Lin CC, Bradstreet TR, Schwarzkopf EA, Sim J, Carrero JA, Chou C, Cook LE, Egawa T, Taneja R, Murphy TL, Russell JH, Edelson BT. Bhlhe40 controls cytokine production by T cells and is essential for pathogenicity in autoimmune neuroinflammation. Nat Commun. 2014 Apr 3;5:3551. doi: 10.1038/ncomms4551.
TH1 and TH17 cells mediate neuroinflammation in experimental autoimmune encephalomyelitis (EAE), a mouse model of multiple sclerosis. Pathogenic TH cells in EAE must produce the pro-inflammatory cytokine granulocyte-macrophage colony stimulating factor (GM-CSF). TH cell pathogenicity in EAE is also regulated by cell-intrinsic production of the immunosuppressive cytokine interleukin 10 (IL-10). Here we demonstrate that mice deficient for the basic helix-loop-helix (bHLH) transcription factor Bhlhe40 (Bhlhe40(-/-)) are resistant to the induction of EAE. Bhlhe40 is required in vivo in a T cell-intrinsic manner, where it positively regulates the production of GM-CSF and negatively regulates the production of IL-10. In vitro, GM-CSF secretion is selectively abrogated in polarized Bhlhe40(-/-) TH1 and TH17 cells, and these cells show increased production of IL-10. Blockade of IL-10 receptor in Bhlhe40(-/-) mice renders them susceptible to EAE. These findings identify Bhlhe40 as a critical regulator of autoreactive T-cell pathogenicity.
Granulocyte-macrophage colony-stimulating factor (GM-CSF is a protein secreted by macrophages, T cells, mast cells, NK cells, endothelial cells and fibroblasts and interleukin-ten is a cytokine that can regulate T cell function, incluing that activated via the basic helix loop transcription factor. However, Interelukin ten is also a B cell growth factor. So would it succeed or fail in MS?