Mice lacking myeloperoxidase are more susceptible to experimental autoimmune encephalomyelitis

Abstract EAE is a demyelinating disease which serves as an animal model for multiple sclerosis (MS). Myeloperoxidase (MPO) has been implicated in MS through its presence in invading macrophages, and by association of a −463G/A promoter polymorphism with increased risk. Also, MPO at 17q23.1 is within a region identified in genome scans as a MS susceptibility locus. We here examine the incidence of EAE in MPO knockout (KO) mice. MPO is detected in invading macrophages in the CNS of wild-type mice, yet unexpectedly, MPO–KO mice have significantly increased incidence of EAE: Ninety percent of MPO–KO mice developed complete hind limb paralysis as compared to 33% of wildtype (WT) littermates ( P