RNA-binding protein immunoprecipitation experiment was performed to uncover the effect of hucMSCs treatment on the binding of circANKRD42 with hnRNP L. The results showed that hnRNP L bound to pre-mRNA (ANKRD42) in pulmonary fibrosis and hucMSCs treatment reduced the binding amount of hnRNP L with pre-mRNA (ANKRD42) (Figure 5H). Here, HNRNPL is linked to pulmonary fibrosis.