CCL2 and inflammatory bowel disease: Furthermore, among inflamed samples from IBD patients, FNDC4 gene expression correlated with TNF (r=0.654, P<0.0001; Pearson's correlation coefficient; Supplementary Fig. 3d) and CCL2 (MCP1) gene expression (r=0.612, P<0.0001; Pearson's correlation coefficient; Supplementary Fig. 3e), further supporting the notion that FNDC4 is regulated with inflammation.