IgLON5 antibodies


In case of suspected autoimmune encephalitis


Indirect immunofluorescence (IIF)


The result is expressed as negative or positive with titer.


The IgLON5 protein is a neuronal cell surface adhesion molecule with unknown function. Antibodies against IgLON5 has been found in a few cases in patients with encephalitis and neurodegeneration with abnormal sleep movements and behavior and obstructive sleep apnea.  Other present neurological symptoms are gait instability, dysarthria, dysphagia, ataxia or chorea.

The antigen has been defined as an extracellular antigen.

Generally, treatment with immunotherapy is more effective against auto-antibodies directed to extracellular antigens than with auto-antibodies against intracellular antigens.

Read more about sampling


Sabater L et. al. A novel non-rapid-eye movement and rapid-eye-movement parasomnia with sleep breathing disorder associated with antibodies to IgLON5: a case series, characterisation of the antigen, and post-mortem study. Lancet Neurol. 2014 Jun;13(6):575-86. PMID: 24703753

Leypoldt F, Armangue T, Dalmau J. Autoimmune encephalopathies. Ann N Y Acad Sci. 2014 Oct 14. PMID: 25315420

Clinical studies