Neither measurement of aquaporin-4–immunoglobulin G (AQP4-IgG) binding titer or complement-mediated cell killing has clinical utility as a predictor of relapse, or disease severity, in patients with neuromyelitis optica spectrum disorder (NMOSD).
Why this matters
NMOSD-related neurological disability is episodic and incremental, with little to no progression between attacks. Previous research has shown that AQP4-IgG titer rises at the time of NMOSD attacks, activating complement and inducing cell killing of AQP4-expressing cells. A predictive biomarker of NMOSD activity would therefore be valuable for clinicians as it would allow them to adapt their treatment strategies when patients are at greater risk, thus improving outcomes.