Differential Regulation of IgG-NMO Autoantibodies on S100Beta Protein and Disability in Relapsing Neuromyelitis Optica

Abstract

Neuromyelitis optica (NMO), an uncommon central nervous system (CNS) demyelinating disease, produces transverse myelitis and severe optic neuritis. IgG-NMO autoantibody, a specific immunoglobulin binding aquaporin-4 water channel protein, confirms that NMO is a different entity to multiple sclerosis. Parallel to cytokine down-regulations found in serum of relapsing-NMO (rNMO) patients, it has been reported that IgG-NMO may also confer a worse course of the disease in r-NMO Caribbean patients. In this study, we were interested in exploring the influence of IgG-NMO autoantibody on S100β levels and clinical parameters from serum of r-NMO patients. Serum samples from 24 rNMO patients and 10 controls were evaluated. The reduction of S100β observed in r-NMO patients was not significant compared to controls; and no differences were present regarding IgG-NMO immunoreactivity. At the same time, a significant correlation was also observed between IgG-NMO autoantibody serum detection and EDSS (Expanded Disability Status Scale) in rNMO. These results corroborate a differential regulation of IgG-NMO autoantibodies on the S100β glial marker and on the disability present in rNMO patients.

Notable Increased Cerebrospinal Fluid Levels of Soluble Interleukin-6 Receptors in Neuromyelitis Optica

“…Unlike MS, NMO may be a disease mediated by humoral immunity. The serum autoantibody of aquaporin-4 (AQP4-Ab) is suggested to be a specific biomarker of NMO, which can help to distinguish it from MS [4,5,6]. …”

Serum GFAP levels in optic neuropathies

“…For S100B, there are a number of studies demonstrating that serum and CSF levels were not correlated in a number of diseases including MS [26][27][28][29]. Likewise, a recent study on serum GFAP and S100B levels in NMO did not find a correlation of concentrations between body fluid compartments [30]. In contrast to these results one study did find in AQP4 autoantibody positive patients that serum and CSF levels of both glial biomarkers were highly correlated [31].…”

Identification of potential biomarkers for neuromyelitis optica by quantitative proteomics

“…13 Some of the proteins associated with astrocyte damage can also be used as potential markers for NMO such as S100b and GFAP. 14,15 Several studies have been conducted on proteomic testing for patients with NMO. The proteome of CSF immunoglobulin in NMO patients indicated that a significant percentage of intrathecal Ig proteins were generated by intrathecal B-cell populations that consist of clones derived from both neo-and peripheral origins.…”

“…A recent study had shown high levels of heparan sulfate and hyaluronic acid in serum and the CSF may be biomarkers of NMO severity 13 . Some of the proteins associated with astrocyte damage can also be used as potential markers for NMO such as S100β and GFAP 14,15 …”