Narcolepsy: Role of H1N1 vaccination and infection

Abstract

Narcolepsy type 1 is an orphan hypersomnia disorder characterized by excessive daytime sleepiness and cataplexy, frequent hypnagogic hallucinations, sleep paralysis and nocturnal sleep disturbances. Narcolepsy type 1 is an immune system-associated disease linked with the destruction of hypocretin neurons. More than 92 % of narcoleptic patients are positive for HLA-DQB1∗06:02, against 20-25% in general population. Other genes involved in CD4+ T cells and immune system activation as T-cell receptor a are also associated with narcolepsy. The development of the disease is linked with environmental factors such as streptococcal and influenza (AIH1N1) infections, and the use of a 2009 H1N1 AS03-adjuvanted vaccine named Pandemrix®. The hypothesis of autoimmune destruction of hypocretin-producing neurons may be driven by molecular mimicry between an H1N1 virus-derived antigen and a neuronal autoantigen within hypocretin neurons.