Conversely, co-stimulation of RRMS T cells with a liver X receptor (LXR)-agonist (a nuclear receptor important for lipid homeostasis), normalized membrane cholesterol levels, and reduced proliferation and IL17 cytokine production, suggesting that defects in LXR-mediated lipid metabolism pathways could contribute to RRMS pathogenesis. This evidence concerns the gene IL17A and relapsing-remitting multiple sclerosis.