The effect of thymic stromal lymphopoietin(TSLP)on macrophage-derived foam cell formation and the underlying mechanism were studied.Macrophages isolated from C57BL/6 mice were co-cultured in vitro with different concentrations of TSLP or TSLPR-antibody in the presence of oxidized low density lipoprotein(ox-LDL).The effects of TSLP on macrophage-derived foam cell formation were observed by using oil red O staining and intracellular lipid determination.The expression levels of foam cell scavenger receptors(CD36 and SRA)as well as ABCA1 and TSLPR were detected by using RT-PCR and Western blotting.As compared with the control group,TSLP treatment significantly promoted lipid accumulation in macrophages,significantly increased protein expression of CD36 and TSLPR in a dose-dependent manner,and significantly reduced the expression of ABCA1 protein in a dose-dependent manner.No significant differences were noted between the TSLPR-antibody group and the control group.TSLP may down-regulate the expression of cholesterol efflux receptor ABCA1 and up-regulate scavenger receptor expression via the TSLPR signaling pathway,thereby promoting macrophage-derived foam cell formation.
