Anti-Argonaute Antibodies for the Diagnosis of Sensory Neuronopathies

Sensory neuronopathies (SNN) are rare and debilitating diseases that fall under several etiologies. Among them, dysimmune forms are the most frequent but very difficult to identify when they do not occur in the context of associated systemic dysimmune disease (Sjögren Syndrome (SS) syndrome) because only a biopsy of the epiphytically unthinkable posterior spinal node would support the diagnosis. It is therefore necessary to have diagnostic biological markers of these forms to consider rapid treatment before irreversible neuronal degeneration.Using a protein-array technique, it has been showed that anti-FGFR3 antibodies was one of these markers and that it was associated with a clinical picture that differentiated from Sensory neuronopathies (SNN) without this antibody. Protein-array also allowed to identify another potentially interesting antibody for the diagnosis of Sensitive neuronopathies (NNS). This antibody recognizes the AGO1 protein. Anti-AGO1 antibodies have been described in association with system autoimmune diseases and in particular lupus but not in neurological diseases and more particularly in Sensory neuronopathies (SNN). The study want to validate the diagnostic interest of these antibodies by testing the collection of serums performed for studies on the anti-FGFR3 antibody and including patients with Sensory neuronopathies (SNN) and as controls of patients with another form of neuropathy and subjects with systemic autoimmune disease without peripheral neuropathy.