RESUMO
Multiple sclerosis (MS) is a disease of the central nervous system (CNS) that is the result of the body's own immune cells being auto-reactive to the myelin regions of the body as if these regions were foreign antigens. This demyelination process is damaging to the electrical conductivity of neurons. The current medicines are only capable of fighting off the symptoms of the disease, but not the disease itself. Specialized stem cells, known as mesenchymal stem cells (MSCs), seem to be the candidate therapy to get rid of MS. MSCs can be isolated from multiple sources of the person's body, and even from the umbilical cord (UC) and placenta of a donor. These cells have anti-inflammatory effects so they can target the overactivity and self-antigen attacks by T cells and macrophages; this immune system overactivity is characteristic of MS. MSCs show the ability to locate into brain lesions when injected and thus can compensate for the loss of the brain function by differentiating into neuronal precursor cells and glial cells. The author has listed tables of clinical trials that have utilized MSCs from different sources, along with the years and the phase of study completed for each trial. The consensus is that these cells work on inhibiting CD4+ and CD8+ T cell activation, T regulatory cells (Tregs), and macrophage switch into the auto-immune phenotype. The best source of MSCs seems to be the UC due to the easiness of extraction, the noninvasive method of collection, their higher expansion ability and more powerful immune-modulating properties compared to other locations in the body. Studies showed there was a significant decline of mRNA expression of several cytokines after the administration of MSCs derived from the UC (UCMSCs). Other researchers were able to repair the defects of Tregs in MS patients by co-culturing Tregs from these patients with UCMSCs, which decreased the production of the pro-inflammatory cytokine IFN γ , and also suggested a strong link between Tregs lack of functionality in MS patients with the pathogenesis of the disease.
RESUMO
BACKGROUND: The outbreak of coronavirus disease 2019 (COVID-19) has rapidly spread and developed as a pandemic threatening global health. Patients with multiple sclerosis (MS)-an autoimmune demyelinating inflammatory disease of the central nervous system (CNS)-are predominantly treated with immunomodulatory/immunosuppressive disease-modifying therapies (DMTs), which can increase the risk of infection. Therefore, there is concern that these patients may have a higher risk of COVID-19. In response to growing concerns of neurologists and patients, this study aimed to determine the prevalence, severity, and possible complications of COVID-19 infection in patients with MS in Saudi Arabia (SA). METHODS: In this prospective cohort study, demographic and clinical data were obtained from patients residing in SA with MS who had a positive result for COVID-19 per reverse transcription-polymerase chain reaction test or viral gene sequencing, using respiratory or plasma samples. Comparison of COVID-19 severity groups was performed using one-way ANOVA or Kruskal-Wallis test for numerical variables and Chi-squared test for categorical variables. RESULTS: Seventy patients with MS and COVID-19 (71% female) were included in this analysis. Of the 53 (75.7%) patients receiving a DMT at the time of COVID-19 infection, the most frequently used DMTs were fingolimod (25%) and interferon-beta (25%). Nine (13%) patients had MS relapse and were treated with intravenous methylprednisolone in the four weeks before COVID-19 infection. The most common symptoms at the peak of COVID-19 infection were fever (46%), fatigue (37%), and headache (36%). Symptoms lasted for a mean duration of 8.7 days; all symptomatic patients recovered and no deaths were reported. COVID-19 severity was categorized in three groups: asymptomatic (n = 12), mild-not requiring hospitalization (n = 48), and requiring hospitalization (n = 10; two of whom were admitted to the intensive care unit [ICU]). Between the three groups, comparison of age, body mass index , Expanded Disability Severity Score , MS disease duration, and DMT use at the time of infection showed no significant differences. A higher percentage of patients who were admitted to hospital or the ICU (40%; p = 0.026) presented with an MS relapse within the prior four weeks compared with those who were asymptomatic or had a mild infection (both 8.3%). CONCLUSION: These findings present a reassuring picture regarding COVID-19 infection in patients with MS. However, patients with MS who have had a relapse in the preceding four weeks (requiring glucocorticoid treatment) may have an increased risk of severe COVID-19.