CCL18 and idiopathic pulmonary fibrosis: Research has analyzed and compared several commonly observed blood biomarkers in IPF, including chemokines (IL-8, CCL18), matrix metalloproteinases (MMP-1 and MMP-7), growth factors (IGBPs family), circulating T cells, and fibrocytes, but none of these biomarkers have been proven to be specific for IPF or predict disease progression (such as a decline in lung function, acute exacerbations, or the risk of death) [54].