title: Immunopathological significance of ovarian teratoma in patients with anti-N-methyl-d-aspartate receptor encephalitis.
abstract: BACKGROUND
  The clinical importance of ovarian teratoma in anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis has been established, however investigations of ovarian teratoma in patients with anti-NMDAR encephalitis remain limited.
  
  
  OBJECTIVE
  To clarify differences in NMDAR distribution and lymphocyte infiltration in ovarian teratoma between patients with and without anti-NMDAR encephalitis.
  
  
  METHODS
  Participants initially comprised 26 patients with ovarian teratomas. NMDAR distribution and lymphocyte infiltration in ovarian teratomas were examined using immunopathological techniques. Clinical, laboratory, and radiological data were compared between patients showing the features of encephalitis. Anti-NMDAR antibodies in the serum and cerebrospinal fluid were also measured in encephalitis patients.
  
  
  RESULTS
  Neuronal tissues were obtained from ovarian teratomas in 22 patients (after excluding 4 patients who did not satisfy the inclusion criteria), and the presence of NMDA receptor subunits was revealed in all patients. Lymphocyte infiltration was more frequent in the encephalitis group (n = 3) than in the non-encephalitis group. In particular, dense B-lymphocyte infiltration near neural tissues was observed in the encephalitis group.
  
  
  CONCLUSIONS
  Differences in lymphocyte infiltration in ovarian teratomas between anti-NMDAR encephalitis and non-encephalitis patients suggest the immunological importance of the ovarian teratoma as the site of antigen presentation in anti-NMDAR encephalitis.
authors.affiliation: Division of Neurology, Department of Internal Medicine, Saga University Faculty of Medicine, Saga, Japan.
authors.forename: Emi
authors.initials: E
authors.lastname: Tabata
authors.forename: Masanori
authors.initials: M
authors.lastname: Masuda
authors.forename: Makoto
authors.initials: M
authors.lastname: Eriguchi
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Yokoyama
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Keiko
authors.initials: K
authors.lastname: Tanaka
authors.forename: Motohiro
authors.initials: M
authors.lastname: Yukitake
authors.forename: Etsuo
authors.initials: E
authors.lastname: Horikawa
authors.forename: Hideo
authors.initials: H
authors.lastname: Hara
mesh_terms: D000293:Adolescent; D000328:Adult; D060426:Anti-N-Methyl-D-Aspartate Receptor Encephalitis / Q000150:complications / Q000276:immunology / Q000378:metabolism* / Q000473:pathology*; D001323:Autoantibodies / Q000032:analysis; D001402:B-Lymphocytes / Q000276:immunology / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008214:Lymphocytes / Q000276:immunology; D008875:Middle Aged; D009474:Neurons / Q000276:immunology / Q000473:pathology; D010051:Ovarian Neoplasms / Q000150:complications / Q000276:immunology* / Q000473:pathology*; D016194:Receptors, N-Methyl-D-Aspartate / Q000276:immunology; D013724:Teratoma / Q000150:complications / Q000276:immunology* / Q000473:pathology*; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D016194:Receptors, N-Methyl-D-Aspartate