Differentiation of remitting neuromyelitis optica spectrum disorders from multiple sclerosis by integrating parameters from serum proteins and lymphocyte subsets

NMOSD IgG Impact Retinal Cells in Murine Retinal Explants

Neuromyelitis optica spectrum disorders (NMOSD) are chronic inflammatory diseases of the central nervous system, characterized by autoantibodies against aquaporin-4. The symptoms primarily involve severe optic neuritis and longitudinally extensive transverse myelitis. Although the disease progression is typically relapse-dependent, recent studies revealed retinal neuroaxonal degeneration unrelated to relapse activity, potentially due to anti-aquaporin-4-positive antibodies interacting with retinal glial cells such as Müller cells. In this exploratory study, we analysed the response of mouse retinal explants to NMOSD immunoglobulins (IgG). Mouse retinal explants were treated with purified IgG from patient or control sera for one and three days. We characterized tissue response patterns through morphological changes, chemokine secretion, and complement expression. Mouse retinal explants exhibited a basic proinflammatory response ex vivo, modified by IgG addition. NMOSD IgG, unlike control IgG, increased gliosis and decreased chemokine release (CCL2, CCL3, CCL4, and CXCL-10). Complement component expression by retinal cells remained unaltered by either IgG fraction. We conclude that human NMOSD IgG can possibly bind in the mouse retina, altering the local cellular environment. This intraretinal stress may contribute to retinal degeneration independent of relapse activity in NMOSD, suggesting a primary retinopathy.

Platelet-to-lymphocyte ratio differs between MS and NMOSD at disease onset and predict disability

BACKGROUND

We aimed to assess platelet-to-lymphocyte (PLR) and neutrophil-to-lymphocyte ratios (NLR) for differentiating multiple sclerosis (MS) from aquaporin-4-antibody-positive neuromyelitis optica spectrum disorders (NMOSD) at disease onset.

METHODS

We retrospectively enrolled and reviewed the medical records of patients with MS (N = 50) and NMOSD (N = 33) followed in specialized MS/NMOSD centers from Argentina. Demographical and clinical (manifestation and disability) data and neuroradiological features (new/enlarging or contrast-enhancing lesions) were assessed at baseline, 1 and 2 years. Serum samples were obtained during the first relapse without a previous acute or chronic treatment, at 1 and 2 years. Mixed-effects model was used to identify independent associations between the log-transformed NLR or PLR and MS/NMOSD outcomes.

RESULTS

PLR is increased in NMOSD when compared to MS (229.4 ± 86.74 vs. 186.6 ± 70.17, P = 0.01), but no significant differences were found for NLR (3.51 ± 1.29 vs. 3.30 ± 1.17, P = 0.43). PLR was the only independent predictor of poor physical disability score (EDSS ≥ 4) in NMOSD patients at 2 years (β=0.28, p = 0.02) after applying multivariate mixed-effects regression analysis. Additionally, multivariate logistic regression analysis showed that the PLR was the only independent predictor of EDSS ≥ 4 at 2 years (OR 28.8, p = 0.041) in the NMOSD group. The area under the receiver-operating characteristic curve was 0.841.

CONCLUSION

PLR could be potentially useful as additional diagnostic tool in differentiating these two neuroinflammatory conditions at presentation. PLR can predict severity of neurological disability at 2 years in NMOSD patients.

Th17-Related Cytokines as Potential Discriminatory Markers between Neuromyelitis Optica (Devic's Disease) and Multiple Sclerosis-A Review

Multiple sclerosis (MS) and Devic’s disease (NMO; neuromyelitis optica) are autoimmune, inflammatory diseases of the central nervous system (CNS), the etiology of which remains unclear. It is a serious limitation in the treatment of these diseases. The resemblance of the clinical pictures of these two conditions generates a partial possibility of introducing similar treatment, but on the other hand, a high risk of misdiagnosis. Therefore, a better understanding and comparative characterization of the immunopathogenic mechanisms of each of these diseases are essential to improve their discriminatory diagnosis and more effective treatment. In this review, special attention is given to Th17 cells and Th17-related cytokines in the context of their potential usefulness as discriminatory markers for MS and NMO. The discussed results emphasize the role of Th17 immune response in both MS and NMO pathogenesis, which, however, cannot be considered without taking into account the broader perspective of immune response mechanisms.

Association of Circulating Follicular Helper T Cells and Serum CXCL13 With Neuromyelitis Optica Spectrum Disorders

Background

Neuromyelitis optica spectrum disorders (NMOSDs) are severe inflammatory diseases mediated mainly by humoral and cellular immunity. Circulating follicular helper T (Tfh) cells are thought to be involved in the pathogenesis of NMOSD, and serum C-X-C motif ligand 13 (CXCL13) levels reflect the effects of Tfh cells on B-cell-mediated humoral immunity. Immune cell and cytokine changes during the dynamic relapsing and remitting processes in NMOSD require further exploration.

Patients and methods

Blood samples were collected from 36 patients in acute and recovery phases of NMOSD, 20 patients with other noninflammatory neurological diseases (ONND) and 20 age- and sex-matched healthy volunteers. CD4+CXCR5+PD-1+ Tfh cells were detected by flow cytometry, and serum CXCL13 levels were assessed by enzyme-linked immunosorbent assay (ELISA).

Results

The percentage of CD4+CXCR5+PD-1+ Tfh cells was significantly higher during the acute phase than during the recovery phase, and serum CXCL13 levels were significantly higher in patients in the acute and recovery phases of NMOSD than in the ONND and control groups. The Tfh cell percentage was positively correlated with CXCL13 levels, and both were positively correlated with Expanded Disability Status Scale (EDSS) scores and cerebrospinal fluid protein levels in patients with acute NMOSD.

Conclusion

Circulating Tfh cells level has the potential to be a biomarker of disease severity.

Analysis of site-specific glycan profiles of serum proteins in patients with multiple sclerosis or neuromyelitis optica spectrum disorder - a pilot study

Glycosylation is important for biological functions of proteins and greatly affected by diseases. Exploring the glycosylation profile of the protein-specific glycosylation and/or the site-specific glycosylation may help understand disease etiology, differentiate diseases, and ultimately develop therapeutics. Patients with multiple sclerosis (MS) and patients with neuromyelitis optica spectrum disorder (NMOSD) are sometimes difficult to differentiate due to the similarity in their clinical symptoms. The disease-related glycosylation profiles of MS and NMOSD have not yet been well studied. Here, we analyzed site-specific glycan profiles of serum proteins of these patients by using a recently developed mass spectrometry technique. A total of 286 glycopeptides from 49 serum glycoproteins were quantified and compared between healthy controls (n = 6), remitting MS (n = 45) and remitting NMOSD (n = 23) patients. Significant differences in the levels of site-specific N-glycans on inflammation-associated components [IgM, IgG1, IgG2, complement components 8b (CO8B), attractin], central nerve system-damage-related serum proteins [apolipoprotein D (APOD), alpha-1-antitrypsin, plasma kallikrein and ADAMTS-like protein 3] were observed among three study groups. We furthered demonstrated that site-specific N-glycans on APOD on site 98, CO8B on sites 243 and 553 are potential markers to differentiate MS from NMOSD with an area under receiver operating curve value greater than 0.75. All these observations indicate that remitting MS or NMOSD patients possess a unique disease-associated glyco-signature in their serum proteins. We conclude that monitoring one's serum protein glycan profile using this high-throughput analysis may provide an additional diagnostic criterion for differentiating diseases, monitoring disease status and estimating response-to-treatment effect.

Next-Generation Neuroimmunology: New Technologies to Understand Central Nervous System Autoimmunity

Understanding neuroimmunological disorders is essential for developing new diagnostic and therapeutic strategies. Rodent models have provided valuable insights, but are sometimes equated with their human counterparts. Here, we summarize how novel technologies may enable an improved human-focused view of immune mechanisms. Recent studies have applied these new technologies to the brain parenchyma, its surrounding cerebrospinal fluid, and peripheral immune compartments. Therapeutic interventions have also facilitated translational understanding in a reverse way. However, with improved technology, access to patient samples remains a rate-limiting step in translational research. We anticipate that next-generation neuroimmunology is likely to integrate, in the immediate future, diverse technical tools for optimal diagnosis, prognosis, and treatment of neuroimmunological disorders.