Brain endothelial PPARγ controls inflammation-induced CD4+ T cell adhesion and transmigration in vitro

We provide molecular evidence that the transcription factor peroxisome proliferator-activated receptor gamma (PPARγ) is a negative regulator of brain EC inflammation. The PPARγ agonist pioglitazone reduces transendothelial migration of encephalitogenic T cells across TNFα-stimulated brain EC. This effect is clearly PPARγ mediated, as lentiviral PPARγ overexpression in brain EC results in selective abrogation of inflammation-induced ICAM-1 and VCAM-1 upregulation and subsequent adhesion and transmigration of T cells. We therefore propose that PPARγ in brain EC may be exploited to target detrimental EC-T cell interactions under inflammatory conditions.