without stimulus), which were all significantly altered compared to LPS and K. pneumoniae stimulation. Asterisks indicate differences between groups as indicated (*P < 0.05, **P < 0.01, ***P < 0.001). IL, interleukin; TNF, tumor necrosis factor; RA, receptor antagonist.