Epstein-Barr Virus Specific Antibody Response in Multiple Sclerosis Patients during 21 Months of Natalizumab Treatment

Evaluating the Clinical Utility of Epstein-Barr Virus Antibodies as Biomarkers in Multiple Sclerosis: A Systematic Review

BACKGROUND

EBV is a necessary but not sufficient factor in the pathophysiology of multiple sclerosis (MS). EBV antibodies to the nuclear antigen (EBNA1) and viral capsid antigen (VCA) rise rapidly prior to MS disease manifestations, and their absence has clinical utility with a high negative predictive value. It remains unclear whether EBV levels act as prognostic, monitoring, or pharmacodynamic/response biomarkers. Substantial literature on this topic exists but has not been systematically reviewed. We hypothesized that EBV levels against EBNA1 and VCA are potential prognostic and monitoring biomarkers in MS, and that patient population, MS clinical phenotype, and EBV assay method may play important roles in explaining variation among study outcomes.

METHODS

We systematically searched PubMed and EMBASE from inception to April 1, 2022. After removal of duplicates, records were screened by abstract. Remaining full-text articles were reviewed. Clinical and MRI data were extracted from full-text articles for comparison and synthesis.

RESULTS

Searches yielded 696 unique results; 285 were reviewed in full, and 36 met criteria for data extraction. Heterogeneity in sample population, clinical outcome measures, assay methods and statistical analyses precluded a meta-analysis. EBV levels were not consistently associated with clinical disease markers including conversion from CIS to RRMS, neurological disability, or disease phenotype. Studies using repeated-measures design suggest that EBNA1 levels may temporarily reflect inflammatory disease activity as assessed by gadolinium-enhancing Magnetic Resonance Imaging (MRI) lesions. Limited data also suggest a decrease in EBV levels following initiation of certain disease-modifying therapies.

CONCLUSION

Heterogeneous methodology limited generalization and meta-analysis. EBV antibody levels are unlikely to represent prognostic biomarkers in MS. The areas of highest ongoing promise relate to diagnostic exclusion and pharmacodynamic/disease response. Use of EBV antibodies as biomarkers in clinical practice remains additionally limited by lack of methodological precision, reliability, and validation.

From bedside to bench: how existing therapies inform the relationship between Epstein-Barr virus and multiple sclerosis

Therapy for relapsing-remitting multiple sclerosis (MS) has advanced dramatically despite incomplete understanding of the cause of the condition. Current treatment involves inducing broad effects on immune cell populations with consequent off-target side effects, and no treatment can completely prevent disability progression. Further therapeutic advancement will require a better understanding of the pathobiology of MS. Interest in the role of Epstein-Barr virus (EBV) in multiple sclerosis has intensified based on strong epidemiological evidence of an association between EBV seroprevalence and MS. Hypotheses proposed to explain the biological relationship between EBV and MS include molecular mimicry, EBV immortalised autoreactive B cells and infection of glial cells by EBV. Examining the interaction between EBV and immunotherapies that have demonstrated efficacy in MS offers clues to the validity of these hypotheses. The efficacy of B cell depleting therapies could be consistent with a hypothesis that EBV-infected B cells drive MS; however, loss of T cell control of B cells does not exacerbate MS. A number of MS therapies invoke change in EBV-specific T cell populations, but pathogenic EBV-specific T cells with cross-reactivity to CNS antigen have not been identified. Immune reconstitution therapies induce EBV viraemia and expansion of EBV-specific T cell clones, but this does not correlate with relapse. Much remains unknown regarding the role of EBV in MS pathogenesis. We discuss future translational research that could fill important knowledge gaps.

Dimethyl Fumarate Treatment Reduces the Amount but Not the Avidity of the Epstein-Barr Virus Capsid-Antigen-Specific Antibody Response in Multiple Sclerosis: A Pilot Study

(1) Multiple sclerosis (MS) is a chronic inflammatory disease of autoimmune origin. The Epstein−Barr virus (EBV) is associated with the onset of MS, as almost all patients have high levels of EBV-specific antibodies as a result of a previous infection. We evaluated longitudinally the effects of dimethyl fumarate (DMF), a first-line treatment of MS, on the quantity and quality of EBV-specific IgG in MS patients. (2) Serum samples from 17 MS patients receiving DMF were taken before therapy (T0) and after 1 week (T1) and 1 (T2), 3 (T3) and 6 (T4) months of treatment. Anti-EBV nuclear antigen (EBNA)-1 and capsid antigen (CA) IgG levels and anti-CA IgG avidity were measured in all samples. (3) Serum levels of anti-CA IgG were lower at T1 (p = 0.0341), T2 (p = 0.0034), T3 (p < 0.0001) and T4 (p = 0.0023) than T0. These differences were partially confirmed also in anti-EBNA-1 IgG levels (T3 vs. T0, p = 0.0034). All patients had high-avidity anti-CA IgG at T0, and no changes were observed during therapy. (4): DMF can reduce the amount but not the avidity of the anti-EBV humoral immune response in MS patients from the very early stages of treatment.

Serum IgG levels to Epstein-Barr and measles viruses in patients with multiple sclerosis during natalizumab and interferon beta treatment

Background

Patients with multiple sclerosis (MS) demonstrate higher seroprevalence of Epstein-Barr virus (EBV) and increased anti-EBV IgG levels in serum compared with healthy controls. Intrathecal antibody production to measles virus (MeV) is a common finding in patients with MS.

Objective

To measure serum IgG reactivity to EBV glycoprotein 350 (gp350) and MeV nucleocapsid protein (N_CORE) in patients with MS and healthy controls and to determine if reactivity changed in patients during interferon beta (IFNβ) and/or natalizumab (NAT) treatment. A secondary aim was to determine the seroprevalence of EBV in patients and controls.

Methods

Patients with MS (n=728) were included from the Swedish pharmacovigilance study for NAT. Paired serum samples from 714 patients drawn before and during NAT treatment and paired samples from 170 patients during prior IFNβ treatment were analysed. In total, 156 patients were included in both groups. Samples from 144 matched blood donors served as controls. Indirect ELISA was applied using recombinant EBVgp350 and MeV N_CORE as antigens. EBVgp350 IgG seronegative samples were also analysed using EBV nuclear antigen 1 and viral capsid antigen (VCA).

Results

Patients with MS showed higher serum levels of anti-EBVgp350 and anti-MeV N_CORE IgG compared with controls. During NAT treatment, the levels of anti-EBVgp350 and anti-MeV N_CORE IgG declined, compared with the relatively stable levels noted during prior IFNβ treatment. Ten patients failed to demonstrate anti-EBVgp350 IgG but did show detectable anti-VCA IgG, indicating EBV seropositivity. In contrast, 10/144 controls were EBV seronegative.

Conclusions

Treatment with NAT, which is considered a selective immunosuppressive agent with a compartmentalised effect on the central nervous system, appeared to be associated with a moderate decrease in circulating IgG levels to EBVgp350 and MeV N_CORE. All patients with MS were EBV IgG seropositive, supporting the potential role of EBV in the pathogenesis of MS.

Herpesvirus Infections in KIR2DL2-Positive Multiple Sclerosis Patients: Mechanisms Triggering Autoimmunity

In multiple sclerosis (MS), there is a possible relationship with viral infection, evidenced by clinical evidence of an implication of infectious events with disease onset and/or relapse. The aim of this research is to study how human herpesvirus (HHVs) infections might dysregulate the innate immune system and impact autoimmune responses in MS. We analyzed 100 MS relapsing remitting patients, in the remission phase, 100 healthy controls and 100 subjects with other inflammatory neurological diseases (OIND) (neuro-lupus) for their immune response to HHV infection. We evaluated NK cell response, levels of HHVs DNA, IgG and pro- and anti-inflammatory cytokines. The results demonstrated that the presence of KIR2DL2 expression on NK cells increased the susceptibility of MS patients to HHV infections. We showed an increased susceptibility mainly to EBV and HHV-6 infections in MS patients carrying the KIR2DL2 receptor and HLA-C1 ligand. The highest HHV-6 viral load was observed in MS patients, with an increased percentage of subjects positive for IgG against HHV-6 in KIR2DL2-positive MS and OIND subjects compared to controls. MS and OIND patients showed the highest levels of IL-8, IL-12p70, IL-10 and TNF-alpha in comparison with control subjects. Interestingly, MS and OIND patients showed similar levels of IL-8, while MS patients presented higher IL-12p70, TNF-alpha and IL-10 levels in comparison with OIND patients. We can hypothesize that HHVs’ reactivation, by inducing immune activation via also molecular mimicry, may have the ability to induce autoimmunity and cause tissue damage and consequent MS lesion development.

The role of Epstein-Barr virus in multiple sclerosis: from molecular pathophysiology to in vivo imaging

Multiple sclerosis (MS) is a disease of the central nervous system characterized by inflammation, demyelination, and neuronal damage. Environmental and genetic factors are associated with the risk of developing MS, but the exact cause still remains unidentified. Epstein-Barr virus (EBV), vitamin D, and smoking are among the most well-established environmental risk factors in MS. Infectious mononucleosis, which is caused by delayed primary EBV infection, increases the risk of developing MS. EBV may also contribute to MS pathogenesis indirectly by activating silent human endogenous retrovirus-W. The emerging B-cell depleting therapies, particularly anti-CD20 agents such as rituximab, ocrelizumab, as well as the fully human ofatumumab, have shown promising clinical and magnetic resonance imaging benefit. One potential effect of these therapies is the depletion of memory B-cells, the primary reservoir site where EBV latency occurs. In addition, EBV potentially interacts with both genetic and other environmental factors to increase susceptibility and disease severity of MS. This review examines the role of EBV in MS pathophysiology and summarizes the recent clinical and radiological findings, with a focus on B-cells and in vivo imaging. Addressing the potential link between EBV and MS allows the better understanding of MS pathogenesis and helps to identify additional disease biomarkers that may be responsive to B-cell depleting intervention.

Massive intracerebral Epstein-Barr virus reactivation in lethal multiple sclerosis relapse after natalizumab withdrawal

Rebound of disease activity in multiple sclerosis patients after natalizumab withdrawal is a potentially life-threatening event. To verify whether highly destructive inflammation after natalizumab withdrawal is associated with Epstein-Barr virus (EBV) reactivation in central nervous system infiltrating B-lineage cells and cytotoxic immunity, we analyzed post-mortem brain tissue from a patient who died during a fulminating MS relapse following natalizumab withdrawal. Numerous EBV infected B cells/plasma cells and CD8+ T cells infiltrated all white matter lesions; the highest frequency of EBV lytically infected cells and granzyme B+ CD8+ T cells was observed in actively demyelinating lesions. These results may encourage switching to B-cell depleting therapy after natalizumab discontinuation.

Natalizumab Therapy Modulates miR-155, miR-26a and Proinflammatory Cytokine Expression in MS Patients

MicroRNAs fine-tune the regulation of Th1/Th17 lymphocyte subsets in multiple sclerosis. We investigated the expression of miRNAs (previously associated with mycobacterial and viral infections) in MS patients and healthy donors (HD) following 6 months natalizumab therapy. In addition, Th1/Th17 cytokines and the presence of anti-EBNA1/VCA IgG in MS patients with different pattern of miRNA expression have been evaluated. MiR-155, miR-26a, miR-132, miR-146a and Th1/Th17 cytokines expression was detected by RT-real time PCR; moreover anti-EBNA1 and VCA IgG titres were measured by ELISA. We observed an up-regulation of miR-155 (p value = 0.009) and miR-132 (p value = 0.04) in MS patients compared to HD. In MS patients, IL-17a (p = 0.037), IFN γ (p = 0.012) and TNFα (p = 0.015) but not IL-6 were over-expressed compared to HD. Two different miRNAs patterns associated to the expression of different cytokines were observed in the MS cohort. Moreover, a down-regulation of miR-155 and miR-26a was seen in MS patients during and after natalizumab therapy. MS patients that over-expressed miR-155 showed a higher EBNA1 IgG titer than MS patients with high levels of miR-26a. In conclusions the expression of particular miRNAs modulates the pro-inflammatory cytokine expression and the humoral response against EBV and this expression is natalizumab regulated.

Serum Gelatinases Levels in Multiple Sclerosis Patients during 21 Months of Natalizumab Therapy

Background. Natalizumab is a highly effective treatment approved for multiple sclerosis (MS). The opening of the blood-brain barrier mediated by matrix metalloproteinases (MMPs) is considered a crucial step in MS pathogenesis. Our goal was to verify the utility of serum levels of active MMP-2 and MMP-9 as biomarkers in twenty MS patients treated with Natalizumab. Methods. Serum levels of active MMP-2 and MMP-9 and of specific tissue inhibitors TIMP-1 and TIMP-2 were determined before treatment and for 21 months of therapy. Results. Serum levels of active MMP-2 and MMP-9 and of TIMP-1 and TIMP-2 did not differ during the treatment. The ratio between MMP-9 and MMP-2 was increased at the 15th month compared with the 3rd, 6th, and 9th months, greater at the 18th month than at the 3rd and 6th months, and higher at the 21st than at the 3rd and 6th months. Discussion. Our data indicate that an imbalance between active MMP-9 and active MMP-2 can occur in MS patients after 15 months of Natalizumab therapy; however, they do not support the use of serum active MMP-2 and active MMP-9 and TIMP-1 and TIMP-2 levels as biomarkers for monitoring therapeutic response to Natalizumab.