Consistent with the results of the 10x Genomics single-cell sequencing technology in human cholangiocarcinoma, ELISA and qPCR showed that TGFβ1 was dramatically upregulated in intracellular and supernatant of M2 macrophages compared with MΦ/M1 macrophages (Supplementary Fig. 4A). Here, TGFB1 is linked to cholangiocarcinoma.