Rapamycin and fingolimod modulate Treg/Th17 cells in experimental autoimmune encephalomyelitis by regulating the Akt-mTOR and MAPK/ERK pathways.

Rapamycin prevents experimental autoimmune encephalomyelitis (EAE) and activates the MAPK/ERK pathway in EAE. Thus, we hypothesized combining rapamycin and fingolimod treatments would have synergistic effects in EAE. We show that combination therapy ameliorated EAE and regulated spinal cord IL-17 and TGF-β levels in EAE mice. Combination therapy also modulated IL-17 and TGF-β concentration, RoRγt and Foxp3 mRNA levels, and Th17 cell and Treg frequencies in the spleen. Moreover, rapamycin decreased ps6k and increased pAkt and pERK, while combination therapy downregulated pAkt, ps6 k and pERK in EAE mice. Our findings provide insight into using this drug combination to treat EAE.