title: Polysialic acid as an antigen for monoclonal antibody HIgM12 to treat multiple sclerosis and other neurodegenerative disorders.
abstract: CNS regeneration is a desirable goal for diseases of brain and spinal cord. Current therapeutic strategies for the treatment of multiple sclerosis (MS) aim to eliminate detrimental effects of the immune system, so far without reversing disability or affecting long-term prognosis in patients. Approachable molecular targets that stimulate CNS repair are not part of the clinical praxis or have not been identified yet. The purpose of this study was to identify the molecular target of the human monoclonal antibody HIgM12. HIgM12 reverses motor deficits in chronically demyelinated mice, a model of MS. Here, we identified polysialic acid (PSA) attached to the neural cell adhesion molecule (NCAM) as the antigen for HIgM12 by using different NCAM knockout strains and through PSA removal from the NCAM protein core. Antibody binding to CNS tissue and primary cells, antibody-mediated cell adhesion, and neurite outgrowth on HIgM12-coated nitrocellulose was detected only in the presence of PSA as assessed by western blotting, immunoprecipitation, immunocytochemistry, and histochemistry. We conclude that HIgM12 mediates its in vivo and in vitro effects through binding to PSA and has the potential to be an effective therapy for MS and neurodegenerative diseases. The human antibody HIgM12 stimulates neurite outgrowth in vitro and promotes function in chronically demyelinated mice, a model of multiple sclerosis. The cellular antigen for HIgM12 was undetermined. Here, we identified polysialic acid attached to NCAM (neural cell adhesion molecule) as the cellular target for HIgM12. This includes glial fibrillary acidic protein (GFAP)-positive mouse astrocytes (GFAP, red; HIgM12, green; DAPI, blue) among other cell types of the central nervous system. These findings indicate a new strategy for the treatment of neuro-motor disorders including multiple sclerosis.
authors: Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors: Jens O
authors: JO
authors: Watzlawik
authors: Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.|Department of Pediatric and Adolescent Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors: Robert J
authors: RJ
authors: Kahoud
authors: Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors: Shermayne
authors: S
authors: Ng
authors: Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors: Meghan M
authors: MM
authors: Painter
authors: Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors: Louisa M
authors: LM
authors: Papke
authors: Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors: Laurie
authors: L
authors: Zoecklein
authors: Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors: Bharath
authors: B
authors: Wootla
authors: Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors: Arthur E
authors: AE
authors: Warrington
authors: Department of Pediatric and Adolescent Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors: William A
authors: WA
authors: Carey
authors: Department of Neurology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
authors: Moses
authors: M
authors: Rodriguez
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000627:therapeutic use*; D000918:Antibody Specificity; D000937:Antigen-Antibody Reactions; D000941:Antigens / Q000276:immunology*; D019002:CD56 Antigen / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D002448:Cell Adhesion; D002478:Cells, Cultured; D002531:Cerebellum / Q000166:cytology; D020278:Demyelinating Autoimmune Diseases, CNS / Q000188:drug therapy*; D004195:Disease Models, Animal; D004353:Drug Evaluation, Preclinical; D006031:Glycosylation / Q000187:drug effects; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009103:Multiple Sclerosis / Q000188:drug therapy* / Q000276:immunology; D009416:Nerve Regeneration; D009439:Neuraminidase / Q000494:pharmacology; D016501:Neurites / Q000187:drug effects; D019636:Neurodegenerative Diseases / Q000188:drug therapy* / Q000276:immunology; D009457:Neuroglia / Q000166:cytology; D009474:Neurons / Q000187:drug effects / Q000276:immunology / Q000648:ultrastructure; D051381:Rats; D017207:Rats, Sprague-Dawley; D012794:Sialic Acids / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000941:Antigens; D019002:CD56 Antigen; C501063:Ncam1 protein, mouse; D012794:Sialic Acids; C021319:polysialic acid; D009439:Neuraminidase
keywords: antigen; cell adhesion; neural cell adhesion molecule; neurite outgrowth; neurological disease; regeneration