Humoral and Cellular Responses to SARS-CoV-2 in Convalescent COVID-19 Patients With Multiple Sclerosis

Risk of breakthrough COVID-19 after vaccination among people with multiple sclerosis on disease-modifying therapies

BACKGROUND

Disease-modifying therapies (DMTs) for people with multiple sclerosis (pwMS) may decrease vaccine effectiveness. We aimed to explore the association between various DMTs and the risk for breakthrough COVID-19.

METHODS

Population-based data from Clalit Health Services, Israel's largest healthcare organization, were used. PwMS treated with DMTs without prior COVID-19 were followed from the commencement of the mass vaccination campaign in December 2020. The end of follow-up was at the time of COVID-19 infection, the receipt of a third vaccine dose or until the end of August 2021. Time-dependent multivariate Cox proportional hazard models were used to estimate hazard ratios for COVID-19 according to vaccination, DMT, age, gender, disability and comorbidities.

RESULTS

2511 PwMS treated with DMTs were included (Age: 46.2 ± 14.6, 70% Female, EDSS: 3.0 ± 2.1). Of whom, 2123 (84.5%) received 2 vaccine doses. On multivariate models that included all pwMS, vaccination was protective (HR = 0.41, P < 0.001). On multivariate models that included only fully vaccinated pwMS cladribine, ocrelizumab, S1P receptor modulators and natalizumab were associated with breakthrough COVID-19 (HR = 6.1, 4.7, 3.7 and 3.3; P = 0.004, 0.008, 0.02 and 0.05, respectively). On multivariate models that included unvaccinated and fully vaccinated pwMS on each DMT separately, a protective trend was noted for vaccination on all DMTs (0.09 < HR < 0.65), except for cladribine (HR = 1.1). This protective trend was not statistically significant on ocrelizumab, S1P receptor modulators and natalizumab. COVID-19 among pwMS was generally mild. Only 2 vaccinated pwMS had a severe infection with eventual recovery.

CONCLUSIONS

Vaccination effectively protects pwMS from COVID-19. An increased risk of breakthrough infection was noted on high-efficacy DMTs, however COVID-19 after vaccination was usually mild.

COVID-19: The Course, Vaccination and Immune Response in People with Multiple Sclerosis: Systematic Review

When the Coronavirus Disease 2019 (COVID-19) appeared, it was unknown what impact it would have on the condition of patients with autoimmunological disorders. Attention was focused on the course of infection in patients suffering from multiple sclerosis (MS), specially treated with disease-modifying therapies (DMTs) or glucocorticoids. The impact of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection on the occurrence of MS relapses or pseudo-relapses was important. This review focuses on the risk, symptoms, course, and mortality of COVID-19 as well as immune response to vaccinations against COVID-19 in patients with MS (PwMS). We searched the PubMed database according to specific criteria. PwMS have the risk of infection, hospitalization, symptoms, and mortality due to COVID-19, mostly similar to the general population. The presence of comorbidities, male sex, a higher degree of disability, and older age increase the frequency and severity of the COVID-19 course in PwMS. For example, it was reported that anti-CD20 therapy is probably associated with an increased risk of severe COVID-19 outcomes. After SARS-CoV-2 infection or vaccination, MS patients acquire humoral and cellular immunity, but the degree of immune response depends on applied DMTs. Additional studies are necessary to corroborate these findings. However, indisputably, some PwMS need special attention within the context of COVID-19.

T cell responses to COVID-19 infection and vaccination in patients with multiple sclerosis receiving disease-modifying therapy

BACKGROUND

Multiple sclerosis (MS) is a neurological disorder marked by accumulating immune-mediated damage to the central nervous system. The dysregulated immune system in MS combined with immune effects of disease-modifying therapies (DMTs) used in MS treatment could alter responses to infections, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes coronavirus disease 2019 (COVID-19). Most of the literature on immune response to SARS-CoV-2 infection and COVID-19 vaccination, in both the general population and patients with MS on DMTs, has focused on humoral immunity. However, immune response to COVID-19 involves multiple lines of defense, including T cells.

OBJECTIVE AND METHODS

We review innate and adaptive immunity to COVID-19 and expand on the role of T cells in mediating protective immunity against SARS-CoV-2 infection and in responses to COVID-19 vaccination in MS.

RESULTS

Innate, humoral, and T cell immune responses combat COVID-19 and generate protective immunity. Assays detecting cytokine expression by T cells show an association between SARS-CoV-2-specific T cell responses and milder/asymptomatic COVID-19 and protective immune memory.

CONCLUSION

Studies of COVID-19 immunity in people with MS on DMTs should ideally include comprehensive assessment of innate, humoral, and T cell responses.

Short- and Long-Term Humoral and Cellular Immune Responses to SARS-CoV-2 Vaccination in Patients with Multiple Sclerosis Treated with Disease-Modifying Therapies

BACKGROUND

This study aimed to evaluate short- and long-term humoral and T-cell-specific immune responses to SARS-CoV-2 vaccines in patients with multiple sclerosis (MS) treated with different disease-modifying therapies (DMTs).

METHODS

Single-center observational longitudinal study including 102 patients with MS who consecutively received vaccination against SARS-CoV-2. Serum samples were collected at baseline and after receiving the second dose of the vaccine. Specific Th1 responses following in vitro stimulation with spike and nucleocapsid peptides were analyzed by quantifying levels of IFN-γ. Serum IgG-type antibodies against the spike region of SARS-CoV-2 were studied by chemiluminescent microparticle immunoassay.

RESULTS

Patients undergoing fingolimod and anti-CD20 therapies had a markedly lower humoral response than those treated with other DMTs and untreated patients. Robust antigen-specific T-cell responses were detected in all patients except those treated with fingolimod, who had lower IFN-γ levels than those treated with other DMTs (25.8 pg/mL vs. 868.7 pg/mL, p = 0.011). At mid-term follow-up, a decrease in vaccine-induced anti-SARS-CoV-2 IgG antibodies was observed in all subgroups of patients receiving DMTs, although most patients receiving induction DMTs or natalizumab and non-treated patients remained protected. Cellular immunity was maintained above protective levels in all DMT subgroups except the fingolimod subgroup.

CONCLUSIONS

SARS-CoV-2 vaccines induce robust and long-lasting humoral and cell-mediated specific immune responses in most patients with MS.

Effectiveness of BBIBP-CorV vaccine in preventing SARS-CoV2 infection and severe outcomes in people living with multiple sclerosis: A population-based study

BACKGROUND

The objective of the present study was to estimate the effectiveness of the BBIBP-CorV vaccine (VE) in preventing SARS-CoV-2 infection, related hospitalization, and death among people living with multiple sclerosis (PLWMS).

METHODS

In this population-based retrospective observational study, data on all PLWMS, vaccination, SARS-CoV-2 tests, hospitalization, and deaths were collected in Isfahan, Iran between February 9, 2021, and November 4, 2021. We estimated the hazard ratio between vaccinated (partially and fully) and unvaccinated groups using the Andersen-Gill extension of the Cox proportional hazards model. We also performed Cox proportional hazards analysis to identify risk factors for breakthrough infection and COVID-19-related hospitalization in fully-immunized group.

RESULTS

Of the 9869 PLWMS, 1368 were in partially-vaccinated group, 4107 were in the fully-vaccinated group, and 3794 were in the unvaccinated group. In the partially-vaccinated group, the estimated VE against COVID-19 infection was 39.3% (16%, 56.1%), hospitalization was 64.9% (1.3%, 87.5%), and mortality was 92.7% (88.8%, 100%). The respective results for the fully-vaccinated group were 63.9% (56%, 70.3%), 75.7% (57.5%, 86.1%), and 100%. Progressive MS was independently associated with a greater risk of breakthrough infection (HR=1.952, 95%CI: 1.174-3.246, p = 0.010). Older adults (≥50 years vs. 18-49 years, HR=3.115, 95%CI: 1.145-8.470, p = 0.026) and those on rituximab (HR=7.584; 95% CI: 1.864-30.854; p = 0.005) were at an increased risk of COVID-19-related hospitalization.

CONCLUSION

This study showed that two doses of the BBIBP-CorV vaccine can effectively prevent COVID-19 infection and hospitalization among PLWMS. Old PLWMS and those who treating with rituximab are at increased risk of hospitalization after receiving two doses of the vaccine.

Ocrelizumab Impairs the Phenotype and Function of Memory CD8+ T Cells: A 1-Year Longitudinal Study in Patients With Multiple Sclerosis

BACKGROUND AND OBJECTIVE

Depleting CD20⁺ B cells is the primary mechanism by which ocrelizumab (OCRE) is efficient in persons with multiple sclerosis (pwMS). However, the exact role of OCRE on other immune cell subsets directly or indirectly remains elusive. The purpose of this study is to characterize the dynamics of peripheral immune cells of pwMS on OCRE.

METHODS

We collected blood samples from 38 pwMS before OCRE onset (T0) and at 6 and 12 months (T6, T12) after initiation. To cover the immune cell diversity, using mass cytometry time of flight, we designed a 38-parameter panel to analyze B, T, and innate immune cell markers and CNS migratory markers. In parallel, viral-specific CD8⁺ T-cell responses were assessed by the quantification of interferon-γ secretion using the enzyme-linked immunospot assay on cytomegalovirus, Epstein-Barr virus, and influenza stimulations.

RESULTS

Beside B-cell depletion, we observed a loss in memory CD8⁺CD20⁺ and central memory CD8⁺ T cells but not in CD4⁺CD20⁺ T cells already at T6 and T12 (p < 0.001). The loss of memory CD8⁺ T cells correlated with a lower CXCR3 expression (p < 0.001) and CNS-related LFA-1 integrin expression (p < 0.001) as well as a reduced antiviral cellular immune response observed at both time points (p < 0.001). Of note, we did not observe major changes in the phenotype of the other cell types studied. Seven of 38 (18.4%) patients in our cohort presented with infections while on OCRE; 4 of which were switched from dimethyl fumarate. Finally, using a mixed linear model on mass cytometry data, we demonstrated that the immunomodulation induced by previous disease-modifying therapies (DMTs) was prolonged over the period of the study.

DISCUSSION

In addition to its well-known role on B cells, our data suggest that OCRE also acts on CD8⁺ T cells by depleting the memory compartment. These changes in CD8⁺ T cells may be an asset in the action of OCRE on MS course but might also contribute to explain the increased occurrence of infections in these patients. Finally, although more data are needed to confirm this observation, it suggests that clinicians should pay a special attention to an increased infection risk in pwMS switched from other DMTs to OCRE.

Ocrelizumab effect on humoral and cellular immunity in multiple sclerosis and its clinical correlates: a 3-year observational study

OBJECTIVE

We aim to evaluate 3-year effects of ocrelizumab (humanized anti-CD20 monoclonal antibody for the treatment of multiple sclerosis (MS)) on lymphocytes, neutrophils and immunoglobulins: (1) when compared with pre-infusion assessment; (2) over the course of treatment; and (3) possible clinical correlates of the observed immunological modifications.

METHODS

This real-world observational cohort study has been conducted on prospectively collected data from 78 MS patients (mean age 47.8 ± 10.5 years; females 48.7%) commencing on ocrelizumab from 2018, with mean follow-up of 36.5 ± 6.8 months. Clinical data and blood samples were collected every three months. Total lymphocyte count and subpopulations were assessed on peripheral blood using flow cytometry. Serum immunoglobulins were evaluated with nephelometry.

RESULTS

When compared with pre-infusion values, we observed reduction of total, CD19 and CD20 lymphocyte counts; however, after the first infusion, their levels remained substantially stable. Over time we observed a progressive reduction of CD8 lymphocytes, while no changes were observed for CD4, CD27, CD3CD27, and CD19CD27. After the first infusion, we observed reduction in IgG, which further decreased during the follow-up. Higher probability of EDSS progression was associated with reduced modulation of CD8 lymphocytes.

INTERPRETATION

Ocrelizumab affects both humoral and cellular immune responses. Disability progression over the follow-up was associated with lower CD8 cytotoxic T-lymphocyte reduction. Changes in humoral response are immediate and sustained, while modulation of cellular immunity occurs progressively through regular re-treatment, and is related to clinical stability.

Multiple Sclerosis Treatment in the COVID-19 Era: A Risk-Benefit Approach

The COVID-19 pandemic poses an ongoing global challenge, and several risk factors make people with multiple sclerosis (pwMS) particularly susceptible to running a severe disease course. Although the literature does report numerous articles on the risk factors for severe COVID-19 and vaccination response in pwMS, there is a scarcity of reviews integrating both these aspects into strategies aimed at minimizing risks. The aim of this review is to describe the risk of vulnerable pwMS exposed to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the issues related to the SARS-CoV-2 vaccine and to evidence possible future strategies in the clinical management of pwMS. The authors searched for papers on severe COVID-19 risk factors, SARS-CoV-2 vaccination and people with multiple sclerosis in support of this narrative literature review. We propose a multilevel strategy aimed at: the evaluation of risk factors for severe COVID-19 in people with multiple sclerosis, identifying the most appropriate vaccination schedule that is safe for people on disease-modifying drugs (DMDs) and a strict follow-up of high-risk people with multiple sclerosis to allow for the prompt administration of monoclonal antibodies to manage COVID-19 risks in this patient population.

Impact of immunotherapies on COVID-19 outcomes in multiple sclerosis patients

INTRODUCTION

SARS-CoV-2 pandemic has led the scientific community to maximize efforts to prevent infections and disease severity in patients with multiple sclerosis (pwMS). We analyze the impact of immunotherapies on COVID-19 outcomes in pwMS, providing our interpretation of data.

AREAS COVERED

Infections, hospitalizations, intensive care unit admissions and death rates in COVID-19 pwMS are comparable to general population. Severity of disability, MS clinical phenotype, age and comorbidities, along with the use of intravenous methylprednisolone and anti-CD20 treatments, are risk factors for COVID-19 severity. Disease modifying treatments (DMTs) can be safely started and continued during the pandemic. Benefit-risk evaluation is mandatory when managing second-line therapies, to balance risk of worse COVID-19 outcomes and MS reactivation. COVID-19 vaccination is safe in MS and its efficacy could be reduced in fingolimod and ocrelizumab-treated patients.

EXPERT OPINION

Rate of (re)-infection and outcomes with SARS-CoV-2 variants in pwMS and antiviral properties of DMTs need to be further explored. Data on COVID-19 in pregnant MS women, children and elderly pwMS are limited. Evidence on long-term effects of infection is needed. Impact of emerging DMTs on COVID-19 should be investigated. More data and longer follow-up are needed to characterize long-term efficacy and safety profile of vaccinations in pwMS.