Also the high levels of HERV-W expression in B cells throughout the IM and the post-infection stages (Figure 2B), as well as in MS patients [13] might contribute to the process, since B cells have been proposed to be relevant to the etiology and pathogenesis of MS [53], and MS therapies targeting B cells seem effective against the relapsing-remitting forms [54]. This evidence concerns the gene ERVW-1 and myeloid sarcoma.