Evaluation of hypothalamic-specific autoimmunity in patients with narcolepsy.

Neurology Service, Hospital Clinic de Barcelona and Institut d'Investigació Biomédica August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
Sleep (Impact Factor: 5.06). 02/2007; 30(1):27-8.
Source: PubMed

ABSTRACT An autoimmune-mediated mechanism is considered the most probable etiology for narcolepsy. However, this hypothesis remains unproven. Since narcolepsy is characterized by dysfunction of the hypothalamic hypocretinergic (orexinergic) system, we evaluated the presence of hypothalamic-specific antibodies in sera and CSF of 25 hypocretin-deficient and 6 non-deficient narcoleptic patients by immunohistochemistry and analyzing a screening of a rat cDNA expression hypothalamic library. There was no hypothalamic-specific reactivity in serum or CSF by inmmunohistochemistry. The screening of the hypothalmic library detected some reactive clones but not a common reactivity. Our study did not find any evidence of hypothalamic-specific autoimmunity in narcolepsy.

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