In an experimental autoimmune encephalomyelitis mouse model, we observed that β-elemene selectively downregulated CD4+ T lymphocytes without affecting the activation of peripheral lymphoid tissue, significantly weakened the signs in the nervous system and the development of experimental autoimmune encephalomyelitis (EAE), inhibited the Th1 cell-mediated immune response, and upregulated the Treg cell response in vitro [128]. Here, CD4 is linked to experimental autoimmune encephalomyelitis.