Neuromyelitis optica and anti-aquaporin-4 antibodies measured by an enzyme-linked immunosorbent assay

Abstract

NMO-IgG, a disease-specific autoantibody for neuromyelitis optica, recognizes aquaporin-4 (AQP4) and has been examined by indirect immunofluorescence assay. We developed an enzyme-linked immunosorbent assay (ELISA) to detect anti-AQP4 antibodies by establishing methods for expression in a baculovirus system and purification of recombinant AQP4 as antigen. Elevated anti-AQP4 antibody titers in serum were found in 15 (71%) of 21 patients with neuromyelitis optica, 4.3% of 46 patients with multiple sclerosis, none of 51 normal controls, and 2.6% of 115 patients with other neurological diseases. The ELISA system can be substituted for the conventional NMO-IgG assay.

Seroconversion of anti-aquaporin-4 antibody in NMO spectrum disorder: a case report

“…Brain MRI detected no abnormality consistent with Barkhof's criteria [5]. Anti-AQP4 antibodies, measured by enzyme-linked immunosorbent assays [6] in a serum sample obtained on May 18, 2010 were positive. Our diagnosis was NMOsd.…”

Anti-Aquaporin-4 Antibody-Seronegative NMO Spectrum Disorder with Baló's Concentric Lesions

“…Common biochemical laboratory tests were normal. The level of anti-APQ4 antibodies was tested as previously reported (14), and a serum sample obtained nine days after the neurologic onset was negative. Antinuclear, antineutrophil cytoplasmic, anti-SSA/RO, anti-SSB/LA and antiphospholipid antibodies were also negative.…”

Markedly increased CSF interleukin-6 levels in neuromyelitis optica, but not in multiple sclerosis

“…We examined CSF samples obtained at the time of relapse from NMO patients fulfilling Wingerchuk's criteria [15] using seropositivity of anti-AQP4 antibody [4] instead of NMO-IgG (n = 17; all women; mean age, 49.6 years) and relapsing-remitting MS fulfilling McDonald's criteria [10] (n = 21; 17 women and 4 men; mean age, 30.9 years). Anti-AQP4 antibody was positive in 17 (76%) NMO patients and 1 (5%) MS patient.…”