Effect of glatiramer acetate on cerebral grey matter pathology in patients with relapsing-remitting multiple sclerosis

Decoding Gray Matter Involvement in Multiple Sclerosis via Imaging

Multiple sclerosis (MS) is increasingly understood not only as a white matter disease but also involving both the deep and cortical gray matter (GM). GM pathology in people with MS (pwMS) includes the presence of lesions, leptomeningeal inflammation, atrophy, altered iron concentration, and microstructural changes. Studies using 7T and 3T MR imaging with optimized protocols established that GM damage is a principal driver of disease progression in pwMS. Future work is needed to incorporate the assessment of these GM imaging biomarkers into the clinical workup of pwMS and the assessment of treatment efficacy.

Exploring the effect of glatiramer acetate on cerebral gray matter atrophy in multiple sclerosis

BACKGROUND AND PURPOSE

Cerebral gray matter (GM) atrophy is a proposed measure of neuroprotection in multiple sclerosis (MS). Glatiramer acetate (GA) limits clinical relapses, MRI lesions, and whole brain atrophy in relapsing-remitting MS (RRMS). The effect of GA on GM atrophy remains unclear. We assessed GM atrophy in patients with RRMS starting GA therapy in comparison to a cohort of patients with clinically benign RRMS (BMS).

DESIGN/METHODS

We studied 14 patients at GA start [age (mean ± SD) 44.2 ± 7.0 years, disease duration (DD) 7.2 ± 6.4 years, Expanded Disability Status Scale score (EDSS) (median,IQR) 1.0,2.0] and 6 patients with BMS [age 43.0 ± 6.1 years, DD 18.1 ± 8.4 years, EDSS 0.5,1.0]. Brain MRI was obtained at baseline and one year later (both groups) and two years later in all patients in the GA group except one who was lost to follow-up. Semi-automated algorithms assessed cerebral T2 hyperintense lesion volume (T2LV), white matter fraction (WMF), GM fraction (GMF), and brain parenchymal fraction (BPF). The exact Wilcoxon-Mann-Whitney test compared the groups. The Wilcoxon signed rank test assessed longitudinal changes within groups.

RESULTS

During the first year, MRI changes did not differ significantly between groups (p > 0.15). Within the BMS group, WMF and BPF decreased during the first year (p = 0.03). Within the GA group, there was no significant change in MRI measures during each annual period (p > 0.05). Over two years, the GA group had a significant increase in T2LV and decrease in WMF (p < 0.05), while GMF and BPF remained stable (p > 0.05). MRI changes in brain volumes (GMF or WMF) in the first year in the GA group were not significantly different from those in the BMS group (p > 0.5).

CONCLUSIONS

In this pilot study with a small sample size, patients with RRMS started on GA did not show significant GM or whole brain atrophy over 2 years, resembling MS patients with a clinically benign disease course.

Temporal trends of epilepsy in multiple sclerosis

OBJECTIVES

Epilepsy is associated with advanced multiple sclerosis (MS). We aimed to investigate whether the incidence of epilepsy in MS has been affected by the introduction of disease-modifying treatments (DMT) for MS.

MATERIALS AND METHODS

This retrospective study included 14,557 patients from the Swedish MS register with MS onset between 1991 and 2018. Incident diagnoses of epilepsy or any seizure were identified through cross-linkage with the National Patient Register. Next, yearly prevalence of epilepsy as well as 5- and 10 years incidence of epilepsy or any seizure for consecutive years of MS onset were estimated, the latter with Kaplan-Meier analysis. Cox regression was used to adjust the association between the year of MS onset and incidence of epilepsy for baseline variables.

RESULTS

Prevalence of epilepsy in the MS cohort increased from 0.34% in 1991 to 2.54% in 2018 (yearly odds: 1.26 [1.22, 1.29]). The 5 years incidence rate of epilepsy, ranging from 0.4% (95% CI 0.008-0.79%) to 1.3% (95% CI 0.71-1.89%), and the 10 years incidence rate of epilepsy, ranging from 1.1% (95% CI 0.31-1.88%) to 2.6% (95% CI 1.22-3.97%) showed no significant trends (p = .147 and p = .418, respectively). Similarly, no significant trends were found for the incidences of any seizure. The incidence trends of epilepsy remained not significant after adjusting for sex, MS onset type (relapsing or progressive onset), or age at MS onset.

CONCLUSIONS

Our findings do not support the hypothesis that the introduction of novel DMT for MS has reduced the incidence of epilepsy among MS patients.

CSF Levels of CXCL12 and Osteopontin as Early Markers of Primary Progressive Multiple Sclerosis

Background and Objectives

To evaluate the extent of intrathecal inflammation in patients with primary progressive MS (PPMS) at the time of diagnosis and to define markers and a specific inflammatory profile capable of distinguishing progressive from relapsing-remitting multiple sclerosis (RRMS).

Methods

Levels of 34 pro- and anti-inflammatory cytokines and chemokines in the CSF were evaluated at the diagnosis in 16 patients with PPMS and 80 with RRMS. All patients underwent clinical evaluation, including Expanded Disability Status Scale assessment and a 3T brain MRI to detect white matter and cortical lesion number and volume and global and regional cortical thickness.

Results

Higher levels of CXCL12 (odds ratio [OR] = 3.97, 95% CI [1.34–11.7]) and the monocyte-related osteopontin (OR = 2.24, 95% CI [1.01–4.99]) were detected in patients with PPMS, whereas levels of interleukin-10 (IL10) (OR = 0.28, 95% CI [0.09–0.96]) were significantly increased in those with RRMS. High CXCL12 levels were detected in patients with increased gray matter lesion number and volume (p = 0.001, r = 0.832 and r = 0.821, respectively). Pathway analysis confirmed the chronic inflammatory processes occurring in PPMS.

Conclusions

At the time of diagnosis, a specific CSF protein profile can recognize the presence of early intrathecal inflammatory processes, possibly stratifying PPMS with respect to RRMS. Elevated CSF levels of CXCL12 and osteopontin suggested a key role of brain innate immunity and glia activity in MS. These molecules could represent useful candidate markers of MS progression, with implications for the pathogenesis and treatment of progressive MS.

Classification of Evidence

This study provides Class III evidence that CXCL12 and monocyte-related osteopontin may be correlated with PPMS, and IL-10 may be related to RRMS. It is may be correlated due to Bonferroni correction negating the statistical correlations found in the study.

Subcutaneous anti-CD20 antibody treatment delays gray matter atrophy in human myelin oligodendrocyte glycoprotein-induced EAE mice

BACKGROUND

The human myelin oligodendrocyte glycoprotein-induced experimental autoimmune encephalomyelitis (huMOG-EAE) model, generates B-cell driven demyelination in mice, making it a suitable multiple sclerosis model to study B cell depletion.

OBJECTIVES

We investigated the effect of subcutaneous anti-CD20 antibody treatment on huMOG-EAE gray matter (GM) pathology.

METHODS

C57Bl/6, 8-week old mice were immunized with 200 huMOG_1-125 and treated with 50 μg/mouse of anti-CD20 antibody (n = 16) or isotype control (n = 16). Serial brain volumetric 9.4 T MRI scans was performed at baseline, 1 and 5 wkPI. Disease severity was measured by clinical disability score (CDS) and performance on rotarod test.

RESULTS

Anti-CD20 antibody significantly reduced brain volume loss compared with the isotype control across all timepoints longitudinally in the basal ganglia (p = 0.01), isocortex (p = 0.025) and thalamus (p = 0.023). The CDS was reduced significantly with anti-CD20 antibody vs. the isotype control at 3 (p = 0.003) and 4 (p = 0.03) wkPI, while a trend was observed at 5 (p = 0.057) and 6 (p = 0.086) wkPI. Performance on rotarod was also improved significantly at 3 (p = 0.007) and 5 (p = 0.01) wkPI compared with the isotype control. At cellular level, anti-CD20 therapy suppressed the percentage of proliferative nuclear antigen positive microglia in huMOG-EAE isocortex (p = 0.016). Flow cytometry confirmed that anti-CD20 antibody strongly depleted the CD19-expressing B cell fraction in peripheral blood mononuclear cells, reducing it from 39.7% measured in isotype control to 1.59% in anti-CD20 treated mice (p < 0.001).

CONCLUSIONS

Anti-CD20 antibody treatment delayed brain tissue neurodegeneration in GM, and showed clinical benefit on measures of disease severity in huMOG-EAE mice.

Approved and Emerging Disease Modifying Therapies on Neurodegeneration in Multiple Sclerosis

Multiple sclerosis (MS) is an autoimmune, chronic, progressive disease leading to a combination of inflammation, demyelination, and neurodegeneration throughout the central nervous system (CNS). The outcome of these processes can be visualized in magnetic resonance imaging (MRI) scans as brain atrophy, or brain volume loss (BVL), as well as lesions, “black holes” and spinal cord atrophy. MRI outcomes such as BVL have been used as biomarkers of neurodegeneration and other measures of MS disease progression in clinical research settings. Several FDA-approved medications seek to alleviate disease progression by reducing the impact of such factors as demyelination and neurodegeneration, but there are still many shortcomings that current clinical research aims to mitigate. This review attempts to provide an overview of the FDA-approved medications available for treating multiple sclerosis and their effect on neurodegeneration, measured by BVL.

Advances in brain imaging in multiple sclerosis

Brain imaging is increasingly used to support clinicians in diagnosing multiple sclerosis (MS) and monitoring its progression. However, the role of magnetic resonance imaging (MRI) in MS goes far beyond its clinical application. Indeed, advanced imaging techniques have helped to detect different components of MS pathogenesis in vivo, which is now considered a heterogeneous process characterized by widespread damage of the central nervous system, rather than multifocal demyelination of white matter. Recently, MRI biomarkers more sensitive to disease activity than clinical disability outcome measures, have been used to monitor response to anti-inflammatory agents in patients with relapsing-remitting MS. Similarly, MRI markers of neurodegeneration exhibit the potential as primary and secondary outcomes in clinical trials for progressive phenotypes. This review will summarize recent advances in brain neuroimaging in MS from the research setting to clinical applications.