Virus-mediated autoimmunity in Multiple Sclerosis

Epidemiological data suggest the notion that in Multiple Sclerosis (MS) is an acquired autoimmune disease and the cause may be an environmental factor(s), probably infectious, in genetically susceptible individuals. Several cases of viral induced demyelinatimg encephalomyelitis in human beings and in experimental models as well as the presence of IgG oligoclonal bands in the cerebrospinal fluid indicate that the infectious factor may be viral. However, the absence of a specific virus identification in MS central nervous system may hardly support this notion. On the other hand, the partial response of patients with MS to immunosuppressive and immunomodulatory therapy support the evidence of an autoimmune etiology for MS. However, the autoimmune hypothesis shares the same criticism with the infectious one in that no autoantigen(s) specific to and causative for MS has ever been identified. Nevertheless, the absence of identifiable infectious agent, especially viral does not rule out its presence at a certain time – point and the concomitant long term triggering of an autoimmune cascade of events thereafter. Several concepts have emerged in an attempt to explain the autoimmune mechanisms and ongoing neurodegeneration in MS on the basis of the infectious – viral hypothesis

Assessment of the sensitivity of anti-interferon binding and neutralizing antibody assays in patients with relapsing -remitting multiple sclerosis under interferon- beta treatment- A comparative study

Interferon beta (IFNβ) is a first line disease-modifying treatment for the management of relapsing-remitting multiple sclerosis. IFNβ preparations may elicit an immune response reflected by the development of binding- (Babs) and neutralizing- antibodies (Nabs). The detrimental effect of Nabs is depicted by attenuation of treatment effect and as a result the deterioration of clinical and radiological parameters. The incidence and titers of Nabs vary by the preparation of IFNβ used, dose, frequency and route of administration, treatment duration and type of assay being used. In this study we aimed to assess the sensitivity of the binding and the neutralizing assays in patients with relapsing-remitting multiple sclerosis under treatment with interferon-beta. The assessment of the results suggests that Western blot assay is more sensitive than ELISA for the detection of binding antibodies. The evaluation of CPE and Real-time-PCR results indicates that they possess similar sensitivity. However, CPE assay remains the gold standard method for the detection of neutralizing antibodies, based on the World Health Organization. Our results indicate that interlaboratory studies are needed for a commonly accepted assay that might reflect a reliable and cost-effective procedure for the Babs and Nabs detection in MS patients under IFNβ treatment

Morphological, histochemical, and interstitial pressure changes in the tibialis anterior muscle before and after aortofemoral bypass in patients with peripheral arterial occlusive disease

BACKGROUND: Morphological and electrophysiological studies of ischemic muscles in peripheral arterial disease disclosed evidence of denervation and fibre atrophy. The purpose of the present study is to describe morphological changes in ischemic muscles before and after reperfusion surgery in patients with peripheral occlusive arterial disease, and to provide an insight into the effect of reperfusion on the histochemistry of the reperfused muscle. METHODS: Muscle biopsies were obtained from the tibialis anterior of 9 patients with chronic peripheral arterial occlusive disease of the lower extremities, before and after aortofemoral bypass, in order to evaluate the extent and type of muscle fibre changes during ischemia and after revascularization. Fibre type content and muscle fibre areas were quantified using standard histological and histochemical methods and morphometric analysis. Each patient underwent concentric needle electromyography, nerve conduction velocity studies, and interstitial pressure measurements. RESULTS: Preoperatively all patients showed muscle fibre atrophy of both types, type II fibre area being more affected. The mean fibre cross sectional area of type I was 3,745 μm(2) and of type II 4,654 μm(2) . Fibre-type grouping, great variation in fibre size and angular fibres were indicative of chronic dennervation-reinnervation, in the absence of any clinical evidence of a neuropathic process. Seven days after the reperfusion the areas of both fibre types were even more reduced, being 3,086 μm(2) for type I and 4,009 μm(2) for type II, the proportion of type I fibres, and the interstitial pressure of tibialis anterior were increased. CONCLUSIONS: The findings suggest that chronic ischemia of the leg muscles causes compensatory histochemical changes in muscle fibres resulting from muscle hypoxia, and chronic dennervation-reinnervation changes, resulting possibly from ischemic neuropathy. Reperfusion seems to bring the oxidative capacity of the previously ischemic muscle closer to normal

How does Nogo receptor influence demyelination and remyelination in the context of multiple sclerosis?

Multiple sclerosis (MS) can progress with neurodegeneration as a consequence of chronic inflammatory mechanisms that drive neural cell loss and/or neuroaxonal dystrophy in the central nervous system. Immune-mediated mechanisms can accumulate myelin debris in the disease extracellular milieu during chronic-active demyelination that can limit neurorepair/plasticity and experimental evidence suggests that potentiated removal of myelin debris can promote neurorepair in models of MS. The myelin-associated inhibitory factors (MAIFs) are integral contributors to neurodegenerative processes in models of trauma and experimental MS-like disease that can be targeted to promote neurorepair. This review highlights the molecular and cellular mechanisms that drive neurodegeneration as a consequence of chronic-active inflammation and outlines plausible therapeutic approaches to antagonize the MAIFs during the evolution of neuroinflammatory lesions. Moreover, investigative lines for translation of targeted therapies against these myelin inhibitors are defined with an emphasis on the chief MAIF, Nogo-A, that may demonstrate clinical efficacy of neurorepair during progressive MS

Evaluation of the Possible Transmission of BSE and Scrapie to Gilthead Sea Bream (Sparus aurata)

In transmissible spongiform encephalopathies (TSEs), a group of fatal neurodegenerative disorders affecting many species, the key event in disease pathogenesis is the accumulation of an abnormal conformational isoform (PrPSc) of the host-encoded cellular prion protein (PrPC). While the precise mechanism of the PrPC to PrPSc conversion is not understood, it is clear that host PrPC expression is a prerequisite for effective infectious prion propagation. Although there have been many studies on TSEs in mammalian species, little is known about TSE pathogenesis in fish. Here we show that while gilthead sea bream (Sparus aurata) orally challenged with brain homogenates prepared either from a BSE infected cow or from scrapie infected sheep developed no clinical prion disease, the brains of TSE-fed fish sampled two years after challenge did show signs of neurodegeneration and accumulation of deposits that reacted positively with antibodies raised against sea bream PrP. The control groups, fed with brains from uninfected animals, showed no such signs. Remarkably, the deposits developed much more rapidly and extensively in fish inoculated with BSE-infected material than in the ones challenged with the scrapie-infected brain homogenate, with numerous deposits being proteinase K-resistant. These plaque-like aggregates exhibited congophilia and birefringence in polarized light, consistent with an amyloid-like component. The neurodegeneration and abnormal deposition in the brains of fish challenged with prion, especially BSE, raises concerns about the potential risk to public health. As fish aquaculture is an economically important industry providing high protein nutrition for humans and other mammalian species, the prospect of farmed fish being contaminated with infectious mammalian PrPSc, or of a prion disease developing in farmed fish is alarming and requires further evaluation

Multiple sclerosis and mental health related quality of life: The role of defense mechanisms, defense styles and family environment

Background: Multiple sclerosis is a demyelinating chronic neurologic disease that can lead to disability and thus to deterioration of quality of life. Psychological parameters such as ego defense mechanisms, defense styles and family environment are important factors in the adaptation process, and as such they can play important roles in QoL. This study aims to assess the psychological factors as well as the clinical and demographic characteristics related to mental health quality of life (MHQoL). Methods: This was an observational, cross-sectional study conducted in a sample of 90 people with MS in the years 2018–2020. All participants completed the following questionnaires: MSQoL-54, DSQ-88, LSI, FES-R, SOC, BDI-II, STAI. Disability was assessed using EDSS. Results:In multiple linear regression, significant roles were played by depression (R2: 41.1%, p: 0.001) and, to a lesser extent, the event of a relapse (R2: 3.5%, p: 0.005), expressiveness (R2: 3.6%, p < 0.05) and image distortion style (R2: 4.5%, p: 0.032). After performing a hierarchical-stepwise analysis (excluding depression), the important factors were maladaptive defense style (R2: 23.7%, p: 0.002), the event of relapse (R2: 8.1%, p < 0.001), expressiveness (R2: 5.5%, p: 0.004) and self-sacrificing defense style (R2: 2.4%, p: 0.071). Conclusion: Psychological factors play important roles in MHQoL of people with multiple sclerosis. Thus, neurologists should integrate in their practice an assessment by mental health specialists. Moreover, targeted psychotherapeutic interventions could be planned i to improve QoL

Anti-SARS-CoV-2 vaccination in people with multiple sclerosis: Lessons learnt a year in.

It has been over a year since people with multiple sclerosis (pwMS) have been receiving vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). With a negligible number of cases in which vaccination led to a relapse or new onset MS, experts around the world agree that the potential consequences of COVID-19 in pwMS by far outweigh the risks of vaccination. This article reviews the currently available types of anti-SARS-CoV-2 vaccines and the immune responses they elicit in pwMS treated with different DMTs. Findings to date highlight the importance of vaccine timing in relation to DMT dosing to maximize protection, and of encouraging pwMS to get booster doses when offered