CCL17 and idiopathic pulmonary fibrosis: Moreover, CCL17 has been confirmed as a circulating biomarker of fibrosis-associated diseases, such as idiopathic pulmonary fibrosis (Sivakumar et al., 2021), cystic fibrosis (Adib-Conquy et al., 2008), peritoneal (Chen et al., 2020), and renal fibrosis (Hsieh et al., 2021; Pai et al., 2020).