Practical recommendations on treatment of multiple sclerosis with Cladribine: an Israeli Experts Group Viewpoint.

Cladribine tablets (Mavenclad®) were approved by the European Union in 2017 as high-efficacy therapy for highly active relapsing-remitting multiple sclerosis. In Israel, Mavenclad® was approved in 2018. Real-life experience has confirmed the efficacy of cladribine tablets over at least 4 years from the initial course. During the last years, several questions were raised concerning the management of people with MS who show disease activity during years 3 and 4 post-cladribine initiation and what treatment decisions are needed beyond year 4. A few expert boards have tried to provide insight based on research data and to suggest recommendations on the therapeutic dilemmas and treatment decisions with cladribine. However, there is currently no widely accepted consensus about these issues. The vast clinical experience gained in Israel in the past 5 years in several MS centers across the country allows for a broad perspective of the outcomes with long-term cladribine use. This article summarizes previously published recent recommendations and describes the insights of Israeli neurology key opinion leaders that convened for an advisory board meeting on January 29th, 2023, with the aim of reaching a consensus regarding cladribine long-term treatment and follow-up.

A case report of unilateral cervical lymphadenopathy and multiple cranial neuropathies following mRNA-COVID-19 vaccination.

BACKGROUND: We report a rare case of ipsilateral multiple cranial neuropathy and ipsilateral lymphadenopathy following mRNA-COVID-19 vaccination. CASE PRESENTATION: A 41-year-old male visited our emergency room complaining of dysphagia and hoarseness that started a week after receiving COVID19 mRNA vaccination (in his right arm). During his hospitalization, he also complained of right side hearing loss and diplopia. Neurological examination depicted a right IV nerve palsy, ipsilateral facial paresthesia and peripheral facial paresis. Otorinolaryngological examination revealed right vocal cord paralysis. A brain magnetic resonance imaging showed enhancement of the right VII and VIII cranial nerves in the auditory canal. The lumbar puncture revealed increased protein concentration and lymphocytic pleocytosis in the cerebrospinal fluid (CSF). Additionally, a neck computed tomography (CT) scan showed a swollen right supraclavicular lymph node. We hypothesize that the ipsilateral cranial neuropathies of IV, VI, VII, VIII and X, associated with cervical lymphadenopathy, was possible caused by a post-vaccination immune-mediated reaction. The patient was treated with a 5-day course of intravenous methylprednisolone (1000 mg/day), and a gradual improvement was observed. CONCLUSIONS: Similarly, to other vaccines, it is possibly that also mRNA vaccines may act as triggers of non-specific autoimmune neurological syndromes.

Effects of Mesenchymal Stem Cell Transplantation on Cerebrospinal Fluid Biomarkers in Progressive Multiple Sclerosis.

BACKGROUND: Neurofilament light chains (NF-L) were shown to serve as a reliable biomarker of neurodegeneration in multiple sclerosis (MS). The chemokine receptor CXCL13 was shown to correlate with CNS inflammatory activity and to predict the future progression of MS. OBJECTIVE: To evaluate the levels of NF-L and CXCL13 in the cerebrospinal fluid (CSF) following treatment with mesenchymal stem cells (MSC) in patients with progressive MS. METHODS: The CSF samples were obtained from 48 patients with progressive MS who participated in a double-blind randomized phase II clinical trial that tested the effects of intrathecal (IT) or intravenous (IV) transplantation of mesenchymal stem cells (MSC), at baseline (before the first injection of the MSC) and at 6 months following treatment with MSC, or sham treatment. The CSF specimens were tested in a blinded way, using a single-molecule array (SIMOA) technique. FINDINGS: The CSF levels of NF-L were significantly lower at 6 months following treatment with MSC-IT when compared with the baseline, pre-treatment measurements (P = .026, Wilcoxon paired test). Nine out of 15 tested patients in the MSC-IT group had a reduction in NF-L levels of more than 50% (median decrease: -4449 pg/mL) when compared with 5/15 in the MSC-IV group (median decrease: -151 pg/mL) and 1/15 in the placebo group (median increase: +2450 pg/mL) (P = .001 for MSC-IT vs. placebo, chi-square test). CXCL13 levels were also reduced at 6 months following MSC-IT treatment but not to a statistically significant level. CONCLUSIONS: Our findings indicate possible neuroprotective effects of MSC transplantation in patients with MS. CLINICAL TRIAL REGISTRATION: NCT02166021.

Humoral and Cellular Immune Responses to SARS-CoV-2 mRNA Vaccination in Patients with Multiple Sclerosis: An Israeli Multi-Center Experience Following 3 Vaccine Doses.

Background: Immunomodulatory/immunosuppressive activity of multiple sclerosis (MS) disease modifying therapies (DMTs) might affect immune responses to SARS-CoV-2 exposure or vaccination in patients with MS (PwMS). We evaluated the effect of DMTs on humoral and cell-mediated immune responses to 2 and 3 vaccinations and the longevity of SARS-Cov-2 IgG levels in PwMS. Methods: 522 PwMS and 68 healthy controls vaccinated with BNT162b2-Pfizer mRNA vaccine against SARS-CoV-2, or recovering from COVID-19, were recruited in a nation-wide multi-center study. Blood was collected at 3 time-points: 2-16 weeks and ~6 months post 2nd vaccination and 1-16 weeks following 3rd vaccination. Serological responses were measured by quantifying IgG levels against the spike-receptor-binding-domain of SARS-CoV-2, and cellular responses (in a subgroup analysis) by quantifying IFNγ secretion in blood incubated with COVID-19 spike-antigen. Results: 75% PwMS were seropositive post 2nd or 3rd vaccination. IgG levels decreased by 82% within 6 months from vaccination (p<0.0001), but were boosted 10.3 fold by the 3rd vaccination (p<0.0001), and 1.8 fold compared to ≤3m post 2nd vaccination (p=0.025). Patients treated with most DMTs were seropositive post 2nd and 3rd vaccinations, however only 38% and 44% of ocrelizumab-treated patients and 54% and 46% of fingolimod-treated patients, respectively, were seropositive. Similarly, in COVID-19-recovered patients only 54% of ocrelizumab-treated, 75% of fingolimod-treated and 67% of cladribine-treated patients were seropositive. A time interval of ≥5 months between ocrelizumab infusion and vaccination was associated with higher IgG levels (p=0.039 post-2nd vaccination; p=0.036 post-3rd vaccination), and with higher proportions of seropositive patients. Most fingolimod- and ocrelizumab-treated patients responded similarly to 2nd and 3rd vaccination. IFNγ-T-cell responses were detected in 89% and 63% of PwMS post 2nd and 3rd vaccination, however in only 25% and 0% of fingolimod-treated patients, while in 100% and 86% of ocrelizumab-treated patients, respectively. Conclusion: PwMS treated with most DMTs developed humoral and T-cell responses following 2 and 3 mRNA SARS-CoV-2 vaccinations. Fingolimod- or ocrelizumab-treated patients had diminished humoral responses, and fingolimod compromised the cellular responses, with no improvement after a 3rd booster. Vaccination following >5 months since ocrelizumab infusion was associated with better sero-positivity. These findings may contribute to the development of treatment-stratified vaccination guidelines for PwMS.

Anatomical and functional visual network patterns in progressive multiple sclerosis.

The gradual accrual of disability over time in progressive multiple sclerosis is believed to be driven by widespread degeneration. Yet another facet of the problem may reside in the loss of the brain's ability to adapt to the damage incurred as the disease progresses. In this study, we attempted to examine whether changes associated with optic neuritis in the structural and functional visual networks can still be discerned in progressive patients even years after the acute insult. Forty-eight progressive multiple sclerosis patients, 21 with and 27 without prior optic neuritis, underwent structural and functional MRI, including DTI and resting state fMRI. Anatomical and functional visual networks were analyzed using graph theory-based methods. While no functional metrics were significantly different between the two groups, anatomical global efficiency and density were significantly lower in the optic neuritis group, despite no significant difference in lesion load between the groups. We conclude that long-standing distal damage to the optic nerve causes trans-synaptic effects and the early ability of the cortex to adapt may be altered, or possibly nullified. We suggest that this limited ability of the brain to compensate should be considered when attempting to explain the accumulation of disability in progressive multiple sclerosis patients.

A phase II clinical trial with repeated intrathecal injections of autologous mesenchymal stem cells in patients with amyotrophic lateral sclerosis.

Background: Mesenchymal stem cells (MSC) were shown to induce beneficial effects in animal models of neurodegeneration and in pilot human trials in multiple sclerosis and amyotrophic lateral sclerosis (ALS). Aim: An open-label, clinical trial to evaluate the safety and efficacy of repeated intrathecal administrations of autologous-MSC in ALS-patients. Methods: The study included 20 subjects (age: 20-70) with definite diagnosis of ALS and Amyotrophic Lateral Sclerosis Functional Rating Scale Revised (ALSFRS-R) score of >20. The patients were treated with 1-4 intrathecal injections of MSC, at intervals of 3-6 months. The primary endpoints were safety and tolerability. Efficacy measurements including ALSFRS-R score and forced vital capacity (FVC), were assessed as secondary endpoints. Results: No serious adverse events were observed during the whole period of the trial. One patient withdrew from the study before the first injection. The monthly rate of progression in ALSFRS-R was ameliorated by more than 25% in 15/19 patients between the 1st and 2nd injection (mean improvement of 107.1%); in 11/12 between the 2nd and 3rd injection and in 8/10 between the 3rd and 4th injection. Overall, during the whole period till the last transplantation 13 patients had a >25% improvement in the slope of progression of ALSFRS-R (mean improvement of 47.4%, p < 0.0038, Wilcoxon rank signed test). 7 out of 19 patients actually improved clinically (range of increase in ALSFRS-R: +1 to +4 degrees) after the first transplantation and 5 remained improved after the second cycle. The response rate correlated with the time-intervals between the injections. Conclusion: The results of our study show that repeated intrathecal injections of autologous MSC was safe in patients with ALS and provide indications of medium-term clinical benefits that were related to the intervals between the administrations of the cells. Larger studies are needed to confirm these observations.

Beneficial effects of a nano formulation of pomegranate seed oil, GranaGard, on the cognitive function of multiple sclerosis patients.

BACKGROUND: Though often neglected, cognitive impairment is a common feature of multiple sclerosis in 43-70% of patients. None of the novel MS treatment seems to substantially affect or restore cognitive disability in MS. GranaGard (Granalix Bio Technologies LTD) is a food supplement shown to prevent neuronal death in several animal models of neurological diseases. Capsules of GranaGard comprise a self-emulsion nano formulation of pomegranate seed oil (PSO). This oil contains 80-90% of Punicic Acid (PA), one of the strongest natural antioxidants. In animal experiments, administration of GranaGard results in conjugation with linoleic acid (CLA), the main metabolite of PA, which is a well-known neuroprotective agent. AIMS: To investigate whether GranaGard administration has an effect on the cognitive state of MS patients. METHODS: This is a single center, randomized double blind clinical trial that started in May 2018. The study included 30 MS patients; half of them (Group-A) were given GranaGard for the first three months and then placebo pills containing soybean oil for additional three months. Patients in Group-B received placebo for the first three months, and GranaGard for the following three months. GranaGard was administrated in addition to their immunomodulatory MS-treatments. Subsequently, all patients received GranaGard for additional six months. Patients were required to visit the neurologist at baseline (inclusion, visit 1) and at 3 months after treatment-initiation at each cycle of the trial (visits 2 and 3). During the follow up visits, clinical and cognitive examinations were performed, including Expanded Disability Status Scale (EDSS), Multiple Sclerosis Functional Composite (MSFC: 25 ft walking test, 9 PEG hole test & PASAT). Cognitive tests included The Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS) battery: 1) Symbol Digit Modalities Test (SDMT); 2) California Verbal Learning Test - Second Edition (CVLT-II); 3) and Brief Visuospatial Memory Test - Revised (BVMT-R). Cognitive outcomes were normalized to the healthy population and expressed as z-scores, depended on age, gender and education. Short quality of life and fatigue questionnaires (SF-12, MFIS-5) were also provided by the participants. RESULTS: No serious adverse effects, related to the product, were observed during the study period. All patients receiving GranaGard reported a ''positive'' effect in their ADL while using the product. While there were no significant differences in the clinical parameters of disability (EDSS scores) between the treatment groups, there was a trend of beneficial effect of GranaGard, on the verbal testing during the first 3-month period of treatment. The z score for CVLT-II, significantly increased (from 0.891 to 1.415, p = 0.012, Wilcoxon rank test) at 3-months in the group of patients who were treated with GranaGard, as compared to baseline. A similar (but not statistically significant) trend was seen also in the BVMTr testing during the same 3 months-period, whereas there was no change in the SDMT. The overall average z-score of all three cognitive functions was significantly improved in the three months of Granagard treatment (-0.0077 at 3 months vs 0.462 at baseline, p = 0.034, Wilcoxon rank test). During the same 3-months period there were no significant changes in the placebo-treated group. For the patients receiving GranaGard in the initial 3 months, the value of z score of CVLT-II remained high (z = 1.415) also at the following three months (while they received placebo), suggesting a longer lasting effect for at least 3 months after discontinuation of the drug. CONCLUSION: This is the first study in which GranaGard, a brain targeted nano-formulation of PSO, was tested in humans. Our results in this small pilot, controlled trial provide indications that GranaGard administration to MS patients might improve/stabilize cognitive disability. Larger studies with longer duration, are needed to confirm these initial observations.

Long-Term Clinical and Immunological Effects of Repeated Mesenchymal Stem Cell Injections in Patients With Progressive Forms of Multiple Sclerosis.

Background: Mesenchymal stem cells (MSC) were shown to possess immunomodulatory and neurotrophic effects. Our previous trials, have shown that intrathecal (IT) and intravenous (IV) administration of MSCs were safe and provided indications of beneficial clinical effects. Methods: This is an open prospective study to evaluate the safety and the long-term clinical and immunological effects of multiple injections of autologous MSCs in 24 patients with active-progressive MS. At inclusion, the mean age of the patients was 47.0 ± 9.22, and the mean EDSS score was 6.75 ± 0.68 (range: 5.5-7.5). Patients were initially treated with 1 ×106 MSCS/kg of body weight (IT + IV) and subsequently with up to additional eight courses of MSCs, at intervals of 6-12 months. The duration of the trial was 4 years. Results: No serious, treatment-related adverse events were observed during the follow-up period. Twenty-two of the 24 patients were either stable or improved at the last follow-up visit. Ten patients had a lower than baseline EDSS at the last follow-up (nine were among those who received >2 treatments and one in the subgroup of ≤ 2 treatments, p = 0.04). The mean EDSS score reduced from 6.75 ± 0.68 at baseline to 6.42 ± 0.84 at the last visit, during a median follow-up period of 27.8 months (p = 0.028). Immunological follow-up showed a transient upregulation of CD4+CD25+FoxP3+ cells and downregulation of the proliferative ability of lymphocytes. Conclusions: Repeated MSC treatments in patients with progressive MS were shown safe at the short/intermediate term and induced clinical benefits (especially in patients treated with >2 injections) that lasted for up to 4 years, paralleled by short-term immunomodulatory effects. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT04823000.

Synergistic neuroprotective effects of Fingolimod and mesenchymal stem cells (MSC) in experimental autoimmune encephalomyelitis.

Fingolimod (Gilenya™) is an effective oral medication approved for relapsing-remitting multiple sclerosis (MS), albeit less effective in chronic disease. Its main mechanism of action is through peripheral immunomodulation but neuroprotective effects may also be involved. Mesenchymal stem cells (MSC) were shown to exert immunomodulatory and neurotrophic effects in the model of multiple sclerosis (experimental autoimmune encephalomyelitis-EAE). The use of combination treatments in chronic diseases such as MS, has long been advocated and may result in improvement of the beneficial effects of each one of them. We tested the in vitro effects of Fingolimod (FTY720) on MSC and the in vivo effect of such combination treatment in the model of EAE. Fingolimod did not affect in any detrimental way the basic features of MSCs and it promoted their migration and proliferation ability .Moreover, Fingolimod induced neurotrophic factors secretion and suppressed the production of pro-inflammatory cytokines from astrocytes and microglia, in vitro. In vivo, the combined treatment of FTY720 and MSC (either by the intravenous or the intra-cerebroventricular route of administration) resulted in synergistic clinical beneficial effects compared to FTY720 or MSC alone, paralleled by a significant reduction of inflammatory CNS infiltrations and of axonal loss. These data may indicate a synergism of fingolimod with MSC and may support future combinations of immunomodulatory drugs with cellular therapies for the improvement of the benefits in progressive forms of MS.

Beneficial effects of autologous mesenchymal stem cell transplantation in active progressive multiple sclerosis.

In this study (trial registration: NCT02166021), we aimed to evaluate the optimal way of administration, the safety and the clinical efficacy of mesenchymal stem cell (MSC) transplantation in patients with active and progressive multiple sclerosis. Forty-eight patients (28 males and 20 females) with progressive multiple sclerosis (Expanded Disability Status Scale: 3.0-6.5, mean : 5.6 ± 0.8, mean age: 47.5 ± 12.3) and evidence of either clinical worsening or activity during the previous year, were enrolled (between 2015 and 2018). Patients were randomized into three groups and treated intrathecally (IT) or intravenously (IV) with autologous MSCs (1 × 106/kg) or sham injections. After 6 months, half of the patients from the MSC-IT and MSC-IV groups were retreated with MSCs, and the other half with sham injections. Patients initially assigned to sham treatment were divided into two subgroups and treated with either MSC-IT or MSC-IV. The study duration was 14 months. No serious treatment-related safety issues were detected. Significantly fewer patients experienced treatment failure in the MSC-IT and MSC-IV groups compared with those in the sham-treated group (6.7%, 9.7%, and 41.9%, respectively, P = 0.0003 and P = 0.0008). During the 1-year follow-up, 58.6% and 40.6% of patients treated with MSC-IT and MSC-IV, respectively, exhibited no evidence of disease activity compared with 9.7% in the sham-treated group (P < 0.0001 and P < 0.0048, respectively). MSC-IT transplantation induced additional benefits on the relapse rate, on the monthly changes of the T2 lesion load on MRI, and on the timed 25-foot walking test, 9-hole peg test, optical coherence tomography, functional MRI and cognitive tests. Treatment with MSCs was well-tolerated in progressive multiple sclerosis and induced short-term beneficial effects regarding the primary end points, especially in the patients with active disease. The intrathecal administration was more efficacious than the intravenous in several parameters of the disease. A phase III trial is warranted to confirm these findings.

Conduction delays in the visual pathways of progressive multiple sclerosis patients covary with brain structure.

In developed countries, multiple sclerosis (MS) is the leading cause of non-traumatic neurological disability in young adults. MS is a chronic demyelinating disease of the central nervous system, in which myelin is attacked, changing white matter structure and leaving lesions. The demyelination has a direct effect on white matter conductivity. This effect can be examined in the visual system, where damage is highly prevalent in MS, leading to substantial delays in conduction, commonly measured with visual evoked potentials (VEPs). The structural damage to the visual system in MS is often estimated with MRI measurements in the white matter. Recent developments in quantitative MRI (qMRI) provide improved sensitivity to myelin content and new structural methods allow better modeling of the axonal structure, leading researchers to link white matter microstructure to conduction properties of action potentials along fiber tracts. This study attempts to explain the variance in conduction latencies down the visual pathway using structural measurements of both the retina and the optic radiation (OR). Forty-eight progressive MS patients, participants in a longitudinal stem-cell therapy clinical trial, were included in this study, three and six months post final treatment. Twenty-seven patients had no history of optic neuritis, and were the main focus of this study. All participants underwent conventional MRI scans, as well as diffusion MRI and qMRI sequences to account for white matter microstructure. Optical coherence tomography scans were also obtained, and peripapillary retinal nerve fiber layer (pRNFL) thickness and macular volume measurements were extracted. Finally, latencies of recorded VEPs were estimated. Our results show that in non-optic neuritis progressive MS patients there is a relationship between the VEP latency and both retinal damage and OR lesion load. In addition, we find that qMRI values, sampled along the OR, are also correlated with VEP latency. Finally, we show that combining these parameters using PCA we can explain more than 40% of the inter-subject variance in VEP latency. In conclusion, this study contributes to understanding the relationship between the structural properties and conduction in the visual system in disease. We focus on the visual system, where the conduction latencies can be estimated, but the conclusions could be generalized to other brain systems where the white matter structure can be measured. It also highlights the importance of having multiple parameters when assessing the clinical stages of MS patients, which could have major implications for future studies of other white matter diseases.

Cerebrospinal Fluid (CSF) Exchange Therapy with Artificial CSF Enriched with Mesenchymal Stem Cell Secretions Ameliorates Cognitive Deficits and Brain Pathology in Alzheimer's Disease Mice.

BACKGROUND: The high complexity of neurodegenerative diseases, including Alzheimer's disease (AD), and the lack of effective treatments point to the need for a broader therapeutic approach to target multiple components involved in the disease pathogenesis. OBJECTIVE: To test the efficacy of 'cerebrospinal fluid (CSF) exchange therapy' in AD-mice. This novel therapeutic approach we recently proposed is based on the exchange of the endogenous pathogenic CSF with a new and healthy one by drainage of the endogenous CSF and its continuous replacement with artificial CSF (aCSF) enriched with secretions from human mesenchymal stem cells (MSCs). METHODS: We treated AD-mice (amyloid-beta injected) with MSC secretions-enriched-aCSF using an intracerebroventricular CSF exchange procedure. Cognitive and histological analysis were performed. RESULTS: We show that the MSC secretions enriched CSF exchange therapy improved cognitive performance, paralleled with increased neuronal counts (NeuN positive cells), reduced astrocytic burden (GFAP positive cells), and increased cell proliferation and neurogenesis (Ki67 positive cells and DCX positive cells) in the hippocampus. This beneficial effect was noted on days 5-10 following 3-consecutive daily exchange treatments (3 hours a day). A stronger effect was noted using a more prolonged CSF exchange protocol (3-consecutive daily exchange treatments with 3 additional treatments twice weekly), with cognitive follow-up performed as early as 2-3 days after treatment. Some increase in hippocampal cell proliferation, but no change in the other histological parameters, was noticed when performing CSF exchange therapy using unenriched aCSF relative to untreated AD-mice, yet smaller than with the enriched aCSF treatment. CONCLUSION: These findings point to the therapeutic potential of the CSF exchange therapy using MSC secretions-enriched aCSF in AD, and might be applied to other neurodegenerative and dementia diseases.

[MULTIPLE SCLEROSIS THERAPY - 2019].

INTRODUCTION: Multiple sclerosis (MS) is a chronic inflammatory-demyelinating and neurodegenerative disease of the central nervous system (CNS) of a putative autoimmune origin. The disease is characterized pathologically by scattered areas of peri-vascular mononuclear cell infiltrates, demyelination with various degrees of remyelination, axonal loss and gliosis that form multiple plaques throughout the brain and spinal cord, and clinically by a variety of neurological signs and symptoms disseminated in time and space. A better understanding of the immune pathogenesis of MS has led to the development of a variety of disease-modifying drugs (DMTs) capable of suppressing disease activity and reducing relapse rate and disability progression. The first injectable drugs included 3 forms of recombinant interferon-beta and glatiramer acetate. These "first line" therapies show modest but sustained effect on clinical disease activity and a favorable long-term safety profile. Several newer oral and biological drugs having various mechanisms of action have recently been introduced for MS. They demonstrate higher efficacy but harbor new, sometimes serious adverse events and risks that may limit their use and require thorough patient selection and strict safety monitoring programs. The impact of MS drugs on disease activity and appreciation of the irreversible brain damage that occurs from disease onset have led to the adoption of modern paradigms in MS therapy which include early, effective and personalized treatment, targeting towards a complete cessation of any disease activity ("no evidence of disease activity- NEDA"). This review aims to: 1. Describe current and promising future immunomodulatory drugs for MS and their place in the treatment of various forms of MS, based on the understanding of their mechanisms of action and effect on the immuno-pathological processes that lead to the damage in MS; and 2. provide guidance on individualized treatment selection based on modern paradigms of MS management.

Neuralized mesenchymal stem cells (NMSC) exhibit phenotypical, and biological evidence of neuronal transdifferentiation and suppress EAE more effectively than unmodified MSC.

In the last decade several studies employing stem cells-based therapies have been investigated as an optional treatment for multiple sclerosis. Several preclinical and few clinical studies tested the efficacy of mesenchymal stem cells as a potent candidate for such therapies. Here we suggest the option of "neuralization" of classical mesenchymal stem cells as a cellular structure that resembles neural stem cells as well as there differentiation by a unique procedure towards terminally differentiated neural cells suggesting that this cell population may be appropriate for clinical application in the CNS. We investigated whether neuralized MSC (NMSC) could promote repair and recovery after injection into mice with EAE. Injection of NMSC and differentiated NMSC starting at the onset of the chronic phase of disease improved neurological function compared to controls as well as compared to naïve MSC. Injection of NMSC and mainly differentiated correlated with a reduction in the inflammation as well as in the axonal loss/damage and reduced area of demyelination. These observations suggest that NMSC and differentiated NMSC may suggest a more potent cell-based therapy that naïve MSC in the treatment arsenal of multiple sclerosis.

Vision and Vision-Related Measures in Progressive Multiple Sclerosis.

Background: Over the last few years there has been growing interest in use of visual measures as useful tools for multiple sclerosis (MS) prognosis and tracking. Optic neuritis (ON) being a prevalent and often-presenting symptom of the disease, as well as the high occurrence rate of posterior visual system damage independent of ON (optic radiation lesions), make the visual system a prime candidate for such endeavors. However, while the visual system makes for a convenient model in early stages of MS, processes which may be true in those stages may drastically change as the disease progresses, due to accumulated disease load. Here, we examine whether vision-related tools reflect demyelinative and axonal damage of the visual pathways and may be used for assessment in the clinical setup in progressive multiple sclerosis (MS) patients, in whom disease load may alter the early stage picture. Methods: Forty-eight progressive MS patients, with and without prior optic neuritis (ON), underwent a battery of behavioral tests, visual evoked potential (VEP) tests, optical coherence tomography (OCT), and structural MRI scans, at two time-points. Data were analyzed for stability between visits and for correlation between behavioral and electrophysiological data. Results: All measures were stable between visits. Significant differences were found in all measures between the affected and fellow eyes of ON patients and in VEP latencies between the affected and non-ON eyes. Motion perception differentially correlated with latencies of both ON eyes and with the non-ON eyes. Retinal nerve fiber layer thickness correlated with the latencies of non-ON eyes but not of either ON eye. No difference in lesion load was found between the ON and non-ON patients. Conclusions: ON still leaves its mark in the patient's visual system over time, with all visual measures of the affected eyes notably reduced compared to fellow eyes. Motion perception, reflecting myelination level along the visual pathway, shows its usefulness also in progressive MS. In the non-ON eyes, axonal loss appears to explain prolonged latencies, unlike in ON eyes, where demyelination appears to be the main mechanism. Lastly, the visual measures assessed herein are applicable as valid assessment tools in therapeutic studies.

Cerebrospinal Fluid (CSF) Exchange with Artificial CSF Enriched with Mesenchymal Stem Cell Secretions Ameliorates Experimental Autoimmune Encephalomyelitis.

The complexity of central nervous system (CNS) degenerative/inflammatory diseases and the lack of substantially effective treatments point to the need for a broader therapeutic approach to target multiple components involved in the disease pathogenesis. We suggest a novel approach directed for the elimination of pathogenic agents from the CNS and, in parallel, its enrichment with an array of neuroprotective substances, using a "cerebrospinal fluid (CSF) exchange" procedure, in which endogenous (pathogenic) CSF is removed and replaced by artificial CSF (aCSF) enriched with secretions of human mesenchymal stem cells (MSCs). MSCs produce a variety of neuroprotective agents and have shown beneficial effects when cells are transplanted in animals and patients with CNS diseases. Our data show that MSCs grown in aCSF secrete neurotrophic factors, anti-inflammatory cytokines, and anti-oxidant agents; moreover, MSC-secretions-enriched-aCSF exerts neuroprotective and immunomodulatory effects in neuronal cell lines and spleen lymphocytes. Treatment of experimental-autoimmune-encephalomyelitis (EAE) mice with this enriched-aCSF using an intracerebroventricular (ICV) CSF exchange procedure ("CSF exchange therapy") caused a significant delay in the onset of EAE and amelioration of the clinical symptoms, paralleled by a reduction in axonal damage and demyelination. These findings point to the therapeutic potential of the CSF exchange therapy using MSC-secretions-enriched-aCSF in inflammatory/degenerative diseases of the CNS.

Immune reconstitution therapy (IRT) in multiple sclerosis: the rationale.

Immunotherapy of multiple sclerosis (MS) and other neuroimmune diseases is rapidly evolving. For the past 25 years, there has been an accelerating inclusion of new immunomodulating drugs. Based on their molecular construction and their basic mechanism of action, immunotherapeutic agents belong to the following categories: (1) cytotoxic drugs, (2) synthetic immunomodulators, (3) monoclonal antibodies, (4) vaccines (T cell vaccines, antigen vaccines), (5) oral tolerizing agents, (6) modalities that act as indirect immunosuppressants (plasmapheresis, intravenous immunoglobulins [IVIG]), and (7) cellular therapies. MS immunotherapies may also be classified in a different way, into treatments that are given continuously (chronic treatments) and medications that are applied intermittently (IRTs). The principle behind the latter is depletion of the immune system that allows it to rebuild itself. Upon its reconstitution/resetting, the immune system regains the ability to respond to infections and survey the periphery for cancer. An IRT by definition is given at short intermittent courses and not continuously. IRT modalities were shown to induce long-term remission of MS that, in some cases, is close to the definition of a "cure." There are cohorts of patients having been treated with the IRTs, alemtuzumab, and HSCT, who experience-under these modalities-no evidence of disease activity (NEDA) for over 10 years. Most importantly, IRTs cause radical changes in the lymphocyte repertoire after the reconstitution phase that may explain the long-term beneficial effects of IRT and the possibility of re-induction of self-tolerance to self/myelin antigens. In comparison, a chronic treatment cannot result in cure of the autoimmune reactivity, because it only blocks the immune system, as long as it is given; it cannot therefore radically affect the immunopathogenesis of the disease. The risks of adverse events related to immune suppression (such as opportunistic infections and secondary malignancies) with IRTs are lower and front-loaded, whereas the common side effects of chronic immunomodulation are higher and accumulate with time. In conclusion, IRT provides a novel concept for MS therapy with substantial advantages over chronic immunosuppression. IRT therapies have shown a significantly higher level of efficacy in MS. The "Holy grail" of the treatment of autoimmunity, which is to re-induce the disrupted self-tolerance, seems to be achievable-at least in part-with this approach. Moreover, the benefits of IRT, administered in short pulses, include significantly higher adherence to treatment and lower risks for accumulative side effects that are typically associated with chronic immunosuppression.

Development of a Novel Backbone Cyclic Peptide Inhibitor of the Innate Immune TLR/IL1R Signaling Protein MyD88.

MyD88 is a cytoplasmic adaptor protein that plays a central role in signaling downstream of the TLRs and the IL1R superfamily. We previously demonstrated that MyD88 plays a critical role in EAE, the murine model of multiple sclerosis, and showed that the MyD88 BB-loop decoy peptide RDVLPGT ameliorates EAE. We now designed and screened a library of backbone cyclized peptides based on the linear BB loop peptide, to identify a metabolically stable inhibitor of MyD88 that retains the binding properties of the linear peptide. We identified a novel cyclic peptide protein mimetic that inhibits inflammatory responses to TLR ligands, and NFκB activation in response to IL-1 activation. The inhibitor, c(MyD 4-4), is metabolically stable in comparison to the linear peptide, blocks MyD88 in a specific manner, and inhibits MyD88 function by preventing MyD88 dimerization. Finally, treatment of mice with c(MyD 4-4) reduced the severity of clinical disease in the murine EAE model of multiple sclerosis. Thus, modulation of MyD88-dependent signaling using c(MyD 4-4) is a potential therapeutic strategy to lower innate immune inflammation in autoimmune CNS disease.