Neuropediatrics 2013; 44 - FV11_02
DOI: 10.1055/s-0033-1337710

Inward rectifying potassium channel KIR4.1-specific antibodies in children with acquired demyelinating CNS disease

V Kraus 1, SR Kalluri 2, U Seidel 3, M Schülke 4, M Schimmel 5, K Rostásy 6, S Leiz 7, S Hosie 8, V Grummel 2, R Srivastava 2, B Hemmer 2
  • 1Kinderklinik Schwabing, TUM, München, Germany
  • 2Department of Neurologie, Klinikum rechts der Isar, TUM, München, Germany
  • 3SPZ Neuropädiatrie, Charite, Campus Virchow Klinikum, Berlin, Germany
  • 4Neuropädiatrie, Charité, Campus Virchow Klinikum, Berlin, Germany
  • 5Neuropädiatrie, Klinikum Augsburg, Augsburg, Germany
  • 6Departement of Pediatrics I, Division of Pediatric Neurology, Medical University Innsbruck, Austria
  • 7Neuropädiatrie, Klinikum Dritter Orden, München, Germany
  • 8Kinderchirurgie Schwabing, TUM, München, Germany

Aims: We investigated the prevalence of antibodies to the inward rectifying potassium channel KIR4.1 (KIR4.1-IgG) in children with acquired demyelinating diseases (ADD) of the central nervous system (CNS). We also compared antibody responses to KIR4.1 and myelin oligodendrocyte glycoproteins (MOG), another potential autoantigen in childhood ADD.

Methods: We measured KIR4.1-IgG by ELISA in children with ADD (n = 47), other neurological diseases (OND, n = 22), systemic autoimmune diseases (AI, n = 22), and healthy controls (HC, n = 18). Specific binding of KIR4.1-IgG was confirmed by immunohistochemistry in a subgroup of KIR4.1-IgG positive patients. Anti-MOG antibodies were measured by a cell-based assay.

Results: None of the 62 OND, AI, or HC patients (0%) but 27 of 47 ADD patients (57.45%) were KIR4.1-IgG antibody positive. We found no difference between different subgroups of ADD. No correlation between KIR4.1-IgG, age or MOG-IgG was observed.

Serum antibodies to KIR4.1 are found in most children with ADD but not in children with other diseases or HC. These findings suggest that KIR4.1 is also an important target of autoantibodies in childhood ADD.