LGALS9 and multiple sclerosis: While galectin-9 protein or the gene encoding galectin-9, Lgals9, is not normally expressed at high levels within the CNS [35,36], it is increased following experimental pneumococcal meningitis [37] as well as infection with herpes simplex virus [38] or Japanese encephalitis virus [39] and is reportedly increased in the brains of multiple sclerosis patients [34,40], indicating that it becomes up-regulated during inflammatory conditions.