There was no difference of plasma CCL8 levels between 35 NC and 66 IPF patients (p = 0.167; Additional file 4: Figure S3A), and no correlation between CCL8 concentrations in plasma and those in BAL fluids of 60 IPF patients (p = 0.169; Additional file 4: Figure S3B). Here, CCL8 is linked to idiopathic pulmonary fibrosis.