Quantification and Functional Characterization of Antibodies to Native Aquaporin 4 in Neuromyelitis Optica Sudhakar Reddy Kalluri, MSc; Zsolt Illes, MD; Rajneesh Srivastava, MSc; Bruce Cree, MD; Til Menge, MD; Jeffrey L. Bennett, MD, PhD; Achim Berthele, MD; Bernhard Hemmer, MD Arch Neurol.
Neuromyelitis optica is an inflammatory demyelinating disease of the central nervous system associated with autoantibodies against the glial water channel protein aquaporin-4. It has recently been reported that immunoglobulin from neuromyelitis optica patients injected peripherally does not cause lesions in naive rats, but only when pre-existing central nervous system inflammation is present
Aquaporin 4(AQP4) is a water channel protein strongly expressed in the central nervous system in perimicrovessel astrocyte foot processes, the glia limitans, and ependyma. Expression of AQP4 is highest at the blood-brain barrier and blood-spinal cord barrier, supporting its critical function in material transport across these structures. Recently, presence of the anti-aquaporin-4 antibody in sera has been used as an important diagnostic tool for neuromyelitis optica, suggesting a potential role in central nervous system inflammation.
OBJECTIVE: To asses the presence of cortical demyelination in brains of patients with neuromyelitis optica (NMO). NMO is an autoimmune inflammatory demyelinating disease that specifically targets aquaporin-4-rich regions of the CNS. Since aquaporin-4 is highly expressed in normal cortex, we anticipated that cortical demyelination may occur in NMO
Devic’s neuromyelitis optica is an inflammatory demyelinating disorder normally restricted to the optic nerves and spinal cord. Since the identification of a specific autoantibody directed against aquaporin 4, neuromyelitis optica-immunoglobulin G/aquaporin 4 antibody, neuromyelitis optica has been considered an entity distinct from multiple sclerosis
INTRODUCTION: The description of a highly sensitive and specific biomarker for neuromyelitis optica (NMO-IgG/aquaporin-4 antibody) extended the clinical spectrum of NMO to limited forms such as optic neuritis (ON) and longitudinally extensive myelitis (LEM). OBJECTIVE: To asses the sensitivity and specificity of our assay, and to describe the clinical characteristics of the patients who were tested for NMO-IgG. METHODS: NMO-IgG was analysed by immunohistochemistry and confirmed by assay on HEK cells transfected with aquaporin-4.
Neuromyelitis optica (NMO) is an inflammatory autoimmune demyelinating disease of the central nervous system (CNS) which in autoantibodies produced by patients with NMO (NMO-IgG) recognize a glial water channel protein, Aquaporin-4 (AQP4) expressed as two major isoforms, M1- and M23-AQP4, in which the plasma membrane form orthogonal arrays of particles (OAPs). AQP4-M23 is the OAP-forming isoform, whereas AQP4-M1 alone is unable to form OAPs.
BACKGROUND: Neuromyelitis optica (NMO) is a neurological inflammatory disease associated with autoimmunity to aquaporin 4, predominantly localised in astrocytic foot processes. Recent studies have revealed that loss of aquaporin 4 and glial fibrillar acidic protein (GFAP) is a prominent feature of NMO lesions, suggesting astrocytic impairment. OBJECTIVE: To reveal a useful clinical biomarker of NMO.
Abstract Background: Neuromyelitis optica (NMO, Devic syndrome) is an inflammatory disorder of the central nervous system of putative autoimmune etiology that primarily affects the optic nerves and spinal cord. NMO is frequently associated with immunoglobulin G (IgG) antibodies to aquaporin-4 (AQP4-IgG), which are thought to be involved in the pathogenesis of the disease
OBJECTIVE: To evaluate the efficacy and safety of repeated rituximab treatment based on the assessment of peripheral circulating memory B cells over 24 months in patients with relapsing neuromyelitis optica (NMO). DESIGN: Prospective open-label study.
Neuromyelitis optica (NMO; Devic’s disease) and the NMO spectrum disorders are idiopathic inflammatory demyelinating disorders that affect the central nervous system and have a predilection for optic nerves and spinal cord. The identification of NMO-IgG as a disease-specific marker and aquaporin 4 as the target antigen has renewed interest in NMO.
When Mrs G presented to the emergency room, clinical examination with transverse spinal cord syndrome, magnetic resonance imaging, and her complete clinical remission after plasmapheresis as well as lack of response to treatment pointed to longitudinally extensive transverse myelitis, representing an inaugural or limited form of neuromyelitis optica. The diagnosis was confirmed by detection of anti-aquaporin 4 (AQP4) antibodies.