CD6 and inflammatory bowel disease: We proposed that Sterol ester [Sterol ester (27:1/20:4), Sterol ester (27:1/22:6)], Phosphatidylcholine [Phosphatidylcholine (20:4_0:0), Phosphatidylcholine (16:0_20:4)], and Sphingomyelin [Sphingomyelin (d38:1), Sphingomyelin (d42:2)] exerted a protective effect against IBD, UC, and CD by reducing CD6 and CCL4 levels.