The mystery of the origin of multiple sclerosis

Therapeutic Value of Single Nucleotide Polymorphisms on the Efficacy of New Therapies in Patients with Multiple Sclerosis

The introduction of new therapies for the treatment of multiple sclerosis (MS) is a very recent phenomenon and little is known of their mechanism of action. Moreover, the response is subject to interindividual variability and may be affected by genetic factors, such as polymorphisms in the genes implicated in the pathologic environment, pharmacodynamics, and metabolism of the disease or in the mechanism of action of the medications, influencing the effectiveness of these therapies. This review evaluates the impact of pharmacogenetics on the response to treatment with new therapies in patients diagnosed with MS. The results suggest that polymorphisms detected in the GSTP1, ITGA4, NQO1, AKT1, and GP6 genes, for treatment with natalizumab, ZMIZ1, for fingolimod and dimethyl fumarate, ADA, for cladribine, and NOX3, for dimethyl fumarate, may be used in the future as predictive markers of treatment response to new therapies in MS patients. However, there are few existing studies and their samples are small, making it difficult to generalize the role of these genes in treatment with new therapies. Studies with larger sample sizes and longer follow-up are therefore needed to confirm the results of these studies.

Multiple sclerosis - the remarkable story of a baffling disease

Multiple sclerosis has always been an enigma to its sufferers, their families, medical investigators, and clinicians. For many centuries, there have been attempts to understand its causes and nature, and to discover treatment methods. In the Middle Ages, the disease was claimed to be sent directly from God. A significant development in exploring multiple sclerosis took place in the 19th century, when Jean-Martin Charcot and his colleagues distinguished the disease, precisely described its symptoms, attempted to explain its pathophysiology, and introduced the first methods of symptomatic treatment. The 20th century was a period of discovery and development of diagnostic techniques, such as cerebrospinal fluid analysis, evoked potentials, and magnetic resonance imaging as well as an era of introducing steroid therapy for acute treatment. Currently, the dynamic development of disease modifying therapy and neuroimaging can be observed. The paper aims to delve into the remarkable history of multiple sclerosis by focusing on the earliest case reports and discovery of the disease and exploring its nature, diagnostic methods, and treatment.

Effectiveness of Amantadine in Reducing Relapses in Multiple Sclerosis

Fifty-three patients with multiple sclerosis were assessed in a double-blind multicentre study for the effect of amantadine. The patients were observed in general practices for up to four years. Relapses occurred in 5 of the 24 patients treated with amantadine and in 14 of the 29 placebo-treated patients. Neurological deterioration was not significantly different in the two groups.

The cause of multiple sclerosis is autoimmune attack of adenosyltransferase thereby limiting adenosylcobalamin production

The pathogenesis of multiple sclerosis (MS) begins with an infection by a bacterium from the class of bacteria that produce and utilize adenosylcobalamin (AdoCbl) and possess an adenosyl transferase enzyme (ATR); these bacteria are the exogenous antigens that cause MS. Human ATR is homologous to bacterial ATR and B cells produce anti-ATR antibodies as an autoimmune response thereby reducing the concentration of ATR and thus limiting production of AdoCbl, one of the two bioactive forms of vitamin B12. The next step in MS pathogenesis is a period of subclinical AdoCbl deficiency over a period of many years resulting in production of odd-carbon-number fatty acids that are incorporated into myelin rendering it antigenic. The next step in MS pathogenesis is breach of the blood brain barrier thereby introducing leukocytes into the brain's blood supply resulting in T cell attack of antigenic myelin. All epidemiological clusters are regions wherein the major agricultural products are legumes that produce a high percentage of odd-carbon-number fatty acids and contain symbiotic rhizobia type bacteria in root nodules and in the soil. This novel etiological hypothesis is called "multiple sclerosis due to adenosylcobalamin deficiency" (MS-AdoCbl). Creation of realistic animal models based on the MS-AdoCbl hypothesis is presented. Methods for testing predictions made by the MS-AdoCbl hypothesis are described.

Back on the scent: the olfactory system in CNS demyelinating diseases

Olfactory dysfunction is recognised across an ever broadening spectrum of neuropsychiatric conditions including central nervous system (CNS) demyelinating diseases such as multiple sclerosis (MS) and neuromyelitis optica (NMO). In this review, we unravel the striking evidence highlighting how olfactory loss is a common clinical feature in MS and NMO. We provide an overview of the supportive psychophysical, electrophysiological, radiological and pathological data that point to the anatomical substrate of olfactory deficits in these diseases. The pattern of underlying pathology affecting the olfactory system is shown to be complex, involving multiple structures that are affected in different ways throughout the course of the disease. This review is the first to synthesise the expanding body of literature on the topic, provides novel insight into the way in which the olfactory system is affected in CNS demyelinating diseases, and raises intriguing questions about the role of this system in the pathogenesis of these diseases.

Olfactory dysfunction in Multiple Sclerosis: A scoping review of the literature

OBJECTIVE

Olfactory dysfunction in Multiple Sclerosis (MS) has been reported, but results have been inconsistent. In this review we describe, synthesize, and interpret the existing literature on olfactory dysfunction in Multiple Sclerosis and identify gaps in the current level of knowledge.

METHODS

The study design was a scoping review of the literature covering several study designs. Systematic Searches of the PubMed, CINAHL, Cochrane Library, Web of Science, PsycARTICLES, PsycINFO and Google Scholar databases were conducted that included key words related to Multiple Sclerosis and Olfaction Disorders. Literature that met the criteria of pertaining to both Multiple Sclerosis and olfactory dysfunction was identified, with the aim of providing an overview of the extent and types of research available in this area.

RESULTS

Sixty-one reports were identified in the initial search, with 40 meeting the study criteria. Twenty-five clinical studies were included. Among them, 23 studies measured for olfactory dysfunction in MS patients, ten evaluated MRI correlates of olfactory dysfunction, and five evaluated neurophysiology correlates of olfactory dysfunction. Six of the included studies were abstracts. In addition, thirteen reviews/commentaries and two case studies were included. The majority of the studies identified some degree of olfactory dysfunction in MS patients, and various aspects and correlations with olfactory impairment were observed.

CONCLUSIONS

The overall weight of the literature suggests that olfactory dysfunction may occur in MS. Although there is variability in reported frequency, the more robust studies suggest the prevalence is significant, ranging from 20% to 45% in the MS population. Despite this, the mechanisms are unknown and the clinical relevance of this association has not been well explored. Interesting findings relating mood disorders, cognition, and olfactory dysfunction in MS are also suggested but remain poorly developed and require further investigation. Future studies are also warranted to understand the dynamic changes in olfactory function during the course of MS, and to correlate olfactory function with relapses/disease activity.

Detection of olfactory dysfunction using olfactory event related potentials in young patients with multiple sclerosis

Background

Several studies reported olfactory dysfunction in patients with multiple sclerosis. The estimate of the incidence of olfactory deficits in multiple sclerosis is uncertain; this may arise from different testing methods that may be influenced by patients' response bias and clinical, demographic and cognitive features.

Aims

To evaluate objectively the olfactory function using Olfactory Event Related Potentials.

Materials and Methods

We tested the olfactory function of 30 patients with relapsing remitting multiple sclerosis (mean age of 36.03±6.96 years) and of 30 age, sex and smoking–habit matched healthy controls by using olfactory potentials. A selective and controlled stimulation of the olfactory system to elicit the olfactory event related potentials was achieved by a computer-controlled olfactometer linked directly with electroencephalograph. Relationships between olfactory potential results and patients' clinical characteristics, such as gender, disability status score, disease-modifying therapy, and disease duration, were evaluated.

Results

Seven of 30 patients did not show olfactory event related potentials. Sixteen of remaining 23 patients had a mean value of amplitude significantly lower than control group (p<0.01). The presence/absence of olfactory event related potentials was associated with dichotomous expanded disability status scale (p = 0.0433), as well as inversely correlated with the disease duration (r = −0.3641, p = 0.0479).

Conclusion

Unbiased olfactory dysfunction of different severity found in multiple sclerosis patients suggests an organic impairment which could be related to neuroinflammatory and/or neurodegenerative processes of olfactory networks, supporting the recent findings on neurophysiopathology of disease.

Olfactory threshold is impaired in early, active multiple sclerosis

Background: Olfactory dysfunction has been reported in multiple sclerosis (MS). However, to date no data are available on different qualities of olfactory function, namely odour identification, odour discrimination and odour perception threshold.

Objective: To assess different qualities of olfactory function in patients with MS and correlate these with demographic data, clinical data, depression, quality of life and cognitive functions.

Methods: In this cross-sectional study, 50 patients with MS or clinically isolated syndrome and 30 healthy controls were included. Olfactory function was measured using the Sniffin’ Sticks test.

Results: The scores for odour identification ( p = 0.001), odour perception threshold ( p = 0.037) and the combined score of odour identification, discrimination and perception threshold (TDI, p = 0.002) were significantly lower in MS. Hyposmia for identification ( p = 0.0017), threshold ( p = 0.017) and TDI score ( p = 0.0014) was more frequent in MS. Olfactory threshold was impaired in patients who were clinically active in the previous year ( p = 0.026) and in patients with a disease duration less than 2 years ( p = 0.0093). Identification score was negatively correlated with disease duration ( p = 0.0017). Olfactory function was not associated with disability, depression or quality of life.

Conclusions: We report evidence for qualitatively distinct hyposmia in MS, with increased smell threshold in the early inflammatory phases of the disease and impaired identification with a more widespread chronic disease.

Assessment of olfaction in multiple sclerosis: evidence of dysfunction by olfactory evoked response and identification tests

OBJECTIVE

To resolve whether the olfactory pathways are affected in multiple sclerosis.

METHODS

Olfaction was assessed by: (1) The University of Pennsylvania smell identification test (UPSIT, which uses microencapsulated odours that are released when scratched with a pencil) in 72 patients with multiple sclerosis and 96 controls, (2) olfactory evoked potentials (OEP) to 20 ppm H2S by volume, and 50% CO2 in air for 45 patients with multiple sclerosis and 47 controls. The abnormality rate in patients with multiple sclerosis for both tests (1) and (2) was compared with that for visual evoked potentials measured using a standard checquerboard technique.

RESULTS

By comparison with controls, patients exhibited significantly low scores on the smell identification test with 15% of patients scoring outside the 95% confidence intervals for controls. The UPSIT was occasionally abnormal when the visual evoked potential (VEP) was normal. In general UPSIT scores correlated well with the H2S-evoked response in controls and patients. For H2S, there was a statistically significant increase of latency and decrease of amplitude for patients compared with controls. Increased H2S latency and reduced UPSIT score correlated with greater disability on conventional rating scales. Overall, H2S responses were abnormal in about one quarter of patients with multiple sclerosis. The sensitivity of UPSIT and OEP was similar although disorder on one test did not necessarily indicate abnormality in the other. The visual evoked potential was found to be a more sensitive indicator of disease than OEP or UPSIT.

CONCLUSION

These findings confirm the existence of olfactory dysfunction in multiple sclerosis and validate a new evoked potential technique.

Tumor necrosis factor-alpha messenger RNA expression in patients with relapsing-remitting multiple sclerosis is associated with disease activity

We determined the cytokine messenger RNA (mRNA) expression pattern of blood mononuclear cells in 29 patients with relapsing-remitting multiple sclerosis every 4 weeks over a period of 12 months. During this period 27 relapses occurred in 14 patients (48%). Progression of disease activity as assessed by the occurrence of new lesions on nonenhancing T2-weighted magnetic resonance images of the head was detected in 12 (48%) of 25 patients. Using a semiquantitative polymerase chain reaction we demonstrated significant increases in tumor necrosis factor-alpha mRNA expression in peripheral blood mononuclear cells prior to a relapse. In 24 (85%) of 27 relapses increased tumor necrosis factor-alpha mRNA expression preceded clinical symptoms by 4 weeks. A similar pattern was observed for lymphotoxin mRNA expression. At the same time, transforming growth factor-beta and interleukin-10 mRNA levels declined. Fluctuations in the mRNA expression of tumor necrosis factor-alpha were also observed in 6 patients with stable disease who had active magnetic resonance scans on follow-up. No correlation of disease activity was observed with interleukin-1 beta, -4, or -6, inferferon gamma or endothelin-1 mRNA expression. From these data it can be concluded that variations in cytokine mRNA expression in blood mononuclear cells are correlated with disease activity in relapsing-remitting multiple sclerosis. It may be a valuable parameter to monitor the immunological status of patients in future clinical trials.

Myelin in multiple sclerosis is developmentally immature

The etiology of multiple sclerosis (MS) is considered to involve genetic, environmental, infective, and immunological factors which affect the integrity of a normally assembled myelin sheath, either directly or indirectly resulting in demyelination. In a correlative study involving protein chemical, mass spectrometric, and electron microscopic techniques we have determined that myelin obtained from victims of MS is arrested at the level of the first growth spurt (within the first 6 yr of life) and is therefore developmentally immature. The data supporting this conclusion include (a) the pattern of microheterogeneity of myelin basic protein (MBP); (b) the NH2-terminal acylation of the least cationic component of MBP ("C-8"); (c) the phase transition temperature (Tc) of myelin isolated from victims of MS correlated with the increased proportion of the least cationic component of MBP; and (d) immunogold electron microscopy using an antibody specific for "C-8" showed that the distribution of gold particles in a 2-yr-old infant was similar to the distribution found in a victim of MS. We postulate that this developmentally immature myelin is more susceptible to degradation by one or a combination of factors mentioned above, providing the initial antigenic material to the immune system.

Association of susceptibility to multiple sclerosis in Sweden with HLA class II DRB1 and DQB1 alleles

The association of MS with HLA class II alleles was studied by PCR-based typing of the DQA1, DQB1, DRB1, and DPB1 loci in 94 Swedish patients with relapses and remissions of the disease. The haplotype DRB1*1501-DQA1*0102-DQB1*0602 was found to be positively associated and three haplotypes were found to be negatively associated with MS. Linkage disequilibrium makes it difficult to assess whether DRB1 or DQB1 plays the primary role in the disease association, while the association with DPB1 and DQA1 appears to be secondary to that of DQB1 and DRB1. Two of the three haplotypes negatively associated with MS carry the DQB1*0301 allele. Also, the negatively associated DRB1*0401-DQA1*0301-DQB1*0301 haplotype differs from those with nonassociated DRB1*0401-DQA1*0301-DQB1*0302 haplotype only at DQB1. These results suggest that DQB1 alleles, as well as some DRB1 alleles, are involved in susceptibility and protection to MS. In searching for sequence motifs in the DR beta chain associated with MS susceptibility, all DRB1 alleles on haplotypes positively associated with MS, including the DRB1*1501, were found to encode a Val at position 86 of the DR beta chain. Also, DRB1 alleles that are negatively associated with MS all encode a Gly at position 86, suggesting that the residue at position 86 may be critical in conferring susceptibility and protection to MS. Finally, when the effect of the DRB1*1501 haplotype was removed there was no support for the hypothesis that MS is associated with a putative DQ-alpha beta heterodimer, encoded for by certain DQA1 and DQB1 alleles.

Brainstem glioma: I. Pathology, clinical features, and therapy

Gliomas that arise in the brain stem have been associated with a poor prognosis. Diagnostic neuroimaging readily identifies the tumor as it extends between normal brainstem structures. Histologic sampling of tumor with stereotactic methods is notoriously unreliable in establishing a definitive prognosis. Clinical trials that incorporate high-dose chemotherapy, autologous bone marrow rescue, and irradiation hold promise of better tumor control by overcoming the inaccessibility of the central nervous system to standard doses of chemotherapy. We review the pathology, clinical features, neuroimaging features, and current therapeutic concepts relative to brainstem glioma. The pediatric neurologist has a pivotal role in identifying and monitoring children with this malignancy.

Multiple sclerosis: does epidemiology contribute to providing etiological clues?

The epidemiological approach has undoubtedly contributed to our knowledge of Multiple Sclerosis (MS) by providing some etiological hypotheses in spite of the fact that a definitive basis for the conclusive resolution of its enigma is still lacking. Epidemiological studies have indicated that MS has an uneven geographical distribution and a changing incidence over time at least in several areas of the world: this suggests an etiological role of both genetic and environmental factors. The racial difference in disease risk, the results of familial and twin studies as well as the association between MS and some HLA markers, support the great importance of genetic factors. On the other hand, the evidence of temporal trends and the data from migrant studies seem to underline the etiological contribution of environmental factors. In the light of these results much of the present views have emerged interpreting the disease as caused by multiple factors acting at a susceptible age in genetically predisposed subjects.

An evaluation of the significance of areas of intense signal in the MR brain images of patients with multiple sclerosis

This study evaluates the distribution of areas of intense signal (AIS) in 189 patients with multiple sclerosis (MS) and 83 patients presenting high-risk factors of cerebrovascular injuries. Two multivariate statistical analyses (multifactorial discriminant analysis and logistic regression analysis) with two AIS scores and several subpopulations of patients (according to age and/or the number of AIS) were tested. The results of these analyses were expressed with the usual screening test. The results obtained in this study even without the help of any clinical information are very promising, since they established that the specificity of MRI could be improved by using the distribution of the AIS in the various anatomical areas as a criterion. Five regions of the brain display were particularly significant in the discrimination between MS and non-MS patients: In decreasing order we found that the temporal, occipital, brain stem, and parietal regions were more specific with respect to the diagnosis of MS, while only the basal ganglia could account for non-MS patients. With multifactorial discriminant analysis and logistic regression analysis respectively, 78.9 (+/- 2.8)% and 85.1 (+/- 2.8)% of the patients were correctly classified by MRI. The results obtained on the main group were confirmed by a predictive test carried out on an other population of 40 patients, which produced similar results. The comparison between our method and Fazekas's imaging criteria showed a 20% improvement in favour of our approach and it is hoped that it will contribute to make the most of MRI as a tool for the diagnosis of MS.

The dynamics of multiple sclerosis. The Charcot Lecture

The history of our understanding of the pathogenesis and pathophysiology of multiple sclerosis are reviewed in the context of Charcot's contribution. The implications for treatment of the new knowledge gained from studies during life of pathology and pathogenesis (by MRI) and pathophysiology (by evoked potentials) are reviewed.

Genetic susceptibility to multiple sclerosis linked to myelin basic protein gene

Genetic factors have been implicated in the aetiology of multiple sclerosis (MS), but the genes conferring susceptibility to MS have not been identified. We carried out genetic linkage and association analyses by studying polymorphism of the myelin basic protein (MBP) gene on chromosome 18, a candidate gene for MS, in 21 MS families, 51 additional unrelated patients with definite MS, and 85 controls. All subjects were Finnish, and 14 of the families were from an area with an exceptional familial clustering of MS. Magnetic resonance imaging (MRI) was used to examine subclinical disease in symptom-free family members. In the association analysis, the allele frequencies between MS patients and controls differed significantly, p = 0.000049), the difference being attributable mainly to a higher frequency of a 1.27 kb allele among patients. In the linkage analysis, based on an autosomal dominant model and penetrance 0.05, a maximum LOD score of 3.42 (theta = 0.00) was obtained when patients with optic neuritis and their symptom-free siblings with abnormal MRI findings were classified as "affected". When these subjects were classified as "unknown" the maximum LOD scores ranged from 2.99 to 3.25 (theta = 0.00). The results suggest that in this population genetic predisposition to MS is closely linked to the MBP gene and that polymorphism at the MBP locus or an adjacent locus has a role in the aetiology of MS.

The pathological evolution of multiple sclerosis

The new technique of nuclear magnetic resonance imaging (NMR) has been found to have particular value in the study of the evolution of the plaque of multiple sclerosis. Particularly when combined with gadolinium enhancement, the method not only shows very dramatically the waxing and waning of the plaque with time, it also demonstrates with remarkable clarity the important role of changes in vascular permeability in the pathological process. In this Annotation the ability of this technique to throw new light on the process of plaque formation and evaluation is critically assessed. In addition, the role of changing fluid content of the extracellular spaces of the CNS in influencing interpretation of the more conventional clinical and electrophysiological findings is discussed. While the method of NMR analysis does not yet show us how the plaque is initiated, it is suggested that future studies with these new techniques in the living subject may well lead us to rational therapeutic approaches based on pathogenetic mechanisms.

[Multiple sclerosis: objective criteria of diagnosis]

The frequency of multiple sclerosis in Brasil is assumed to be lower than in some geographically comparable regions, but internationally available objective diagnostic criteria are not generally used. We have reviewed a number of such criteria and applied those of Poser and colleagues to all patients who could be examined specifically for this study; who had been under our care between 1982-87; with clinically satisfactory history, physical exam, ancillary investigations and follow-up; with enough information to warrant immunosuppressive therapy with azathioprine, methyl-prednisolone or cyclophosphamide. There were 35 (88%) females and 5 (12%) males, with clinically definite (85%), probable (10%) disease according to Poser and cols, as well as 2 patients with chronic progressive disease. Age at time of study was 39 +/- 11 years, age at onset had been 32 +/- 10 years, and length of history was 6 +/- 7 years (mean +/- sd). Mode of onset was a disturbance of gait in 50%, of vision in 25% and dizziness in 10%. Physical exam at time of study showed motor deficits in 92.5%, sensory in 67.5%, ocular visual in 65%, spastic bladder in 35%, and vestibulo-cerebellar disturbances in 32%. Visual evoked responses were abnormal in 65% of 31 cases, auditory in 23% of 22 cases, and somatosensory in 80% of 20 cases. This study shows that international diagnostic criteria, specifically those of Poser and colleagues are applicable in Brasil, providing clear guidelines for diagnosis of multiple sclerosis. We suggest objective diagnostic criteria form the backbone of teaching about the disease, at various levels of medical education. Their wide utilization will in due time provide conditions for epidemiological, clinical and therapeutic studies which have not as yet been carried out in this country.

Methylprednisolone in multiple sclerosis exacerbation: changes in CSF parameters

Twenty-six patients with multiple sclerosis (MS) received a total of 45 courses of intravenous methylprednisolone daily for seven days, for acute neurological deterioration. Changes in CSF parameters and clinical status following methylprednisolone were determined and first and repeat courses were compared. There were significant reductions in CSF IgG, CSF albumin, serum IgG and serum albumin levels and CSF IgG synthesis rate in the first and repeat treatment groups. CSF IgG index fell significantly with initial methylprednisolone treatment but not with subsequent courses. Oligoclonal bands disappeared in three patients. Definite clinical improvement followed 30 methylprednisolone courses, possible improvement followed six and no change followed seven. Clinical response was not predicted by pre-treatment CSF IgG synthesis status and did not correlate with its degree of reduction.

A case-control epidemiological study of MS in the Paris area with particular reference to past disease history and profession

A retrospective case-control study was carried out on 230 patients with multiple sclerosis (MS) and 230 controls matched for year of birth and sex. The geographical distribution of residence of MS patients and controls was similar. Two peak ages of onset of MS were observed among woman patients (20-24, 30-34 years). There was no difference in histories of infectious diseases and autoimmune diseases between the two groups. A greater number of hairdressers was noticed among the patient group (p less than 0.05) and three patients (no control) had had professional contact with pathology specimens.

DNA length polymorphism 5' to the myelin basic protein gene is associated with multiple sclerosis

A site of DNA polymorphism linked to the myelin basic protein gene, identified as restriction fragment length polymorphism, was analyzed in a population-based study comparing patients with clinically definite multiple sclerosis (MS) and population-matched control subjects. A 0.9-kilobase (kb) genomic DNA fragment (EcoG) encompassing the first exon of the human myelin basic protein gene, located on the long arm of chromosome 18, identified ten alleles arising from a region of DNA, 1.5 kb 5' to the myelin basic protein gene first exon coding region. Produced by RsaI digests and ranging in length from 2.05 to 2.15 kb, these alleles vary in size by up to 100 base pairs due to insertion or deletion, or both, from a 1-kb length of repetitive DNA. Allele frequencies among 65 patients with MS were compared with those of 63 control subjects. Chi square for these data was significant (p less than 0.001), largely due to a preponderance in the patients with MS of alleles in the 2.14- to 2.15-kb range. Comparison of the numbers of patients with MS and control subjects bearing specific alleles showed that 45% of the patients carried at least one allele of 2.14 to 2.15 kb as opposed to 19% of control subjects (p less than 0.005). These data, while preliminary, suggest that patients with MS differ from population-matched control subjects with respect to DNA polymorphism linked to the myelin basic protein gene. Although no pathogenic relationship between this polymorphism and MS can be presupposed, this finding raises the possibility that the myelin basic protein gene or some other myelin basic protein-linked locus may be a factor in susceptibility to MS.

Natural killer cell number and activity in multiple sclerosis

Natural killer (NK) cell percentage among cells appearing in lymphocytic flow-cytometric gate, and their concentration per unit volume of peripheral blood, as well as NK-cell in vitro activity, were determined in 45 patients with multiple sclerosis (MS, 34 with definite and 11 with probable diagnosis). Two age- and sex-matched control groups consisted of 27 healthy individuals and 19 individuals with other neurological diseases, respectively. NK cells were identified on the basis of their reaction with monoclonal antibody NKH-1, and NK-activity on the basis of their spontaneous killing of K-562 erythroleukemia target cells with mononuclear cells from peripheral blood. MS patients were analyzed in regard to the phase (active, stable inactive, stable progressive) and course (remittent, remittent-progressive, progressive) of the disease. In general, MS patients tended to have both lower number and activity of natural killer cells than either of the two control groups. A statistically significant decrease was found for the concentration of NKH-1+ cells in the blood of all MS patients, for the number of lymphocytes in the blood of patients with remittent course of the disease, and for the number of NKH-1+ cells in the blood of patients with progressive course of the disease. It appeared that more profound defects were associated with the progression of the disease; NK-cell number always appeared more affected than NK-cell activity. In MS patients, NK-cell activity correlated significantly with NK-cell percentages among lymphocytes but poorly with the concentration of NKH-1+ cells in the blood. In healthy controls, neither of the two correlations was significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Diagnostic investigations in MS: which is the most sensitive?

In an attempt to establish the efficacy of the different diagnostic tests, 41 multiple sclerosis (MS) patients at different stages of the disease were studied by means of visual evoked potential (VEP) recording, T-lymphocyte subset determination cerebrospinal fluid (CSF) analysis and magnetic resonance (MR) imaging. MR and CSF oligoclonal bands (OB) were the most sensitive techniques for the diagnosis of MS, being positive in 88% of patients, while VEP and helper/suppressor (H/S) T-cell ratio were altered in 54% and 46% of patients respectively. Low significant agreement coefficient were found among the 4 tests and the major value, even though "fairly" significant, was between MR and OB.

An allelic cluster of DQ alpha restriction fragments is associated with multiple sclerosis: evidence that a second haplotype may influence disease susceptibility

Extensive analysis of restriction fragment length polymorphism using HLA class II and T-cell receptor gene probes has been carried out in an attempt to identify genetic markers more strongly associated with multiple sclerosis than the classically defined antigens DR2, Dw2, and DQw1. The use of DNA pooled from groups of patients and controls from northeast Scotland enabled the screening of 14 restriction endonucleases with five HLA-D region probes (DP alpha, DP beta, DQ alpha, DQ beta, DR beta) and two T-cell antigen receptor probes. Restriction fragment length polymorphisms which discriminated between multiple sclerosis and control pools were identified with four restriction enzymes: Msp1 (DQ alpha), BamH1, Bgl11, and Taq1 (DQ beta). No discriminatory polymorphism was seen with any of the other enzyme/probe combinations. Subsequent Southern blot analysis of individual DNA samples was carried out using these enzymes and probes in two independently conducted studies, in Northern Ireland and northeast Scotland. Following Msp1-digestion and hybridization to DQ alpha, a 3.25-kb fragment was observed in 31% of Scottish patients but in only 4% of controls from the same population. Furthermore, when only DR2-positive individuals were analyzed, there was a significant excess of this fragment in patients from both Scotland (28, or 2.9%) and Northern Ireland (20, or 3.4%). Although the DQ alpha gene characterized by this fragment remains to be determined, this fragment exhibits apparent allelism to DQw1. Therefore, these data raise the possibility that two different DQ alleles, one on each haplotype, may jointly contribute to disease susceptibility.

Positive autoradiographic findings in brains of four MS patients

Autoradiography of brain slices from 4 multiple sclerosis (MS) and 9 control patients was performed. After 6 weeks of exposure the exact picture of the white matter appeared on the X-ray films in all cases with MS, but only in one of the controls. The high level of autoradiographic signal from MS white matter suggests that an abnormal accumulation of radioactive trace elements takes place within the brains of MS victims.

Quantitative magnetic resonance imaging in multiple sclerosis: the effect of high dose intravenous methylprednisolone

Magnetic resonance imaging was performed on 50 patients with clinically definite or probable multiple sclerosis before and 15 days after starting treatment with intravenous methylprednisolone (0.5 g daily for 5 days). Scans were abnormal in 49 patients. New lesions had appeared on the second scan in nine individuals and in seven a single pre-existing lesion appeared to have become smaller but in no case were lesions seen to disappear. Two patients showed both reduction in the size of an abnormal area and development of a single new lesion indicating that corticosteroids do not appear rapidly to alter the process underlying plaque formation. Measurements of relaxation times were performed in 12 randomly selected patients. All showed elevated values in normal appearing white matter but not cortex before treatment compared with 18 healthy controls. After treatment a significant decrease of T1 and T2 was observed in cortex, and of T1 alone in normal appearing white matter. No significant change could be detected within lesions, a finding attributed to the wide range of relaxation values observed at these sites before treatment. Since brain water content is increased in normal appearing white matter of multiple sclerosis patients, and is significantly reduced by high-dose methylprednisolone, resolution of oedema may contribute to the rapid spontaneous or corticosteroid induced symptomatic recovery that characterises the disease in its early stages.

DNA repair, sensitivity to gamma radiation and to heat shock in lymphocytes from acute, untreated multiple sclerosis patients

Increases in spontaneous sister chromatid exchange (SCE) and gamma radiation-induced chromosome aberrations have been reported in peripheral blood lymphocytes (PBL) from multiple sclerosis (MS) patients, suggesting the presence of an abnormality in repair in this disease. We tested this hypothesis by measuring the ability to repair DNA and survival, after exposure to low (2-12 Gy) and high (100 Gy) gamma ray doses or to a high temperature (37-45 degrees C), of freshly isolated PBL from 15 patients affected by definite MS and 15 healthy subjects. The MS patients were untreated and in the acute phase of the disease. No significant difference was found between the two groups. We suggest that the previously reported genomic instability may be of viral origin and not due to a genetic defect in repair of DNA in these patients.

The significance of the inflammatory reactions for the development of clinical signs in multiple sclerosis and acute experimental autoimmune encephalomyelitis as assessed by means of the spontaneous chemiluminescence activity of peripheral blood monocytes

We found that the course of the chemiluminescence activity (CL-A) of peripheral blood monocytes of Lewis rats with acute experimental autoimmune encephalomyelitis (EAE) correlates well with the clinical course of this autoimmune disease and that only a reduction in T helper cells caused a reduction in CL-A. However, in multiple sclerosis (MS) patients the CL-A increased when clinical improvement started. The serum of these patients contained at least two stimulatory substances. More than 50% of the stimulatory effect could be blocked by antibodies to interferon-gamma.

Detection of DNA transcripts of measles genes in multiple sclerosis brain tissue by transfection

Transfection studies on DNA obtained from 16 multiple sclerosis (MS) and 13 non-MS brain tissues suggested that 3/16 (19%) MS and 3/13 (23%) non-MS samples contained contaminating measles virus double-stranded RNA, and that 6/16 (38%) MS and 0/13 non-MS samples contained DNA transcripts of measles genes. It is argued that the DNA transcripts most probably originated from dual retrovirus and measles infections in the subjects.

A follow-up study of very low field MRI findings and clinical course in multiple sclerosis

Seventy-three consecutive patients with definite multiple sclerosis (MS) were examined with very low field (0.17 and 0.02 tesla) magnetic resonance imaging (MRI) of the brain. Fifty-seven patients were examined a second time after 6 months, 41 patients a third time after 1 year, and 25 patients a fourth time after 2 years. The initial finding was abnormal in 57/73 patients (78%). The number of lesions increased with age, duration of disease, and increasing disability. Plaques were more numerous in progressive than in remitting MS. Of the patients with abnormal MRI 65% had more than 3 lesions, and in 82% lesions were smaller than 2.5 cm in diameter. After follow-ups of 1 year and 2 years the size of MRI lesions remained unchanged in 55% and 64%, respectively. Unchanged plaque numbers were found in 72% and 60%. Unchanged MRI was most common among patients with remitting MS who were in a stable phase. Decrease in size and disappearance of plaques correlated well with clinical remissions. Increase in size was rare even during relapses. New plaques could appear during all phases of clinical course although they reflected better a relapse of remitting or progressive disease.

Familial multiple sclerosis

Siblings of patients with multiple sclerosis have an increased risk of developing the disease. In this report we describe 3 families with multiple affected members, representing the largest published aggregation of cases in first degree relatives. In the 2 families in which HLA tissue-typing was performed the affected individuals shared part of the haplotype HLA-DR2 (+ HLA-DQW1), BfS (+ C2C), C4A3, C4B1. The implications of these findings for the aetiology of multiple sclerosis are discussed.

Multiple sclerosis: a survey of alternative hypotheses concerning aetiology, pathogenesis and predisposing factors

There is abundant evidence that both environmental and genetic factors play a role in the aetiology and pathogenesis of multiple sclerosis. Currently, a virus infection and an abnormality of T-cell function are favoured candidates for the environmental and genetic factors, respectively. However, as long as convincing evidence for a specific viral infection and for a pathogenetic role for T-cells in multiple sclerosis is lacking, it may be worthwhile to consider alternative hypotheses that have been proposed in recent years. These have been classified in this review under the headings Toxins, Dietary and Metabolic Abnormalities, Embolism, Infection, and Immunological Mechanisms.

The epidemiology of multiple sclerosis in Queensland, Australia

An epidemiological survey of multiple sclerosis (MS) in the State of Queensland was undertaken with its prevalence day being the national census day on June 30th, 1981, 20 years after a regional survey within the State. The relationship between increasing prevalence of MS and increasing south latitude within the State of Queensland which was suggested by the 1961 study was confirmed in the present study. The prevalence rate had increased significantly over the 20-year period between the studies but the State remained a medium frequency zone for MS (prevalence rate between 5 and 29 per 100,000 of population). Although a real increase in disease frequency could not be excluded as a contributing factor to the rise in prevalence, it was most likely due predominantly to an increase in life expectancy amongst the MS population and also in differential migration of a population at a greater risk of developing MS than the indigenous population. The proportions of Australian-born patients who had migrated to Queensland from the higher risk southern regions of Australia or travelled overseas to countries known to be high-risk for MS prior to disease onset, had fallen between the two surveys thus exerting, if anything, a negative influence on the change in prevalence. Analysis of MS prevalence rates amongst migrant populations in Queensland as compared to the more southerly city of Perth in Western Australia, suggested that the risk of acquisition of MS may extend over a wider age range than is generally accepted. Finally, there was an absence of MS cases amongst the Aboriginal population in Queensland but it can only cautiously be concluded from this study that the disease is rare in these peoples.

Peripheral neuropathy associated with sicca syndrome

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Incidental subcortical lesions identified on magnetic resonance imaging in the elderly. I. Correlation with age and cerebrovascular risk factors

Patchy subcortical foci of increased signal intensity are frequently identified on magnetic resonance imaging (MRI) in the elderly. The incidence and clinical correlates of these lesions remain unknown. In this report, 240 consecutive MRI scans performed over a 6-month period were reviewed (excluding patients with recent brain trauma or known demyelinating disease). Subcortical incidental lesions (ILs) were identified, which could not be accounted for by the patient's current clinical diagnosis, neurological status, or CT scan. The ILs were graded according to size, multiplicity, and location. The incidence and severity of ILs increased with advancing age (p less than 0.0005). Among patients over 50 years of age, the incidence and severity of ILs were correlated with a previous history of history of ischemic cerebrovascular disease (p less than 0.05) and with hypertension (p less than 0.05). Multivariable regression analysis identified age, prior brain ischemia, and hypertension as the major predictors of ILs in the elderly. Diabetes, coronary artery diseases, and sex did not play a significant role. With the exception of cerebrovascular disease, there was no association between ILs and any particular clinical entity, including dementia. It is concluded that subcortical parenchymal lesions are frequent incidental findings on MRI in the elderly, and may represent an index of chronic cerebrovascular diseases in such patients.

Incidental subcortical lesions identified on magnetic resonance imaging in the elderly. II. Postmortem pathological correlations

The pathological correlates of subcortical lesions noted on magnetic resonance imaging (MRI) in the elderly are not known. Postmortem in vitro proton MRI was performed on the brains of seven consecutive elderly patients dying of nonneurologic causes. Scans were done in the fresh and fixed states with the specimen immersed in saline and formaldehyde respectively. A 1.5 Tesla superconductive system was used with a multiple spin-echo protocol generating T2 weighted images. Subcortical MRI lesions were localized in three dimensions and identified at brain cutting. In addition, pathological correlations were obtained from an eighth patient who underwent MRI eleven days before death. Histological examinations were performed in a blinded fashion, including control areas from the same brains. Subcortical MRI lesions were found to be associated with arteriosclerosis, dilated perivascular spaces, and vascular ectasia (p less than 0.05). These histological changes were characteristic of "état criblé" which, like subcortical MRI lesions, is associated with age and hypertension. Shrinkage (or atrophy) of the brain parenchyma around ectatic blood vessels would result in an extensive network of tunnels filled with extracellular water. The proton MRI signal from such areas of the brain would be increased. Gliosis and small areas of infarction occasionally coexisted with "état criblé," but these were not present in all areas with MRI lesions and could not be distinguished by MRI signal alone. In conclusion, clinical and pathological correlations lend support to the uniform hypothesis that MRI provides a nonspecific index of brain parenchymal alterations caused by aging and chronic cerebrovascular disease.

Disseminated lesions at presentation in patients with optic neuritis

Thirty five adults and two children with clinically isolated optic neuritis were examined by magnetic resonance imaging (MRI) to determine the presence of disseminated lesions within the brain at presentation and to compare these findings with the results of evoked potential studies. Of the adult patients, 61% showed lesions on the scans whereas the evoked potentials suggested the presence of lesions outside the visual system in 30%. MRI is a sensitive method for the demonstration of clinically unsuspected lesions in patients with uncomplicated optic neuritis.