Of note, TLR2 ligands, including hyaluronan, HMGB1 and peptidoglycan, a component of Gram-positive bacteria, have been detected in EAE and in MS lesions (Back et al., 2005; Visser et al., 2006; Andersson et al., 2008), suggesting that LIF-induction of TLR2 in OLs might actually lead to inhibition of remyelination. This evidence concerns the gene LIF and myeloid sarcoma.