CCL21 and idiopathic interstitial pneumonia: The ligands of CCR7, CCL19 (mean±SD, 0.002±0.004 versus 0.0005±0.0007) and CCL21 (mean±SD, 0.0005±0.0008 versus 0.0002±0.0002) were overexpressed in the infected samples from IPF patients with a ratio of 4 and 2.5, respectively, over the expression of the mock infected samples (Figure 6).