Figure 6. Basolateral conditioned medium of Pkhd1^del4/del4 cholangiocytes contains chemokines able to stimulate macrophage recruitment.

A. Migration of RAW 264.7 macrophages was measured in Boyden chambers containing conditioned medium. In Pkhd1^del4/del4 cholangiocytes, basolateral conditioned medium (bl) induced a stronger migratory effect of RAW 264.7 macrophages than the apical medium, or the basolateral medium from WT cholangiocytes (n=4 for both experiments). This effect was significantly inhibited by specific antagonism of CXCL1, CXCL10 and CXC12, and abolished by combined antagonism of CXCL1+CXCL10+CXCL12 or by inhibition of β-catenin signaling with quercetin (50 µM) or ICG-001 (25 µM) (n=4 for each experiment). B–D. As compared with WT, Pkhd1^del4/del4 cultured cholangiocytes expressed significantly higher amounts of CXCL1 (B), CXCL10 (C) and CXCL12 (D) both at mRNA (n=7 for each chemokine) and protein levels in the basolateral medium (n=3 for CXCL1 and CXCL10, n=12 for CXCL12); all chemokine expression levels were significantly reduced by inhibition of β-catenin signaling with quercetin (50 µM) or ICG-001 (25 µM) (n=7 for each chemokine for RT-PCR experiments, n=4 for each chemokine for ELISA experiments) (cholangiocytes derived from mice of 3 months of age). **p<0.01 vs WT, ^p<0.05 vs Pkhd1, ^^p<0.01 vs Pkhd1, °p<0.05 vs Pkhd1 bl, °°p<0.01 vs Pkhd1 bl.