Primary-progressive multiple sclerosis

Monoclonal antibodies and recombinant immunoglobulins for the treatment of multiple sclerosis

Multiple sclerosis (MS) is an inflammatory and degenerative disease leading to demyelination and axonal damage in the CNS. Autoimmunity plays a central role in MS pathogenesis. Per definition, monoclonal antibodies are recombinant biological compounds with a well defined target, thus carrying the promise of targeting pathogenic cells or molecules with high specificity, avoiding undesired off-target effects. Natalizumab was the first monoclonal antibody to be approved for the treatment of MS. Several other monoclonal antibodies are in development and have demonstrated promising efficacy in phase II studies. They can be categorized according to their mode of action into compounds targeting (i) leukocyte migration into the CNS (natalizumab); (ii) cytolytic antibodies (rituximab, ocrelizumab, ofatumumab, alemtuzumab); or (iii) antibodies and recombinant proteins targeting cytokines and chemokines and their receptors (daclizumab, ustekinumab, atacicept, tabalumab [Ly-2127399], secukinumab [AIN457]). In this review, we discuss the specific molecular targets, clinical efficacy and safety of these compounds and discuss criteria to anticipate the position of monoclonal antibodies in the diversifying armamentarium of MS therapy in the coming years.

Myelin water imaging reflects clinical variability in multiple sclerosis

Whilst MRI is routinely used for the assessment and diagnosis of multiple sclerosis, there is poor correspondence between clinical disability in primary progressive multiple sclerosis (PPMS) patients and conventional MRI markers of disease activity (e.g., number of enhancing lesions). As PPMS patients show diffuse and global myelin loss, the aim of this study was to evaluate the efficacy of whole-brain myelin water fraction (MWF) imaging in PPMS. Specifically, we sought to use full-brain analysis techniques to: 1) determine the reproducibility of MWF estimates in PPMS brain; 2) compare MWF values in PPMS brain to healthy controls; and 3) establish the relationship between MWF and clinical disability, regionally and globally throughout the brain. Seventeen PPMS patients and seventeen age-matched controls were imaged using a whole-brain multi-component relaxation imaging technique to measure MWF. Analysis of MWF reduction was performed on three spatial levels: 1) histogram; 2) white matter skeleton; and 3) voxel-wise at the single-subject level. From histogram analysis, PPMS patients had significantly reduced global normal appearing white matter MWF (6%, p=0.04) compared to controls. Focal lesions showed lower MWF values than white matter in controls (61%, p<0.001) and patients (59%, p<0.001). Along the white matter skeleton, MWF was diffusely reduced throughout the PPMS brain, with significant correlations between reduced MWF and increased clinical disability (more severe symptoms), as measured by the Expanded Disability Status Scale, within the corpus callosum and frontal, temporal, parietal and occipital white matter. Correlations with the more specific mental and sensory functional system scores were localized to clinically eloquent locations: reduced MWF was significantly associated with increased mental scores in anterior regions (i.e., frontal lobes and genu of the corpus callosum), and increased sensory scores in more posterior regions closer to the sensory cortex. Individual patient MWF maps were also compared to a normative population atlas, which highlighted areas of statistical difference between the individual patient and the population mean. A significant correlation was found between the volume of significantly reduced MWF and clinical disability (p=0.008, R=0.58). Our results show that clinical disability is reflected in particular regions of cerebral white matter that are consistent between subjects, and illustrates a method to examine tissue alteration throughout the brain of individual patients. These results strongly support the use of MWF imaging to evaluate disease activity in PPMS.

Genetic association of multiple sclerosis with the marker rs391745 near the endogenous retroviral locus HERV-Fc1: analysis of disease subtypes

We have previously described the occurrence of multiple sclerosis (MS) to be associated with human endogenous retroviruses, specifically the X-linked viral locus HERV-Fc1. The aim of this study was to investigate a possible association of the HERV-Fc1 locus with subtypes of MS. MS patients are generally subdivided into three categories: Remitting/Relapsing and Secondary Progressive, which together constitute Bout Onset MS, and Primary Progressive. In this study of 1181 MS patients and 1886 controls we found that Bout Onset MS was associated with the C-allele of the marker rs391745 near the HERV-Fc1 locus (p = 0.003), while primary progressive disease was not. The ability to see genetic differences between subtypes of MS near this gene speaks for the involvement of the virus HERV-Fc1 locus in modifying the disease course of MS.

Targeting VIP and PACAP receptor signalling: new therapeutic strategies in multiple sclerosis

MS (multiple sclerosis) is a chronic autoimmune and neurodegenerative pathology of the CNS (central nervous system) affecting approx. 2.5 million people worldwide. Current and emerging DMDs (disease-modifying drugs) predominantly target the immune system. These therapeutic agents slow progression and reduce severity at early stages of MS, but show little activity on the neurodegenerative component of the disease. As the latter determines permanent disability, there is a critical need to pursue alternative modalities. VIP (vasoactive intestinal peptide) and PACAP (pituitary adenylate cyclase-activating peptide) have potent anti-inflammatory and neuroprotective actions, and have shown significant activity in animal inflammatory disease models including the EAE (experimental autoimmune encephalomyelitis) MS model. Thus, their receptors have become candidate targets for inflammatory diseases. Here, we will discuss the immunomodulatory and neuroprotective actions of VIP and PACAP and their signalling pathways, and then extensively review the structure–activity relationship data and biophysical interaction studies of these peptides with their cognate receptors.

MR imaging of multiple sclerosis

Owing to its ability to depict the pathologic features of multiple sclerosis (MS) in exquisite detail, conventional magnetic resonance (MR) imaging has become an established tool in the diagnosis of this disease and in monitoring its evolution. MR imaging has been formally included in the diagnostic work-up of patients who present with a clinically isolated syndrome suggestive of MS, and ad hoc diagnostic criteria have been proposed and are updated on a regular basis. In patients with established MS and in those participating in treatment trials, examinations performed with conventional MR pulse sequences provide objective measures to monitor disease activity and progression; however, they have a limited prognostic role. This has driven the application of newer MR imaging technologies, including higher-field-strength MR units, to estimate overall MS burden and mechanisms of recovery in patients at different stages of the disease. These techniques have allowed in vivo assessment of the heterogeneity of MS pathologic features in focal lesions and in normal-appearing tissues. More recently, some of the finer details of MS, including macrophage infiltration and abnormal iron deposition, have become quantifiable with MR imaging. The utility of these modern MR techniques in clinical trial monitoring and in the assessment of the individual patient's response to treatment still need to be evaluated.

The role of advanced magnetic resonance imaging techniques in primary progressive MS

Primary progressive multiple sclerosis (PPMS) is characterized by a steady progression of irreversible disability from the onset of the disease. Although magnetic resonance imaging (MRI) is a valuable tool to quantify the disease burden in the brain and spinal cord of patients with MS, measures derived from conventional MRI, including T2-visible lesions, gadolinium-enhancing lesions and atrophy, are correlated only weakly with the clinical manifestations of PPMS. On the contrary, advanced MRI techniques are contributing significantly to the understanding of the mechanisms underlying the irreversible accumulation of disability in PPMS patients. Data from quantitative MRI studies suggest that the extent and topography of "diffuse" damage in different central nervous system (CNS) compartments (i.e. normal-appearing brain white matter and grey matter and the spinal cord) is associated with the severity of disability in PPMS and can predict subsequent medium-term disease evolution. Functional MRI studies have shown that the impairment of the adaptive capacity of the cortex to limit the clinical consequences of structural CNS damage is yet another factor contributing to the manifestations of this condition.

Different cognitive profiles of Brazilian patients with relapsing-remitting and primary progressive multiple sclerosis

Cognitive impairment is a symptom of multiple sclerosis (MS). Different clinical forms of multiple sclerosis have different cognitive profiles, according to findings of previous studies which used extensive batteries of neuropsychological tests. OBJECTIVE: To investigate cognitive profiles of Brazilian patients with relapsing-remitting multiple sclerosis (RRMS) and primary progressive multiple sclerosis (PPMS) by using a brief battery of neuropsychological tests. METHOD: Sixty-six patients, within 18-65 of age and 3-18 years of education, were paired with healthy control subjects, regarding gender, age, and education level. RESULTS: On Symbol Digit Modalities Test and Hooper Visual Organization Test, cognition was affected in 50% in RRMS and 69% in PPMS. Fluency of "F" was impaired in 24% of RRMS and 81% of PPMS. Immediate recall was affected in 32% of RRMS and in 63% of PPMS; whereas late recall, in 46% of relapsing-remitting and in 69% of primary progressive. CONCLUSION: Cognitive profiles of relapsing-remitting and primary progressive patients are different

Grey matter damage and overall cognitive impairment in primary progressive multiple sclerosis

Objectives: To identify associations between cognitive impairment and imaging measures in a cross-sectional study of patients with primary progressive multiple sclerosis (PPMS).

Methods: Neuropsychological tests were administered to 27 patients with PPMS and 31 controls. Patients underwent brain conventional magnetic resonance imaging (MRI) sequences, volumetric scans and magnetization transfer (MT) imaging; MT ratio (MTR) parameters, grey matter (GM) and normal-appearing white matter (NAWM) volumes, and WM T2 lesion load (T2LL) were obtained. In patients, multiple linear regression models identified the imaging measure associated with the abnormal cognitive tests independently from the other imaging variables. Partial correlation coefficients (PCC) were reported.

Results: Patients performed worse on tests of attention/speed of visual information processing, delayed verbal memory, and executive function, and had a worse overall cognitive performance index, when compared with controls. In patients, a lower GM peak location MTR was associated with worse overall cognitive performance ( p < 0.001, PCC = 0.77). GM mean and peak height MTR showed the strongest association with the estimated verbal intelligence quotient (IQ) decline ( p < 0.001, PCC = -0.62), and executive function ( p < 0.001, PCC = 0.79). NAWM volume was associated with attention/speed of visual information processing ( p < 0.001, PCC = 0.74), while T2LL was associated with delayed verbal memory ( p = 0.007, PCC = -0.55).

Conclusions: The finding of strong associations between GM MTR, NAWM volume and T2LL and specific cognitive impairments suggests that models that predict cognitive impairment in PPMS should include comprehensive MRI assessments of both GM and WM. However, GM MTR appears to be the main correlate of overall cognitive dysfunction, underlining the role of abnormal GM integrity in determining cognitive impairment in PPMS.

Recent Advances on the Possible Neuroprotective Activities of Epstein-Barr Virus Oncogene BARF1 Protein in Chronic Inflammatory Disorders of Central Nervous System

Multiple sclerosis and neurodegenerative diseases in which cells of the central nervous system (CNS) are lost or damaged are rapidly increasing in frequency, and there is neither effective treatment nor cure to impede or arrest their destructive course. The Epstein-Barr virus is a human gamma-herpesvirus that infects more than 90% of the human population worldwide and persisting for the lifetime of the host. It is associated with numerous epithelial cancers, principally undifferentiated nasopharyngeal carcinoma and gastric carcinoma. Individuals with a history of symptomatic primary EBV infection, called infectious mononucleosis, carry a moderately higher risk of developing multiple sclerosis (MS). It is not known how EBV infection potentially promotes autoimmunity and central nervous system (CNS) tissue damage in MS. Recently it has been found that EBV isolates from different geographic regions have highly conserved BARF1 epitopes. BARF1 protein has the neuroprotective and mitogenic activity, thus may be useful to combat and overcome neurodegenerative disease. BARF1 protein therapy can potentially be used to enhance the neuroprotective activities by combinational treatment with anti-inflammatory antagonists and neuroprotectors in neural disorders.

Chronic progressive multiple sclerosis - pathogenesis of neurodegeneration and therapeutic strategies

Multiple sclerosis (MS) is an inflammatory, autoimmune, demyelinating disease of the central nervous system (CNS) that usually starts as a relapsing-remitting disease. In most patients the disease evolves into a chronic progressive phase characterized by continuous accumulation of neurological deficits. While treatment of relapsing-remitting MS (RRMS) has improved dramatically over the last decade, the therapeutic options for chronic progressive MS, both primary and secondary, are still limited. In order to find new pharmacological targets for the treatment of chronic progressive MS, the mechanisms of the underlying neurodegenerative process that becomes apparent as the disease progresses need to be elucidated. New animal models with prominent and widespread progressive degenerative components of MS have to be established to study both inflammatory and non-inflammatory mechanisms of neurodegeneration. Here, we discuss disease mechanisms and treatment strategies for chronic progressive MS.

Treatment of walking impairment in multiple sclerosis: an unmet need for a disease-specific disability

INTRODUCTION

Walking impairment is a clinical hallmark of multiple sclerosis (MS), a chronic neurologic disease characterized by axonal demyelination and dysfunction that results in progressive disability. Until recently, there were no therapies that specifically targeted the axonal dysfunction associated with walking impairment in MS.

AREAS COVERED

The purpose of this review is to discuss the unmet need for the treatment of walking impairment in MS patients and to evaluate how a new class of pharmacologic therapies, neurofunctional modifiers, potentially addresses this unmet need. Discussion is based on clinical experience and opinions supported by publications identified in the PubMed literature using the search terms 'multiple sclerosis' and 'mobility OR walking'.

EXPERT OPINION

The development and approval of new treatments for MS show promise for improving adherence to therapy and increasing the potential for clinical effectiveness. Renewed emphasis on integrating strategies that target the underlying pathophysiology with those that address symptoms of concern to patients also has the potential to improve the lives of MS patients and their caregivers. The introduction of neurofunctional modifiers, such as dalfampridine for the improvement of walking impairment, may be of benefit by improving function, mobility and overall quality of life for MS patients.

Thalamic damage predicts the evolution of primary-progressive multiple sclerosis at 5 years

BACKGROUND AND PURPOSE

Reliable markers to monitor PPMS are still needed. We investigated whether conventional and DTI measures of thalamic damage are predictive of long-term disability accumulation in PPMS.

MATERIALS AND METHODS

Brain conventional and DTI scans were obtained at baseline and after a mean follow-up of 15 months in 54 patients with PPMS and 8 healthy controls. Patients were reassessed clinically after 5 years. At baseline and follow-up, measures of lesion load, brain atrophy, and NTV were obtained. MD and FA histograms of the NAWM, the whole GM without the thalami, and the thalami were obtained. A multivariate analysis evaluated the predictors of long-term neurologic deterioration.

RESULTS

At follow-up, 35 patients showed disability worsening. At baseline, compared with healthy controls, patients with PPMS had lower NTV (P < .001) and thalamic FA (P = .002) and higher thalamic (P = .002) and whole GM without the thalami (P = .005) MD. During follow-up, the change of thalamic FA was higher in PPMS versus healthy controls (P = .01). Baseline NTV and thalamic DTI quantities differed significantly between patients with PPMS with and without thalamic lesions. Baseline thalamic quantities were significantly correlated with the extent of brain T2 lesions and the severity of NAWM damage. The multivariate model included average NAWM MD (OR = 1.46, P = .005) and FA thalamic change (OR = 0.84, P = .02) as independent predictors of EDSS score deterioration (Nagelkerke R(2) = 0.55).

CONCLUSIONS

Short-term accrual of thalamic damage and the severity of NAWM involvement predict the long-term accumulation of disability in PPMS.

Multiple sclerosis: autoimmune disease or autoimmune reaction?

Multiple sclerosis (MS) is traditionally considered an autoimmune inflammatory demyelinating disease of the central nervous system (CNS) with much knowledge available to support this view. However, this characterization implies that the primary event is an aberrant immune response directed at CNS antigens, promoting inflammation and later driving progressive axo-glial degeneration. Trials with potent anti-inflammatory agents and detailed neuropathological studies raise questions about this sequence of events. This hypothetical paper argues that MS may be primarily a "cytodegenerative" disease, possibly first involving the oligodendrocyte/myelin unit. Liberation of autoantigens secondarily recruits an immune response, the force of which heavily depends on the host's immune predisposition. Thus, the spectrum of MS from highly aggressive Marburg type, to primary progressive disease with little inflammatory burden, is governed by a "convolution" between the underlying cytodegeneration and the host's immune predilection. Clinical heterogeneity may be a reflection of a variable immune response, whereas in reality, the "real MS" may be a homogeneous degenerative process analogous to well known primary neurodegenerative diseases.

Pharmacokinetic evaluation of idebenone

IMPORTANCE OF THE FIELD

Idebenone is a synthetic short chain benzoquinone that acts as an electron carrier in the mitochondrial electron transport chain, thereby, facilitating the production of ATP. In addition, idebenone is an antioxidant and can inhibit lipid peroxidation and may protect cell membranes and mitochondria from oxidative damage. High dose idebenone (Catena(®)) is approved in Canada for the symptomatic treatment of Friedreich's ataxia and is currently under clinical investigation for use in a number of mitochondrial and neuromuscular diseases.

AREAS COVERED IN THIS REVIEW

This review summarizes the pharmacology, pharmacokinetic and clinical efficacy/safety data of idebenone and its metabolites and provides an update of the clinical trials completed and in progress.

WHAT THE READER WILL GAIN

Following oral administration, idebenone is rapidly metabolized via oxidative shortening by a number CYP isoenzymes (CYP1A2, CYP2C9, CYP2C19, CYP2D6 and CYP3A4) to yield QS10, QS8, QS6 and QS4. Idebenone and these metabolites concomitantly undergo conjugation via glucuronidation and sulfatation to yield conjugated moieties represented as idebenone-C, QS10-C, QS8-C, QS6-C and QS4-C. Previous reports in the literature were only able to quantify plasma concentrations of idebenone measured together with its conjugates. More recently, highly sensitive and specific liquid chromatography method with tandem mass spectrometric methods have been developed, allowing the quantification of the parent molecule idebenone and its main metabolite QS10, separately.

TAKE HOME MESSAGE

After absorption, idebenone is rapidly metabolized by first pass metabolism and shows dose-proportional pharmacokinetics in healthy subjects in daily doses up to 2250 mg. The recent development of advanced analytical techniques allows the detection of idebenone and unconjugated metabolites in plasma and consequently opens the possibility for evaluation of pharmacokinetic/pharmacodynamic relationships which will be helpful to further understand the metabolism and therapeutic potential of idebenone. In clinical studies, idebenone was safe and well tolerated at doses up to 2250 mg/day.

Multiple Sklerose

Die multiple Sklerose (MS) ist eine der häufigsten neurologischen Erkrankungen, für deren Ursache es bislang keine einheitliche Erklärung gibt. Grundpfeiler der Diagnostik ist die Klinik, ergänzt durch die Magnetresonanztomographie (MRT). Eine Liquoruntersuchung zum Nachweis der entzündlichen Genese nachgewiesener multifokaler Störungen ist bei allen unklaren Fällen und bei älteren Patienten erforderlich. Zur Bestätigung und Verlaufskontrolle sind elektrophysiologische Verfahren hilfreich.

FTY720 (fingolimod) efficacy in an animal model of multiple sclerosis requires astrocyte sphingosine 1-phosphate receptor 1 (S1P1) modulation

Sphingosine 1-phosphate (S1P), a lysophospholipid, has gained relevance to multiple sclerosis through the discovery of FTY720 (fingolimod), recently approved as an oral treatment for relapsing forms of multiple sclerosis. Its mechanism of action is thought to be immunological through an active phosphorylated metabolite, FTY720-P, that resembles S1P and alters lymphocyte trafficking through receptor subtype S1P(1). However, previously reported expression and in vitro studies of S1P receptors suggested that direct CNS effects of FTY720 might theoretically occur through receptor modulation on neurons and glia. To identify CNS cells functionally contributing to FTY720 activity, genetic approaches were combined with cellular and molecular analyses. These studies relied on the functional assessment, based on clinical score, of conditional null mouse mutants lacking S1P(1) in CNS cell lineages and challenged by experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis. All conditional null mutants displayed WT lymphocyte trafficking that responded normally to FTY720. In marked contrast, EAE was attenuated and FTY720 efficacy was lost in CNS mutants lacking S1P(1) on GFAP-expressing astrocytes but not on neurons. In situ hybridization studies confirmed that astrocyte loss of S1P(1) was the key alteration in functionally affected mutants. Reductions in EAE clinical scores were paralleled by reductions in demyelination, axonal loss, and astrogliosis. Receptor rescue and pharmacological experiments supported the loss of S1P(1) on astrocytes through functional antagonism by FTY720-P as a primary FTY720 mechanism. These data identify nonimmunological CNS mechanisms of FTY720 efficacy and implicate S1P signaling pathways within the CNS as targets for multiple sclerosis therapies.

The role of infections in the pathogenesis and course of multiple sclerosis

Interplay between susceptibility genes and environmental factors is considered important player in the genesis of multiple sclerosis (MS). Among environmental factors, a role for an infectious pathogen has long been considered central to the disease process. This opinion has support both from epidemiological data and the findings of immunological abnormalities in spinal fluid that reflect an immune response to an as yet undetermined antigen, possibly a pathogen, in the cerebrospinal fluid. Our review will outline the current understanding of the role of infection in the causation and progression of MS. We will review the data that point to an infectious cause of MS and consider the specific agents Chlamydophila (Chlamydia) pneumoniae, Human Herpes Virus 6, and Epstein-Barr Virus, that are implicated in either the development or progression of MS.

New approaches in the management of multiple sclerosis

Multiple sclerosis (MS) is a central nervous system chronic inflammatory disease that is characterized by an extensive and complex immune response. Scientific advances have occurred in immunology, pathophysiology, and diagnostic and clinical assessment tools, and recent discovery of unique therapeutic targets has spurred numerous Phase II and Phase III clinical trials. Reductions in MS relapse rates and improvements in T₂ or gadolinium-enhancing lesion burdens have been reported from Phase III trials that include fingolimod, alemtuzumab, cladribine, and rituximab. Promising Phase II trial data exist for teriflunomide, daclizumab, laquinimod, and fumarate. The optimism created by these favorable findings must be tempered with evaluation of the adverse effect profile produced by these new agents. Given the discovery of progressive multifocal leukoencephalopathy with the use of natalizumab, ongoing vigilance for rare and life-threatening reactions due to new agents should be paramount. Patients with MS often experience difficulty with ambulation, spasticity, and cognition. Recent clinical trial data from two Phase III dalfampridine-SR trials indicate certain patients receive benefits in ambulation. This article provides an overview of data from clinical trials of newer agents of potential benefit in MS.

Primary progressive versus relapsing-onset multiple sclerosis: presence and prognostic value of cerebrospinal fluid oligoclonal IgM

BACKGROUND

There is increasing evidence on cerebrospinal fluid (CSF) oligoclonal IgM (OCIgM) predicting a more aggressive disease course in relapsing-remitting Multiple Sclerosis (MS), while there is a scarcity of data for primary progressive MS (PPMS).

OBJECTIVE

Our aim was to investigate the presence and possible prognostic value of CSF OCIgM in a group of PPMS and in a group of relapsing-onset MS patients. The possible prognostic role of other clinical and biological factors was also evaluated.

METHODS

We calculated the impact of single clinical and biological factors, including CSF OCIgM at onset, on the probability of reaching an Expanded Disability Status Scale of 3 and 4 in 45 PPMS and 104 relapsing-onset MS patients.

RESULTS

CSF OCIgM were found in only 13% of PPMS patients and did not influence the time taken to reach an Expanded Disability Status Scale of 3 and 4. Conversely, they were present in 46% of relapsing-onset MS patients and increased the risk of reaching an Expanded Disability Status Scale of 4. Clinical factors with a negative prognostic value in PPMS were age at onset <30 years and onset with pyramidal symptoms, while onset with sensory symptoms in relapsing-onset MS predicted a more favourable course.

CONCLUSION

This study confirms that, in relapsing-onset MS patients, the presence of CSF OCIgM at onset predicts a worse disease course. In the cohort of PPMS patients, however, CSF OCIgM were rare, suggesting that heterogeneous pathogenetic mechanisms may be involved in the different MS forms.

Patient-orientated longitudinal study of multiple sclerosis in south west England (The South West Impact of Multiple Sclerosis Project, SWIMS) 1: protocol and baseline characteristics of cohort

Background

There is a need for greater understanding of the impact of multiple sclerosis (MS) from the perspective of individuals with the condition. The South West Impact of MS Project (SWIMS) has been designed to improve understanding of disease impact using a patient-centred approach. The purpose is to (1) develop improved measurement instruments for clinical trials, (2) evaluate longitudinal performance of a variety of patient-reported outcome measures, (3) develop prognostic predictors for use in individualising drug treatment for patients, particularly early on in the disease course.

Methods

This is a patient-centred, prospective, longitudinal study of multiple sclerosis and clinically isolated syndrome (CIS) in south west England. The study area comprises two counties with a population of approximately 1.7 million and an estimated 1,800 cases of MS. Self-completion questionnaires are administered to participants every six months (for people with MS) or 12 months (CIS). Here we present descriptive statistics of the baseline data provided by 967 participants with MS.

Results

Seventy-five percent of those approached consented to participate. The male:female ratio was 1.00:3.01 (n = 967). Average (standard deviation) age at time of entry to SWIMS was 51.6 (11.5) years (n = 961) and median (interquartile range) time since first symptom was 13.3 (6.8 to 24.5) years (n = 934). Fatigue was the most commonly reported symptom, with 80% of participants experiencing fatigue at baseline. Although medication use for symptom control was common, there was little evidence of effectiveness, particularly for fatigue. Nineteen percent of participants were unable to classify their subtype of MS. When patient-reported subtype was compared to neurologist assessment for a sample of participants (n = 396), agreement in disease sub-type was achieved in 63% of cases. There were 836 relapses, reported by 931 participants, in the twelve months prior to baseline. Twenty-three percent of the relapsing-remitting group and 12% of the total sample were receiving disease-modifying therapy at baseline.

Conclusions

Demographics of this sample were similar to published data for the UK. Overall, the results broadly reflect clinical experience in confirming high symptom prevalence, with relatively little complete symptom relief. Participants often had difficulty in defining MS relapses and their own MS type.

Compliance with McDonald criteria and red flag recognition in a general neurology practice in Ireland

BACKGROUND

The revised McDonald criteria aim to simplify and speed the diagnosis of multiple sclerosis (MS). An important principle of the criteria holds there should be no better explanation for the clinical presentation. In Miller et al.'s consensus statement on the differential diagnosis of MS, red flags are identified that may suggest a non-MS diagnosis.

OBJECTIVE

All new patients with a practice diagnosis of MS were assessed for compliance with McDonald criteria. The group of patients not fulfilling criteria was followed up to assess compliance over time. At the end of the follow-up period, red flags were sought in the group of patients who remained McDonald criteria negative.

METHODS

Clinical notes and paraclinical tests were examined retrospectively for compliance with McDonald criteria and for the presence of red flags.

RESULTS

Sixty-two patients were identified, with two lost to follow-up. Twenty-six (42%) patients fulfilled criteria at diagnosis. After 53 months follow-up, 47 (78%) patients fulfilled criteria. In the 13 (22%) patients who remain McDonald criteria negative, a total of 20 red flags were identified, ranging from one to six per patient. Alternative diagnoses were considered and further investigations performed in 10 patients with no significantly abnormal results.

CONCLUSION

Twenty-two percent of patients still do not fulfill McDonald criteria after 53 months. Dissemination in time was not proven in the majority of patients and the lack of follow-up neuroimaging was an important factor in this. Red flags may be useful in identifying alternative diagnoses, but the yield was low in our cohort.

Demyelination versus remyelination in progressive multiple sclerosis

The causes of incomplete remyelination in progressive multiple sclerosis are unknown, as are the pathological correlates of the different clinical characteristics of patients with primary and secondary progressive disease. We analysed brains and spinal cords from 51 patients with progressive multiple sclerosis by planimetry. Thirteen patients with primary progressive disease were compared with 34 with secondary progressive disease. In patients with secondary progressive multiple sclerosis, we found larger brain plaques, more demyelination in total and higher brain loads of active demyelination compared with patients with primary progressive disease. In addition, the brain density of plaques with high-grade inflammation and active demyelination was highest in secondary progressive multiple sclerosis and remained ~18% higher than in primary progressive multiple sclerosis after adjustments for other plaque types and plaque number (P<0.05). Conversely, the proportion of remyelinated shadow plaques (P<0.05) and the overall remyelination capacity (P<0.01) per brain were higher in primary, compared with secondary, progressive multiple sclerosis. By contrast, there were no group differences in the brain load or frequency of low-grade inflammatory plaques with slowly expanding demyelination. Spinal cord lesion loads and remyelination capacity were also comparable in the two patient groups. Remyelinated areas were more vulnerable than the normal-appearing white matter to new demyelination, including active demyelination in secondary progressive multiple sclerosis. 'Recurrent' slowly expanding demyelination, affecting remyelinated areas, and the load of slowly expanding demyelination correlated with incomplete remyelination in both groups. In turn, incomplete remyelination in the spinal cord correlated with higher disease-related disability (determined retrospectively; r = -0.53; P<0.05 for remyelination capacity versus disease severity). By contrast, such a correlation was not observed in the brain. We propose that regulatory and reparative properties could protect the white matter of the brain in patients with primary progressive multiple sclerosis. These patients may, thereby, be spared symptoms until the spinal cord is affected. By contrast, recurrent active demyelination of repaired myelin could explain why similar symptoms often develop in consecutive relapses in relapsing-remitting/secondary progressive multiple sclerosis. Our data also indicate that slowly expanding demyelination may irreparably destroy normal and repaired myelin, supporting the concept of slowly expanding demyelination as an important pathological correlate of clinical progression.

Proteomics comparison of cerebrospinal fluid of relapsing remitting and primary progressive multiple sclerosis

Background

Based on clinical representation of disease symptoms multiple sclerosis (MScl) patients can be divided into two major subtypes; relapsing remitting (RR) MScl (85–90%) and primary progressive (PP) MScl (10–15%). Proteomics analysis of cerebrospinal fluid (CSF) has detected a number of proteins that were elevated in MScl patients. Here we specifically aimed to differentiate between the PP and RR subtypes of MScl by comparing CSF proteins.

Methodology/Principal Findings

CSF samples (n = 31) were handled according to the same protocol for quantitative mass spectrometry measurements we reported previously. In the comparison of PP MScl versus RR MScl we observed a number of differentially abundant proteins, such as protein jagged-1 and vitamin D-binding protein. Protein jagged-1 was over three times less abundant in PP MScl compared to RR MScl. Vitamin D-binding protein was only detected in the RR MScl samples. These two proteins were validated by independent techniques (western blot and ELISA) as differentially abundant in the comparison between both MScl types.

Conclusions/Significance

The main finding of this comparative study is the observation that the proteome profiles of CSF in PP and RR MScl patients overlap to a large extent. Still, a number of differences could be observed. Protein jagged-1 is a ligand for multiple Notch receptors and involved in the mediation of Notch signaling. It is suggested in literature that the Notch pathway is involved in the remyelination of MScl lesions. Aberration of normal homeostasis of Vitamin D, of which approximately 90% is bound to vitamin D-binding protein, has been widely implicated in MScl for some years now. Vitamin D directly and indirectly regulates the differentiation, activation of CD4+ T-lymphocytes and can prevent the development of autoimmune processes, and so it may be involved in neuroprotective elements in MScl.

Functional MR imaging correlates of neuropsychological impairment in primary-progressive multiple sclerosis

BACKGROUND AND PURPOSE

Cognitive deficits affect

MATERIALS AND METHODS

From 16 right-handed patients with PPMS and 17 matched controls, structural and fMRIs (during the performance of the 2-back task) were acquired. Neuropsychological tests exploring memory, attention, and frontal lobe cognitive domains were administered. T2 LL, NBV, and CC areas were measured.

RESULTS

Six patients with PPMS were CI. Structural MR imaging measures did not differ between patients who were CI and those who were CP. Compared with patients who were CI, patients who were CP had increased activations of the left caudate nucleus, PFC, and inferior parietal lobule. Compared with controls and patients who were CP, patients who were CI had increased activations of the SII, cerebellum, and insula. Compared with controls, they also had increased activations of the right precentral gyrus and a reduced recruitment of the left PFC. In patients with PPMS, a decreased composite cognitive score correlated with increased activity of the cerebellum, insula, and SII, as well as decreased PFC activity. T2 LL correlated with decreased PFC recruitment and increased SII recruitment.

CONCLUSIONS

In PPMS, an increased recruitment of cognitive-related networks might represent a functional reserve with the potential to limit the severity of cognitive impairment. The accumulation of T2 lesions and the consequent exhaustion of frontal lobe plasticity might contribute to cognitive impairment in PPMS.

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MESH Headings

• Adult
• Aged
• Brain/physiopathology
• Cerebellum/physiopathology
• Cognition Disorders/diagnosis
• Cognition Disorders/etiology
• Cognition Disorders/physiopathology
• Female
• Frontal Lobe/physiopathology
• Humans
• Magnetic Resonance Imaging
• Male
• Middle Aged
• Multiple Sclerosis, Chronic Progressive/complications
• Multiple Sclerosis, Chronic Progressive/diagnosis
• Multiple Sclerosis, Chronic Progressive/physiopathology
• Neuronal Plasticity/physiology
• Neuropsychological Tests
• Parietal Lobe/physiopathology
• Severity of Illness Index

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Affiliation(s)

M A Rocca Neuroimaging Research Unit, Institute of Experimental Neurology, Scientific Institute and University Ospedale San Raffaele, Milan, Italy
G Riccitelli
M Rodegher
A Ceccarelli
A Falini
M Falautano
A Meani
G Comi
Massimo Filippi

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Mechanism of action of oral fingolimod (FTY720) in multiple sclerosis

Fingolimod (FTY720) is a first-in-class orally bioavailable compound that has shown efficacy in advanced clinical trials for the treatment of multiple sclerosis (MS). In vivo, fingolimod is phosphorylated to form fingolimod-phosphate, which resembles naturally occurring sphingosine 1-phosphate (S1P), an extracellular lipid mediator whose major effects are mediated by cognate G protein-coupled receptors. There are at least 5 S1P receptor subtypes, known as S1P subtypes 1-5 (S1P1-5), 4 of which bind fingolimod-phosphate. These receptors are expressed on a wide range of cells that are involved in many biological processes relevant to MS. S1P1 plays a key role in the immune system, regulating lymphocyte egress from lymphoid tissues into the circulation. Fingolimod-phosphate initially activates lymphocyte S1P1 via high-affinity receptor binding yet subsequently induces S1P1 down-regulation that prevents lymphocyte egress from lymphoid tissues, thereby reducing autoaggressive lymphocyte infiltration into the central nervous system (CNS). S1P receptors are also expressed by many CNS cell types and have been shown to influence cell proliferation, morphology, and migration. Fingolimod crosses the blood-brain barrier and may therefore have direct CNS effects, distinguishing it from immunologically targeted MS therapies. Prophylactic administration of fingolimod to animals with experimental autoimmune encephalitis (EAE), a model of MS, completely prevents development of EAE features, whereas therapeutic administration significantly reduces clinical severity of EAE. Therapeutic efficacy observed in animal studies has been substantiated in phase 2 and 3 trials involving patients with relapsing or relapsing-remitting MS.

Understanding unexpected courses of multiple sclerosis among patients using complementary and alternative medicine: A travel from recipient to explorer

Complementary and alternative medicine (CAM) is frequently used by patients with multiple sclerosis (MS). Some MS patients experience unexpected improvements of symptoms, which they relate to their use of CAM. The aim of this study was to obtain knowledge and develop understandings of such self-defined unexpected improvement of MS symptoms. Two cases were constructed based on documents and 12 qualitative interviews. Our aim was not to make generalisations from the cases, but to transfer knowledge as working hypotheses. We identified four health-related change processes: the process of losing bodily competence; the process of developing responsibility; the process of taking control; and the process of choosing CAM. The patients explained unexpected improvements in their MS symptoms as results of their own efforts including their choice and use of CAM. In our theoretical interpretations, we found the patients' redefinition of history, the concept of treatment and the importance of conventional health care to be essential, and leading to a change of patients' position towards conventional health care from recipients to explorers. The explorers can be perceived as boundary walkers reflecting limitations within the conventional health care system and as initiators regarding what MS patients find useful in CAM.

Retinal nerve fiber layer thickness in subgroups of multiple sclerosis, measured by optical coherence tomography and scanning laser polarimetry

Optical coherence tomography (OCT) and scanning laser polarimetry (GDx ECC) are non-invasive methods used to assess retinal nerve fiber layer (RNFL) thickness, which may be a reliable tool used to monitor axonal loss in multiple sclerosis (MS). The objectives of this study are (1) to compare OCT with the GDx ECC; (2) to assess and compare the RNFL thickness in subgroups of MS. Ophthalmologic examination and RNFL assessment by OCT and GDx were performed in 65 MS patients (26 relapsing-remitting (RRMS), ten secondary-progressive (SPMS), 29 primary-progressive (PPMS)). Twenty-eight patients (43%) had a history of optic neuritis (ON). Adjustments were made for age and disease duration. RNFL thickness was reduced in eyes with previous ON (p < 0.01). No differences were found between PPMS and relapse-onset MS. OCT and GDx ECC measurements were moderately correlated (rho = 0.73, p < 0.01). Visual field-mean deviation (MD) values correlated with OCT means (r = 0.44, p < 0.01) and GDx ECC TSNIT average (r = 0.41, p < 0.01). In patients without previous ON, EDSS correlated with MD (r = −0.36, p < 0.01), visual field-pattern standard deviation (PSD) (r = 0.30, p < 0.05), OCT means (r = −0.31–0.30, p < 0.05) and macular volume (r = −0.37, p < 0.01). For MSIS-29 physical impact score, significant correlations were found with MD (r = −0.48, p < 0.01) and PSD (r = 0.48, p < 0.01). Conclusions: No differences between PPMS and relapse-onset MS subgroups were found. RNFL thickness was reduced in eyes with previous ON. Although OCT and GDx ECC findings were moderately correlated and showed significant correlations with measures of visual function in patients without previous ON, EDSS correlated significantly with visual and OCT measures, but not with GDx ECC.

Comparative gene expression analysis in mouse models for multiple sclerosis, Alzheimer's disease and stroke for identifying commonly regulated and disease-specific gene changes

The brain responds to injury and infection by activating innate defense and tissue repair mechanisms. Working upon the hypothesis that the brain defense response involves common genes and pathways across diverse pathologies, we analysed global gene expression in brain from mouse models representing three major central nervous system disorders, cerebral stroke, multiple sclerosis and Alzheimer's disease compared to normal brain using DNA microarray expression profiling. A comparison of dysregulated genes across disease models revealed common genes and pathways including key components of estrogen and TGF-beta signaling pathways that have been associated with neuroprotection as well as a neurodegeneration mediator, TRPM7. Further, for each disease model, we discovered collections of differentially expressed genes that provide novel insight into the individual pathology and its associated mechanisms. Our data provide a resource for exploring the complex molecular mechanisms that underlie brain neurodegeneration and a new approach for identifying generic and disease-specific targets for therapy.

Increased cerebrospinal fluid chitotriosidase index in patients with multiple sclerosis

OBJECTIVE

To investigate chitotriosidase (CTTS) activity in serum and cerebrospinal fluid (CSF) in multiple sclerosis (MS) patients in relation to disease course and CSF markers for immune activation or inflammation.

MATERIALS AND METHODS

We studied 80 patients with relapsing-remitting MS (RRMS), 24 with secondary progressive MS (SPMS), 20 with primary progressive MS (PPMS) and 29 patients with other neurological disorders (OND). We measured CTTS activity and studied the correlation with CSF mononuclear cell count (MNC) and intrathecal IgG production.

RESULTS

CTTS activity was significantly higher in CSF, but not in serum, from the total MS group compared with OND and controls. In RRMS and SPMS CTTS, index was increased compared with controls (RRMS, 0.10 +/- 0.21; SPMS, 0.10 +/- 0.15; controls, 0.021 +/- 0.020), but not in PPMS (0.061 +/- 0.052). CTTS index was higher in MS patients with elevated MNC or CSF-restricted oligoclonal IgG bands than in MS patients without these CSF findings.

CONCLUSIONS

CTTS index is elevated in RRMS and SPMS. The CTTS index is related to CSF markers of inflammation or immune activation.

Disease onset in familial and sporadic primary progressive multiple sclerosis

The pathophysiology of primary progressive (PP) multiple sclerosis (MS) involves diffuse axonal degeneration which is believed to start early in the disease process, even before the onset of clinical symptoms. Symptomatic onset then occurs when this process reaches a threshold after which the axonal loss can no longer be compensated. A preliminary study showed that patients with familial PPMS had an earlier clinical onset than patients with sporadic disease, suggesting a hereditary component to the disease process of PPMS. In this study, we combined data from two large, population-based, longitudinal MS databases to investigate disease onset in familial and sporadic PPMS. We examined 411 patients with PPMS. There were no differences in gender distribution or onset symptoms between familial and sporadic PPMS. Patients with familial PPMS were significantly younger at disease onset (n = 84, median age: 37.6 years) than patients with sporadic disease (n = 327, median age: 42.7, p = 0.007). This difference was due to a greater proportion of familial cases with a disease onset before the age of 30 and a smaller proportion with disease onset between 40 and 50 years of age (p = 0.002). Gender had no significant effect on the age at disease onset. Further analyses showed that these findings were unlikely to be due to ascertainment bias towards an earlier diagnosis in familial cases. Our findings suggest a hereditary component to the disease process of PPMS. It would be worthwhile to identify patients with familial PPMS for future research on disease modifying genes in MS.

Structural and functional magnetic resonance imaging correlates of motor network dysfunction in primary progressive multiple sclerosis

We combined functional magnetic resonance imaging (fMRI) and diffusion tensor tractography to investigate the functional and structural substrates of motor network dysfunction in patients with primary progressive multiple sclerosis (PPMS). In 15 right-handed PPMS patients and 15 age-matched healthy controls, we acquired diffusion tensor magnetic resonance imaging and fMRI during the performance of a simple motor task. Tractography was used to calculate diffusion tensor-derived measures of the corpus callosum, the corticospinal tract, the optic radiation, the fronto-occipital fasciculus, and the inferior longitudinal fasciculus. Analyses of fMRI activations and functional connectivity were performed using statistical parametric mapping (cluster threshold of P = 0.001, and extent cluster threshold of 10 voxels for comparison of activations; P < 0.05, family-wise error corrected for functional connectivity). As compared with controls, PPMS patients had more significant activations of the left postcentral gyrus, left secondary sensorimotor area, left parahippocampal gyrus, left cerebellum, right primary sensorimotor cortex (SMC), right basal ganglia, right insula, right cingulum, and cuneus bilaterally. As compared with PPMS patients, controls had increased functional connectivity between the left primary SMC and the ipsilateral inferior frontal gyrus. Conversely, PPMS patients showed increased functional connectivity between the left primary SMC and the right cuneus. Moderate correlations were found between functional activations and damage to the tracts studied (r-values between 0.82 and 0.84; P < 0.001). These results suggest that, as compared with healthy controls, PPMS patients show increased activations and abnormal functional connectivity measures in several areas of the sensorimotor network. Such changes are correlated with the structural damage to the white matter fiber bundles connecting these regions.

Characterization of relapsing-remitting and chronic forms of experimental autoimmune encephalomyelitis in C57BL/6 mice

Multiple sclerosis (MS) is an autoimmune, demyelinating disease of the central nervous system (CNS). Like MS, the animal model experimental autoimmune encephalomyelitis (EAE) is characterized by CNS inflammation and demyelination and can follow a relapsing-remitting (RR) or chronic (CH) disease course. The molecular and pathological differences that underlie these different forms of EAE are not fully understood. We have compared the differences in RR- and CH-EAE generated in the same mouse strain (C57BL/6) using the same antigen. At the peak of disease when mice in both groups have similar clinical scores, CH-EAE is associated with increased lesion burden, myelin loss, axonal damage, and chemokine/cytokine expression when compared with RR-EAE. We further showed that inflammation and myelin loss continue to worsen in later stages of CH-EAE, whereas these features are largely resolved at the equivalent stage in RR-EAE. Additionally, axonal loss at these later stages is more severe in CH-EAE than in RR-EAE. We also demonstrated that CH-EAE is associated with a greater predominance of CD8(+) T cells in the CNS that exhibit MOG(35-55) antigen specificity. These studies therefore showed that, as early as the peak stage of disease, RR- and CH-EAE differ remarkably in their immune cell profile, chemokine/cytokine responses, and histopathological features. These data also indicated that this model of CH-EAE exhibits pathological features of a chronic-progressive disease profile and suggested that the sustained chronic phenotype is due to a combination of axonal loss, myelin loss, and continuing inflammation.

Factors associated with delay to medical recognition in two Canadian multiple sclerosis cohorts

Long referral and diagnostic delays can impact both the opportunity for early therapeutic intervention and estimates of MS incidence and prevalence. We investigated factors associated with diagnostic or referral delays within two geographically distinct MS Canadian cohorts and the association between referral delay and disability at first clinic visit. Adult-onset MS patients were selected from the population-based British Columbian MS (BCMS) (n=5705) and the clinic-based Hôpital Notre-Dame, Quebec (CHUM) (n=1489) databases. Referral delay (BCMS) and diagnostic delay (CHUM) were examined by sex, onset age, disease course (primary progressive (PPMS) vs. relapsing at onset), onset symptoms (BCMS only) and year of first clinic visit/diagnosis. Cohorts were analyzed separately by stratified analyses and multivariable linear modeling. The relationship between referral delay and initial disability was examined by multiple ordinal regression in the BCMS cohort. Younger at onset patients or those with PPMS exhibited significantly longer delays (p<0.001). Delays decreased over the 20+ year period, but reductions varied by clinical course, onset age and sex. Long referral delays were associated with greater disability at first clinic visit (p<0.001). If early intervention at mild disability levels is warranted in MS, then the extended delays to medical recognition for young adult-onset and PPMS patients must be addressed.

Sexual dimorphism of oligodendrocytes is mediated by differential regulation of signaling pathways

Sexual dimorphism of white matter has not been considered important, the assumption being that sex hormones are not essential for glial development. We recently showed exogenous hormones in vivo differentially regulate in male and female rodents the life span of oligodendrocytes (Olgs) and amount of myelin (Cerghet et al. [2006] J. Neurosci. 26:1439-1447). To determine which hormones regulate male and female Olg development, we prepared enriched Olg cultures grown in serum-free medium with estrogen (E2), progesterone (P2), and dihydrotestosterone (DHT) or their combinations. P2 significantly increased the number of Olgs in both sexes, but more so in females; E2 had minor effects on Olg numbers; and DHT reduced Olgs numbers in both sexes, but more so in females. Combinations of hormones affected Olg numbers differently from single hormones. The change in Olg numbers was due to changes not in proliferation but rather in survival. P2 increased pAKT by many-fold, but MAPK levels were unchanged, indicating that activation of the Akt pathway by P2 is sufficient to regulate Olg differentiation. DHT reduced pAkt in both sexes but differentially increased pMAPK in males and decreased it in females. Stressing Olgs reveals that both sexes are protected by P2, but females are slightly better protected than males. Females always showed greater differences than males regarding changes in Olg numbers and in signaling molecules. Given the greater fluctuation of neurosteroids in women than in men and the higher incidence of multiple sclerosis (MS) in women, these sexually dimorphic differences may contribute to differences in male and female MS lesions.

Interferon Beta for primary progressive multiple sclerosis

BACKGROUND

This is an updated Cochrane review of the previous version published (Cochrane Database of Systematic Reviews 2009, Issue 1. Art. No.: CD006643. DOI: 10.1002/14651858.CD006643.pub2).Therapeutic trials with ss-interferon in Multiple Sclerosis (MS) have mainly focused on remitting-relapsing multiple sclerosis (RRMS), demonstrating a reduction in relapse rate. However, there is not enough evidence about their efficacy in patients with primary progressive multiple sclerosis (PPMS).

OBJECTIVES

Identify and summarize the evidence that ss-interferon is beneficial and safe in patients with PPMS.

SEARCH STRATEGY

We searched the Cochrane MS Group Trials Register (May 2009); The Cochrane Central Register of Controlled Trials (CENTRAL) The Cochrane Library, (2009, Issue 2); MEDLINE (PubMed) (January 1966 to May 2009), EMBASE (January 1974 to May 2009); NICE (January 1999 to May 2009); LILACS (January 1986 to May 2009); Screening of reference lists of all primary studies found; Contact and inquiry of drug manufactures and multiple sclerosis experts.

SELECTION CRITERIA

Randomized double or single blind, placebo-controlled trials of recombinant ss-interferon in patients with PPMS including trials of MS which report separate outcomes in subgroups of patients with PPMS.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted and assessed trials' quality according to the criteria outlined in The Cochrane Handbook.

MAIN RESULTS

Of 1777 potential studies evaluated, only two Randomized Control Trials (123 patients) were included. ss-interferon treatment compared to placebo did not show differences regarding the proportion of patients with progression of the disease (RR 0.89, 95% CI 0.55 to1.43), and it was associated with a greater frequency of treatment-related adverse events (RR 1.90, 95% CI 1.45-2.48). One of the trials evaluated the MRI secondary outcome pre-specified in the protocol. This trial showed that at two years the numbers of active lesions on brain MRI scan in ss-interferon arm were significantly lower than in placebo arm (weighted mean difference -1.3, 95% CI -2.15 to -0.45, P = 0.003); also, the number of participants with active lesions was significantly higher in placebo arm vs. ss-interferon arm at two years (RR 0.43, 95% CI 0.22 to 0.86, P = 0.02).

AUTHORS' CONCLUSIONS

Limited data on the effect of ss-interferon treatment on PPMS exists. Only two single-centre placebo controlled trials of interferon beta have been done. Based on this review, the included studies showed that ss-interferon treatment was not associated with reduced disability progression in PPMS patients. However, the trial population was too small to allow definitive conclusions on the efficacy of ss-interferon therapy in PPMS patients. Larger research studies need to be done in patients with PPMS in order to clarify whether ss-interferon is effective in this population.

Brain MRI findings in long-standing and disabling multiple sclerosis in 84 patients

OBJECTIVE

To look for cerebral white matter MRI changes in patients with long-standing and disabling MS.

METHODS

We analyzed retrospectively brain MRIs (performed 10 or more years after symptom onset) of patients with MS diagnosis and expanded disability status scale of 6 or more. The following parameters were analyzed: total number of brain T2 hyperintensities; number of brainstem, cerebellar, corpus callosum, basal ganglia, and juxtacortical T2 hyperintensities; diffuse leukoencephalopathy score; total number of T1 hypointensities.

RESULTS

Eighty-four patients were included. The mean time between symptom onset and MRI was 20.2 years. Eight percent had less than 9 cerebral T2 hyperintensities. Posterior fossa, juxtacortical, and corpus callosum T2 hyperintensities, and T1 hypointensities lacked in respectively 19%, 12%, 47%, and 8%. Overall, normal MRI was not seen, 6% had abnormal MRI but did not meet Barkhof's criteria, and the remaining 94% had MRI abnormalities fulfilling Barkhof's criteria. Moderate or severe diffuse leukoencephalopathy was seen in 69%. Extensive diffuse leukoencephalopathy predominant to nodular lesions was seen in 5%.

CONCLUSIONS

Despite long-standing and disabling MS, typical MRI abnormalities lacked in a minority of patients, and 6% did not fulfil Barkhof's criteria. The majority showed moderate or severe diffuse leukoencephalopathy.

Initiation and progression of axonopathy in experimental autoimmune encephalomyelitis

Axonal loss is the principal cause of chronic disability in multiple sclerosis and experimental autoimmune encephalomyelitis (EAE). In C57BL/6 mice with EAE induced by immunization with myelin oligodendrocyte glycoprotein peptide 35-55, the first evidences of axonal damage in spinal cord were in acute subpial and perivascular foci of infiltrating neutrophils and lymphocytes and included intra-axonal accumulations of the endovesicular Toll-like receptor TLR8, and the inflammasome protein NAcht leucine-rich repeat protein 1 (NALP1). Later in the course of this illness, focal inflammatory infiltrates disappeared from the spinal cord, but there was persistent activation of spinal cord innate immunity and progressive, bilaterally symmetric loss of small-diameter corticospinal tract axons. These results support the hypothesis that both contact-dependent and paracrine interactions of systemic inflammatory cells with axons and an innate immune-mediated neurodegenerative process contribute to axonal loss in this multiple sclerosis model.