Cannabis-Based Medicine for Neuropathic Pain and Spasticity-A Multicenter, Randomized, Double-Blinded, Placebo-Controlled Trial

Patients with multiple sclerosis (MS) and spinal cord injury (SCI) commonly sustain central neuropathic pain (NP) and spasticity. Despite a lack of consistent evidence, cannabis-based medicine (CBM) has been suggested as a supplement treatment. We aimed to investigate the effect of CBM on NP and spasticity in patients with MS or SCI. We performed a randomized, double-blinded, placebo-controlled trial in Denmark. Patients aged ≥18 years with NP (intensity >3, ≤9 on a numerical rating scale (NRS0-10) and/or spasticity (>3 on NRS0-10) were randomized to treatment consisting of either delta-9-tetrahydrocannabinol (THC), cannabidiol (CBD), a combination of THC&CBD in maximum doses of 22.5 mg, 45 mg and 22.5/45 mg per day, respectively, or placebo. A baseline registration was performed before randomization. Treatment duration was six weeks followed by a one-week phaseout. Primary endpoints were the intensity of patient-reported NP and/or spasticity. Between February 2019 and December 2021, 134 patients were randomized (MS n = 119, SCI n = 15), where 32 were assigned to THC, 31 to CBD, 31 to THC&CBD, and 40 to placebo. No significant difference was found for: mean pain intensity (THC 0.42 (-0.54-1.38), CBD 0.45 (-0.47-1.38) and THC&CBD 0.16 (-0.75-1.08)), mean spasticity intensity (THC 0.24 (-0.67-1.45), CBD 0.46 (-0.74-1.65), and THC&CBD 0.10 (-1.18-1.39), secondary outcomes (patient global impression of change and quality of life), or any tertiary outcomes. We aimed to include 448 patients in the trial; however, due to COVID-19 and recruitment challenges, fewer were included. Nevertheless, in this four-arm parallel trial, no effect was found between placebo and active treatment with THC or CBD alone or in combination on NP or spasticity in patients with either MS or SCI. The trial was registered with the EU Clinical Trials Register EudraCT (2018-002315-98).

The Effect of Cannabis-Based Medicine on Neuropathic Pain and Spasticity in Patients with Multiple Sclerosis and Spinal Cord Injury: Study Protocol of a National Multicenter Double-Blinded, Placebo-Controlled Trial

Disease or acquired damage to the central nervous system frequently causes disabling spasticity and central neuropathic pain (NP), both of which are frequent in multiple sclerosis (MS) and spinal cord injury (SCI). Patients with MS and SCI often request treatment with cannabis-based medicine (CBM). However, knowledge about effects, side effects, choice of active cannabinoids (Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD) alone or in combination), and doses of CBM remains limited. Using a double-blind, parallel design in a national multicenter cohort, this study examines the effect of CBM on spasticity and NP. Patients are randomized to treatment with capsules containing either THC, CBD, THC and CBD, or placebo. Primary endpoints are patient-reported pain and spasticity on a numerical rating scale. Other endpoints include quality of life and sleep, depression and anxiety, and relief of pain and spasticity. Side-effects of CBM are described. In a sub-study, the pharmacodynamics (PD) and pharmacokinetics (PK) of oral capsule CBM are examined. We expect that the study will contribute to the literature by providing information on the effects and side-effects of CBD, THC, and the combination of the two for central neuropathic pain and spasticity. Furthermore, we will describe the PD/PK of THC and CBD in a patient population.

Circulating levels of tight junction proteins in multiple sclerosis: Association with inflammation and disease activity before and after disease modifying therapy

BACKGROUND

Tight junction proteins contribute to maintenance of epithelial and endothelial barriers such as the intestinal barrier and the blood brain barrier (BBB). Increased permeability of these barriers has been linked to disease activity in MS and there is currently a lack of easily accessible biomarkers predicting disease activity in MS.

AIM

To investigate whether levels of circulating tight junction proteins occludin and zonula occludens-1 (ZO-1) are associated with biomarkers of inflammation and disease activity; and to determine whether they could serve as clinical biomarkers.

METHODS

We prospectively included 72 newly diagnosed patients with relapsing remitting MS or clinically isolated syndrome with no prior disease modifying therapy (DMT) use and 50 healthy controls (HCs). Patients were followed with blood samples, 3 tesla MRI, and clinical evaluation for 12 months. Occludin, ZO-1, calprotectin and soluble urokinase-type plasminogen activator receptor (suPAR) were measured by ELISA; serum neurofilament light (NfL) and IL-6 by single-molecule array (SIMOA). The mRNA expression of IFNG, IL1R1, IL10, IL1B, ARG1 and TNF was measured by quantitative real time polymerase chain reaction (qPCR) in whole blood.

RESULTS

Plasma occludin levels were higher in MS patients compared with HCs. After 12 months on DMT, occludin levels were reduced by approximately 25% irrespective of 1st or 2nd line DMT (p<0.001). Furthermore, NfL and calprotectin levels were significantly reduced by 31% and 29%, respectively. Occludin and ZO-1 did not correlate with biomarkers of inflammation and did not predict disease activity at baseline or after 12 months.

CONCLUSIONS

Higher levels of occludin suggest an increased permeability of the BBB and/or the intestinal barrier in MS patients. The reduction of occludin after 12 months on DMTs might reflect repair of these barriers upon treatment. However, plasma levels of ZO-1 and occludin could not predict clinical or MRI disease activity as determined by regression and ROC-curve analysis. Our results do not indicate a clear clinically relevant role for circulating tight junction proteins as biomarkers of disease activity in MS and further investigations in larger cohorts are needed to clarify this issue.

Neutrophil-to-lymphocyte ratio and CRP as biomarkers in multiple sclerosis: A systematic review

Multiple sclerosis (MS) is a chronic immune-mediated disease of the central nervous system, which causes demyelination and neuroaxonal damage. Low-grade systemic inflammation has been suggested to contribute to the pathogenesis due to amplification of pathogenic immune activation. However, there is a lack of reliable biomarkers of systemic inflammation predicting disease activity and progression in MS. The neutrophil-to-lymphocyte ratio (NLR) and C-reactive protein (CRP) have been identified as biomarkers of severity and disease activity in various disorders. In September 2020, we conducted a systematic literature search on multiple databases on studies reporting NLR values or CRP levels in MS. The aim of this systematic review was to highlight the current knowledge about the potential of NLR and CRP as biomarkers in MS. A total of nineteen articles qualified for inclusion. Data on CRP were included in fourteen studies and NLR in nine studies. The results regarding CRP were inconsistent, and present literature does not support the use of CRP as a diagnostic or prognostic biomarker in MS. In contrast, NLR values were increased in MS patients compared with healthy controls in all case-control studies. Furthermore, NLR was associated with disease activity in untreated patients. Our systematic review therefore indicates that NLR might serve as a potential biomarker of disease activity. Given that the results of NLR are mainly drawn from retrospective case-control or cross-sectional studies, future prospective studies with long-term follow-up are required to accurately determine optimal timing and cutoff values that may be used in the clinical setting.

A novel neurodegenerative spectrum disorder in patients with MLKL deficiency

Mixed lineage kinase domain-like (MLKL) is the main executor of necroptosis, an inflammatory form of programmed cell death. Necroptosis is implicated in combating infections, but also in contributing to numerous other clinical conditions, including cardiovascular diseases and neurodegenerative disorders. Inhibition of necroptosis is therefore of therapeutic interest. Here we report two siblings both of whom over the course of 35 years developed a similar progressive, neurodegenerative spectrum disorder characterized by paresis, ataxia and dysarthria. Magnetic resonance imaging of their central nervous system (CNS) revealed severe global cerebral volume loss and atrophy of the cerebellum and brainstem. These brothers are homozygous for a rare haplotype identified by whole genome sequencing carrying a frameshift variant in MLKL, as well as an in-frame deletion of one amino acid in the adjacent fatty acid 2-hydroxylase (FA2H) gene. Functional studies of patient-derived primary cells demonstrated that the variant in MLKL leads to a deficiency of MLKL protein resulting in impairment of necroptosis. Conversely, shotgun lipidomic analysis of the variant in FA2H shows no impact on either the abundance or the enzymatic activity of the encoded hydroxylase. To our knowledge, this is the first report of complete necroptosis deficiency in humans. The findings may suggest that impaired necroptosis is a novel mechanism of neurodegeneration, promoting a disorder that shares some clinical features with primary progressive multiple sclerosis (PPMS) and other neurodegenerative diseases. Importantly, the necroptotic deficiency does not cause symptoms outside the nervous system, nor does it confer susceptibility to infections. Given the current interest in pharmacological inhibition of necroptosis by targeting MLKL and its associated pathways, this strategy should be developed with caution, with careful consideration of the possible development of adverse neurological effects.

Exposure to passive smoking during adolescence is associated with an increased risk of developing multiple sclerosis

BACKGROUND

Environmental factors are associated with acquiring multiple sclerosis (MS) particularly in adolescence.

OBJECTIVE

To test for association between MS and exposure to passive smoking at the age of 10-19.

METHODS

A total of 919 patients from the Danish MS Registry and Biobank and 3419 healthy blood donors who had not smoked before the age of 19 were targeted. We analyzed separately for each sex and for those never-smokers (cohort 1) and active smokers above the age of 19 (cohort 2). All participants completed standardized questionnaires about smoking and lifestyle. We matched cases and controls in the ratio of 1:2 by propensity scores discarding unmatchable individuals and used logistic regression adjusted for all covariates and interactions.

RESULTS

After matching, we included 110/213 male cases/controls and 232/377 female case/controls in cohort 1. In cohort 2, the numbers were 160/320 and 417/760, respectively. Among women in cohort 1, the odds ratio (OR) for MS by passive smoking at the age of 10-19 was 1.432 (p = 0.037) but in men it was 1.232 (p = 0.39). Among men in cohort 2, OR was 1.593 (p = 0.022) but among women it was only 1.102 (p = 0.44).

CONCLUSION

Among never smokers, female MS cases were more often than female controls reported with passive smoking between the age of 10 and 19, and among smokers above the age of 19, male MS patients were more often than male controls reported with passive smoking.

Short-chain fatty acids and gut microbiota in multiple sclerosis

BACKGROUND

Multiple Sclerosis (MS) is a chronic immune-mediated neurological disease of the central nervous system with a complex and still not fully understood aetiology. In recent years, the gut microbiota and fermentative metabolites like short-chain fatty acids (SCFAs) have received increased attention in relation to the development and disease course of MS. This systematic review highlights and summarizes the existing literature within this field.

METHODS

A systematic search in PubMed was conducted on 12 October 2017, to find published original studies on SCFAs and their impact on MS and the animal model of MS experimental autoimmune encephalomyelitis (EAE). Furthermore, all studies analysing the gut microbiota in MS patients were included. A total of 14 studies were eligible for this review.

RESULTS

Short-chain fatty acids have been shown to ameliorate the disease course in EAE, but no studies specifically addressing the role of SCFAs in human MS patients were identified. However, some investigations have shown that the microbiota of MS patients is characterized by a reduction in SCFA-producing bacteria.

CONCLUSIONS

Studies of EAE in mice suggest that SCFAs may play a role in the development and progression of EAE, but so far this has not been confirmed in humans. An aberrant gut microbiota in MS patients has been reported to be differentially abundant compared with healthy controls, although with little consistency in the bacterial taxa. Further investigations are required to elucidate the involvement of the gut microbiota and its metabolites, including potential beneficial effects of SCFAs, in the development and course of MS.

The neutrophil-to-lymphocyte ratio is associated with multiple sclerosis

Background

Subtypes of white blood cell counts are known biomarkers of systemic inflammation and a high neutrophil-to-lymphocyte ratio (NLR) has been associated with several autoimmune diseases. Few studies have investigated the NLR in multiple sclerosis (MS).

Objective

To examine the association between NLR, MS and disability measured by the MS severity score (MSSS).

Methods

Patients were included from the Danish Multiple Sclerosis Biobank. Information on patient NLR was obtained just before their first treatment and clinical information was provided by the Danish Multiple Sclerosis Treatment Register. Information on NLR from controls was collected from the Danish Blood Donor Study. Patients and controls were 1:2 propensity score matched by baseline confounders.

Results

Propensity score matching left 740 of 743 MS patients and 1420 of 4691 controls for further analyses. Odds-ratio (OR) was 3.64 (95% confidence interval 2.87–4.60, p < 0.001) for MS disease per unit increase of logarithmically transformed NLR (ln-NLR), corresponding to an OR of 2.68 for each doubling of NLR. Mean NLR was 2.12 for patients and 1.72 for controls (p < 0.001). Ln-NLR correlated weakly with patient MSSS (R² = 0.019, p = 0.008).

Conclusion

Patients with early MS had increased levels of NLR compared to healthy controls and NLR was weakly correlated with MSSS.

Alcohol consumption in adolescence is associated with a lower risk of multiple sclerosis in a Danish cohort

BACKGROUND AND OBJECTIVE

Due to the possible existence of a vulnerable period of multiple sclerosis (MS) susceptibility in adolescence and because Danish teenagers have a high alcohol consumption, we investigated the association between alcohol consumption at ages 15-19 and the risk of developing MS.

METHODS

A total of 1717 patients with MS and 4685 healthy blood donors filled in a comprehensive environmental and lifestyle questionnaire. Data were analysed by logistic regression models and adjusted for selected confounders.

RESULTS

We found an inverse association between alcohol consumption in adolescence and risk of developing MS in both women (p < 0.001) and men (p = 0.012). Women with low alcohol consumption had an odds ratio (OR) of 0.56 (95% confidence interval (CI): 0.47-0.66) compared with non-drinking women. The ORs were similar for women with moderate (OR = 0.49, 95% CI: 0.38-0.62) and high consumption (OR = 0.57, 95% CI: 0.38-0.84). Men with low alcohol consumption had an OR of 0.69 (95% CI: 0.53-0.89) compared with non-drinking men but no decreased risk was found for men with moderate and high consumption.

CONCLUSION

Alcohol consumption in adolescence was associated with lower risk of developing MS among both sexes.

Prognostic value of cerebrospinal fluid neurofilament light chain and chitinase-3-like-1 in newly diagnosed patients with multiple sclerosis

BACKGROUND

Neurofilament light chain (NFL) and chitinase-3-like-1 (CHI3L1) concentrations in cerebrospinal fluid (CSF) may have prognostic value in clinically isolated syndromes (CIS) and relapsing-remitting multiple sclerosis (RRMS).

OBJECTIVES

To compare the prognostic value of CSF concentrations of NFL and CHI3L1 in newly diagnosed CIS and RRMS patients.

METHODS

NFL and CHI3L1 were measured in CSF in 177 newly diagnosed patients with CIS or RRMS who were followed clinically for a mean of 5.7 years.

RESULTS

At baseline CSF concentrations of NFL correlated with CSF concentrations of CHI3L1, relapses in the previous year, time from last relapse, and the Expanded Disability Status Scale (EDSS) score. CSF concentrations of NFL and CHI3L1 were both associated with increased relapse risk during the first 2 years in univariate analyses, but only the CSF concentration of NFL was independently associated with relapse risk in a multivariable analysis. There was no relationship between CSF concentrations of NFL or CHI3L1 and risk of conversion to secondary progressive MS or development of disability.

CONCLUSION

CSF concentrations of NFL are associated with 2-year relapse risk but not with disease progression or clinical worsening in newly diagnosed CIS and RRMS patients. This may be due to confounding by the effect of disease-modifying therapies.

Smoking is associated with increased disease activity during natalizumab treatment in multiple sclerosis

Background:

Smoking has been associated with increased multiple sclerosis (MS) risk, disease worsening, and progression in MS patients. Furthermore, interactions between smoking and human leukocyte antigen (HLA) genes have been shown for MS risk. Recently, we found that smoking was associated with an increased relapse rate in interferon-beta-treated relapsing-remitting multiple sclerosis (RRMS) patients.

Objectives:

We examined the association between smoking and relapses in natalizumab-treated RRMS patients. Second, we investigated if an interaction between smoking and HLA-DRB1*15:01 or HLA-A*02:01 affected the number of relapses during treatment.

Methods:

In this observational cohort study, 355 natalizumab-treated RRMS patients were assessed. Prespecified criteria excluded 62 patients. Clinical data from the starting of treatment to the two-year follow-up visit were collected. Smoking status was obtained by a questionnaire survey. TaqMan allelic discrimination was used for genotyping of tag single-nucleotide polymorphisms (SNPs) for HLA-DRB1*15:01 and HLA-A*02:01. Negative binomial regression analysis was used to analyze the association between relapse rate and smoking intensity and HLA.

Results:

One pack of cigarettes (20 cigarettes) per day during natalizumab treatment increased the relapse rate during treatment with 38% (incidence rate ratio (IRR) = 1.38, 95% confidence interval (CI): 1.08–1.77, p = 0.01). No association or interaction was found between smoking and HLA-DRB1*15:01 or HLA-A*02:01, respectively.

Conclusion:

Smoking intensity was significantly associated with the number of relapses during natalizumab treatment.

Genetic burden of MS risk variants distinguish patients from healthy individuals but are not associated with disease activity

Weighted genetic risk score (wGRS) was analysed for association with disease activity in more than 500 MS patients before and during interferon-beta treatment. The wGRS was higher in MS patients than in healthy controls when analysing eight HLA - and 109 non-HLA MS risk gene variants. No significant associations were observed between number of relapses prior to or during treatment with interferon-beta, both with and without HLA risk alleles included in the wGRS. In conclusion, among Danes the wGRS was higher in MS patients than controls but was not associated with the overall disease activity or response to treatment with interferon-beta.

Soluble serum VCAM-1, whole blood mRNA expression and treatment response in natalizumab-treated multiple sclerosis

BACKGROUND

Natalizumab reduces disease activity in multiple sclerosis (MS). Natalizumab binds to the very late antigen-4 and inhibits vascular cell adhesion molecule-1 (VCAM-1)-mediated transmigration of immune cells across the blood-brain-barrier. This is associated with decreased serum concentrations of soluble (s)VCAM-1 and an altered composition of immune cell-subsets in the blood.

OBJECTIVE

We aimed to examine if sVCAM-1 serum concentrations and whole blood mRNA expression levels of immune activation biomarkers is associated with disease activity in natalizumab-treated MS-patients.

METHODS

sVCAM-1 serum concentrations and whole blood mRNA expression were measured in blood samples from untreated RRMS-patients and from two independent groups of natalizumab-treated patients.

RESULTS

sVCAM-1 serum concentrations and whole blood expression of HLX1 and IL1B mRNA were lower, whereas expression of EBI3 mRNA was higher in natalizumab-treated MS-patients. Five genes were differentially expressed in clinically unstable natalizumab-treated MS-patients in the discovery but not in the validation group.

CONCLUSION

Decreased serum concentrations of sVCAM-1 and altered whole blood mRNA expression levels of a panel of immunomarkers, associated with natalizumab-treatment, are not sensitive markers of MS disease activity. However, decreased expression of pro-inflammatory HLX1 and IL1B and increased expression of immunoregulatory EBI3 may indicate a less pathogenic immune activation status in natalizumab-treated MS.

Vitamin D supplementation reduces relapse rate in relapsing-remitting multiple sclerosis patients treated with natalizumab

BACKGROUND

Vitamin D insufficiency is common among multiple sclerosis patients, and hypovitaminosis D has been associated with multiple sclerosis (MS) risk and disease activity.

OBJECTIVE

To investigate how recommendations on vitamin D3 supplements affect 25-hydroxyvitamin D (25(OH)D) levels in patients with relapsing-remitting MS (RRMS) and to examine the clinical effects associated with changes in 25(OH)D levels.

METHODS

In this prospective cohort study, baseline blood samples were collected from 170 natalizumab-treated RRMS patients during winter 2009-2010 and were repeated the following winter. Vitamin D supplements were recommended according to standard clinical practice in our clinic to patients with serum 25(OH)D<50nmol/l at baseline. Information was obtained on annualized relapse-rate (ARR) the year prior to baseline and the following year.

RESULTS

We found that recommending vitamin D supplements in patients with vitamin D insufficiency was associated with a significant increase in serum 25(OH)D concentrations (p=5.1×10^-10), which was significantly related with decreases in ARR; for each nmol/l increase in Δ25(OH)D a -0.014 (95% CI -0.026 to -0.003) decrease in ΔARR was observed, p=0.02.

CONCLUSION

Correction of hypovitaminosis D in clinical practice by recommending oral D3 supplements resulted in increases in 25(OH)D levels in serum, which were associated with decreases in ARR in RRMS.

Shift work at young age is associated with increased risk of multiple sclerosis in a Danish population

BACKGROUND

Epidemiological studies suggest an important role for environmental factors in developing multiple sclerosis (MS). Furthermore several studies have indicated that the effect of environmental factors may be especially pronounced in adolescents. Recently only one study investigated and found that shift work at young age is associated with an increased risk of developing MS. In this study we focused on the effect of shift work in the vulnerable period between 15-19 years.

OBJECTIVE

The aim of this study was to investigate the association between shift work at young age and the risk of developing MS.

METHODS

We performed a large case-control study including 1723 patients diagnosed with MS and 4067 controls. MS patients were recruited from the Danish Multiple Sclerosis Biobank and controls from The Danish Blood Donor Study. Information on working patterns and lifestyle factors was obtained using a comprehensive lifestyle-environmental factor questionnaire with participants enrolled between 2009 and 2014. Logistic regression models were used to investigate the association between shift work at age 15-19 years and the subsequent risk of MS and were controlled for effects due to established MS risk factors.

RESULTS

We found a statistically significant association when total numbers of night shifts were compared with non-shift workers. For every additional 100 night shifts the odds ratio (OR) for MS was 1.20 (95% confidence interval (CI), 1.08-1.34, p=0.001). Increasing intensity of shift work also increased MS risk. For every additional night per month the OR was 1.04 (95% CI, 1.01-1.06, p=0.002). Duration of shift work in years was not associated with risk of MS.

CONCLUSION

This study supports a statistically significant association between shift work at age 15-19 years and MS risk.

Factors influencing success of clinical genome sequencing across a broad spectrum of disorders

To assess factors influencing the success of whole-genome sequencing for mainstream clinical diagnosis, we sequenced 217 individuals from 156 independent cases or families across a broad spectrum of disorders in whom previous screening had identified no pathogenic variants. We quantified the number of candidate variants identified using different strategies for variant calling, filtering, annotation and prioritization. We found that jointly calling variants across samples, filtering against both local and external databases, deploying multiple annotation tools and using familial transmission above biological plausibility contributed to accuracy. Overall, we identified disease-causing variants in 21% of cases, with the proportion increasing to 34% (23/68) for mendelian disorders and 57% (8/14) in family trios. We also discovered 32 potentially clinically actionable variants in 18 genes unrelated to the referral disorder, although only 4 were ultimately considered reportable. Our results demonstrate the value of genome sequencing for routine clinical diagnosis but also highlight many outstanding challenges.

Short-term, high-dose glucocorticoid treatment does not contribute to reduced bone mineral density in patients with multiple sclerosis

Background:

Patients with multiple sclerosis (MS) are at increased risk of reduced bone mineral density (BMD). A contributing factor might be treatment with high-dose glucocorticoids (GCs).

Objectives:

The objective of this paper is to assess bone mass in patients with MS and evaluate the importance of short-term, high-dose GC treatment and other risk factors that affect BMD in patients with MS.

Methods:

A total of 260 patients with MS received short-term high-dose GC treatment and had their BMD measured by dual x-ray absorptiometry. BMD was compared to a healthy age-matched reference population ( Z-scores). Data regarding GCs, age, body mass index (BMI), serum 25(OH)D, disease duration and severity were collected retrospectively and analysed in a multiple linear regression analysis to evaluate the association between each risk factor and BMD.

Results:

Osteopenia was present in 38% and osteoporosis in 7% of the study population. Mean Z-score was significantly below zero, indicating a decreased BMD in our MS patients. Multiple linear regression analysis showed no significant association between GCs and BMD. In contrast, age, BMI and disease severity were independently associated with both lumbar and femoral BMD.

Conclusion:

Reduced BMD was prevalent in patients with MS. GC treatment appears not to be the primary underlying cause of secondary osteoporosis in MS patients.

Genetic variants are major determinants of CSF antibody levels in multiple sclerosis

Immunological hallmarks of multiple sclerosis include the production of antibodies in the central nervous system, expressed as presence of oligoclonal bands and/or an increased immunoglobulin G index-the level of immunoglobulin G in the cerebrospinal fluid compared to serum. However, the underlying differences between oligoclonal band-positive and -negative patients with multiple sclerosis and reasons for variability in immunoglobulin G index are not known. To identify genetic factors influencing the variation in the antibody levels in the cerebrospinal fluid in multiple sclerosis, we have performed a genome-wide association screen in patients collected from nine countries for two traits, presence or absence of oligoclonal bands (n = 3026) and immunoglobulin G index levels (n = 938), followed by a replication in 3891 additional patients. We replicate previously suggested association signals for oligoclonal band status in the major histocompatibility complex region for the rs9271640*A-rs6457617*G haplotype, correlated with HLA-DRB1*1501, and rs34083746*G, correlated with HLA-DQA1*0301 (P comparing two haplotypes = 8.88 × 10(-16)). Furthermore, we identify a novel association signal of rs9807334, near the ELAC1/SMAD4 genes, for oligoclonal band status (P = 8.45 × 10(-7)). The previously reported association of the immunoglobulin heavy chain locus with immunoglobulin G index reaches strong evidence for association in this data set (P = 3.79 × 10(-37)). We identify two novel associations in the major histocompatibility complex region with immunoglobulin G index: the rs9271640*A-rs6457617*G haplotype (P = 1.59 × 10(-22)), shared with oligoclonal band status, and an additional independent effect of rs6457617*G (P = 3.68 × 10(-6)). Variants identified in this study account for up to 2-fold differences in the odds of being oligoclonal band positive and 7.75% of the variation in immunoglobulin G index. Both traits are associated with clinical features of disease such as female gender, age at onset and severity. This is the largest study population so far investigated for the genetic influence on antibody levels in the cerebrospinal fluid in multiple sclerosis, including 6950 patients. We confirm that genetic factors underlie these antibody levels and identify both the major histocompatibility complex and immunoglobulin heavy chain region as major determinants.

Genetic polymorphisms of dsRNA ligating pattern recognition receptors TLR3, MDA5, and RIG-I. Association with systemic lupus erythematosus and clinical phenotypes

This study aimed to demonstrate possible associations between genetic polymorphisms in Toll-like receptor 3, interferon induced with helicase C domain 1 (IFIH1) and DEAD (Asp-Glu-Ala-Asp) box polypeptide 58 and systemic lupus erythematosus (SLE), including the phenotypes lupus nephritis and malar rash, as well as the presence of autoantibodies against nucleic acid-containing complexes. Genotyping was carried out in two Danish cohorts [Copenhagen (CPH) and Odense (ODE)] totaling 344 patients and was compared with 641 previously genotyped healthy controls. In the ODE cohort, the patients were only genotyped for the rs1990760 polymorphism of IFIH1. Single nucleotide polymorphisms (SNPs) were determined by a multiplex bead-based assay (CPH cohort) or real-time PCR (ODE cohort). Associations were investigated using the Cochran-Armitage trend test. The odds ratio (OR) for minor allele homozygotes versus major allele homozygotes suggested a protective effect of the IFIH1 rs1990760 SNP for SLE in the ODE cohort [OR 0.52, 95 % confidence intervals (95 % CI) 0.31-0.88, Pcorr. = 0.05] but not in the CPH cohort, although the OR suggested a trend in the same direction, and when combining the two patient cohorts, ORs were 0.57, 95 % CI 0.37-0.88. None of the other investigated polymorphisms showed any association with SLE. Regarding phenotypes, we found a statistically significant association between rs1990760 and malar rash in the CPH cohort, with ORs suggesting a protective effect (OR 0.28, 95 % CI 0.13-0.62 for heterozygotes and OR 0.11, 95 % CI 0.03-0.41 for homozygotes, Pcorr. = 0.0001). There were no significant associations between rs1990760 and presence of anti-dsDNA, anti-U1RNP, or anti-Smith antibodies. Our study supports previous findings of an association between the rs1990760 polymorphism of IFIH1 and SLE and indicates that this SNP may also be associated with malar rash in SLE patients although this finding needs confirmation.

Oligoclonal band status in Scandinavian multiple sclerosis patients is associated with specific genetic risk alleles

The presence of oligoclonal bands (OCB) in cerebrospinal fluid (CSF) is a typical finding in multiple sclerosis (MS). We applied data from Norwegian, Swedish and Danish (i.e. Scandinavian) MS patients from a genome-wide association study (GWAS) to search for genetic differences in MS relating to OCB status. GWAS data was compared in 1367 OCB positive and 161 OCB negative Scandinavian MS patients, and nine of the most associated SNPs were genotyped for replication in 3403 Scandinavian MS patients. HLA-DRB1 genotypes were analyzed in a subset of the OCB positive (n = 2781) and OCB negative (n = 292) MS patients and compared to 890 healthy controls. Results from the genome-wide analyses showed that single nucleotide polymorphisms (SNPs) from the HLA complex and six other loci were associated to OCB status. In SNPs selected for replication, combined analyses showed genome-wide significant association for two SNPs in the HLA complex; rs3129871 (p = 5.7×10(-15)) and rs3817963 (p = 5.7×10(-10)) correlating with the HLA-DRB1*15 and the HLA-DRB1*04 alleles, respectively. We also found suggestive association to one SNP in the Calsyntenin-2 gene (p = 8.83×10(-7)). In HLA-DRB1 analyses HLA-DRB1*15∶01 was a stronger risk factor for OCB positive than OCB negative MS, whereas HLA-DRB1*04∶04 was associated with increased risk of OCB negative MS and reduced risk of OCB positive MS. Protective effects of HLA-DRB1*01∶01 and HLA-DRB1*07∶01 were detected in both groups. The groups were different with regard to age at onset (AAO), MS outcome measures and gender. This study confirms both shared and distinct genetic risk for MS subtypes in the Scandinavian population defined by OCB status and indicates different clinical characteristics between the groups. This suggests differences in disease mechanisms between OCB negative and OCB positive MS with implications for patient management, which need to be further studied.

Effect of natalizumab on circulating CD4+ T-cells in multiple sclerosis

In multiple sclerosis (MS), treatment with the monoclonal antibody natalizumab effectively reduces the formation of acute lesions in the central nervous system (CNS). Natalizumab binds the integrin very late antigen (VLA)-4, expressed on the surface of immune cells, and inhibits VLA-4 dependent transmigration of circulating immune-cells across the vascular endothelium into the CNS. Recent studies suggested that natalizumab treated MS patients have an increased T-cell pool in the blood compartment which may be selectively enriched in activated T-cells. Proposed causes are sequestration of activated T-cells due to reduced extravasation of activated and pro-inflammatory T-cells or due to induction of VLA-4 mediated co-stimulatory signals by natalizumab. In this study we examined how natalizumab treatment altered the distribution of effector and memory T-cell subsets in the blood compartment and if T-cells in general or myelin-reactive T-cells in particular showed signs of increased immune activation. Furthermore we examined the effects of natalizumab on CD4(+) T-cell responses to myelin in vitro. Natalizumab-treated MS patients had significantly increased numbers of effector-memory T-cells in the blood. In T-cells from natalizumab-treated MS patients, the expression of TNF-α mRNA was increased whereas the expression of fourteen other effector cytokines or transcription factors was unchanged. Natalizumab-treated MS patients had significantly decreased expression of the co-stimulatory molecule CD134 on CD4(+)CD26(HIGH) T-cells, in blood, and natalizumab decreased the expression of CD134 on MBP-reactive CD26(HIGH)CD4(+) T-cells in vitro. Otherwise CD4(+) T-cells from natalizumab-treated and untreated MS patients showed similar responses to MBP. In conclusion natalizumab treatment selectively increased the effector memory T-cell pool but not the activation state of T-cells in the blood compartment. Myelin-reactive T-cells were not selectively increased in natalizumab treated MS.

A genome-wide association study in progressive multiple sclerosis

Background: The role played by genetic factors in influencing the clinical course of multiple sclerosis (MS) is not yet well established.

Objective: We aimed to identify genetic variants associated with progressive MS (PrMS).

Methods: We conducted a genome-wide association study (GWAS) in 197 patients with PrMS and 234 controls of Italian origin. We tested the top 20 single nucleotide polymorphisms (SNPs) with suggestive evidence of association ( p-value<10−4) in two independent sets of primary progressive MS cases and controls.

Results: We identified a risk-associated SNP in the HLA region in linkage disequilibrium (LD) with DRB1*1501 and DQB*0602 loci, with genome-wide significance (rs3129934T, pcombined=6.7×10-16, OR=2.34, 95% CI=1.90–2.87), and a novel locus on chromosome 7q35 with suggestive evidence of association (rs996343G, pcombined=2.4×10-5, OR=0.70, 95% CI=0.59–0.83) which maps within a human endogenous retroviral (HERV) element. The new locus did not have a ‘ cis’ effect on RNA expression in lymphoblastic cell lines, but pathway analyses of ‘ trans’ effects point to an expression regulation of genes involved in neurodegeneration, including glutamate metabolism ( p<0.01) and axonal guidance signalling ( p<0.02).

Conclusions: We have confirmed the established association with the HLA region and, despite the low statistical power of the study, we found suggestive evidence for association with a novel locus on chromosome 7, with a putative regulatory role.

RGMA and IL21R show association with experimental inflammation and multiple sclerosis

Rat chromosome 1 harbors overlapping quantitative trait loci (QTL) for cytokine production and experimental models of inflammatory diseases. We fine-dissected this region that regulated cytokine production, myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis (EAE), anti-MOG antibodies and pristane-induced arthritis (PIA) in advanced intercross lines (AILs). Analysis in the tenth and twelfth generation of AILs resolved the region in two narrow QTL, Eae30 and Eae31. Eae30 showed linkage to MOG-EAE, anti-MOG antibodies and levels of interleukin-6 (IL-6). Eae31 showed linkage to EAE, PIA, anti-MOG antibodies and levels of tumor necrosis factor (TNF) and IL-6. Confidence intervals defined a limited set of potential candidate genes, with the most interesting being RGMA, IL21R and IL4R. We tested the association with multiple sclerosis (MS) in a Nordic case-control material. A single nucleotide polymorphism in RGMA associated with MS in males (odds ratio (OR)=1.33). Polymorphisms of RGMA also correlated with changes in the expression of interferon-gamma (IFN-gamma) and TNF in cerebrospinal fluid of MS patients. In IL21R, there was one positively associated (OR=1.14) and two protective (OR=0.87 and 0.68) haplotypes. One of the protective haplotypes correlated to lower IFN-gamma expression in peripheral blood mononuclear cells of MS patients. We conclude that RGMA and IL21R and their pathways are crucial in MS pathogenesis and warrant further studies as potential biomarkers and therapeutic targets.

Multiple sclerosis and polymorphisms of innate pattern recognition receptors TLR1-10, NOD1-2, DDX58, and IFIH1

Genetic factors are critical in multiple sclerosis (MS), and it is conceivable that the pattern recognition receptors of the innate immune system are of pathogenic importance. We therefore developed two novel assays capable of analyzing 42 single-nucleotide polymorphisms in the human genes encoding TLR1-10, NOD1-2, DDX58, and IFIH1. Using these assays, we genotyped 963 MS patients and 960 controls, and analyzed for possible associations to MS diagnosis, clinical course, severity, and age at onset. Our results support previous findings of associations between the IFIH1-locus and MS (IFIH1-rs3747517 and IFIH1-rs1990760 trend test: P=0.002 and P=0.014, respectively).

Concordance for disease course and age of onset in Scandinavian multiple sclerosis coaffected sib pairs

BACKGROUND

Investigation of coaffected sib pairs is one method to determine the genetic influence on the clinical presentation of many complex diseases, such as multiple sclerosis (MS). Investigation of the clinical concordance in coaffected sib pairs may be a prerequisite to identify genes that modify the clinical outcome. The aim of this study was to investigate a possible genetic influence on selected demographic and clinical variables among familial Scandinavian MS cases.

MATERIAL AND METHODS

We identified 136 Caucasian Scandinavian families with MS coaffected sib pairs from Denmark, Norway and Sweden. Cohen's kappa coefficient and the intraclass correlation coefficient were used to assess concordances in sib pairs. Furthermore, clinical features and HLA-DR2 carrier status were compared among the probands of sib pairs.

RESULTS

We found significant concordance of the disease course (kappa = 0.28, P < 0.001) and adjusted age of onset (r = 0.23, P = 0.028). Among probands of sib pairs, HLA-DR2 carrier patients had a younger age of onset (P = 0.024).

CONCLUSION

Analyses of Scandinavian coaffected sib pairs suggest that disease course and age of onset are partly under genetic control. Furthermore, HLA-DR2 in probands of sib pairs suggests importance for age of onset.

[Neurosurgical treatment of trigeminal neuralgia. A comparative study of alcohol block, neurectomy and electrocoagulation]

The objective was to assess the present condition of patients previously treated with neurosurgical procedures for trigeminal neuralgia (TN). Between 1976 and 1991, 383 patients were treated for TN at the Department of Neurosurgery, Hvidovre Hospital. The latest surgical intervention performed was radiofrequency coagulation (64%), neurectomy (18%), alcohol block (16%), trigeminal tractotomy (1%), and microvascular decompression (1%). Questionnaires were sent to 316 patients treated neurosurgically for trigeminal neuralgia during the 16 year period. After radiofrequency coagulation, neurectomy and alcohol block, 83, 51 and 42% respectively experienced a pain free postoperative period. At present 49, 17 and 18% were without pain and 33, 21 and 36% had less pain compared with the preoperative state. Sequelae were described in 65, 57 and 49% of the patients. The four most common sequelae were hypaesthesia, paraesthesia, eye complaints, and dysaesthesia. If relevant pharmacotherapy has been tried without benefit, radiofrequency coagulation may still be considered as a treatment of trigeminal neuralgia.

Neurosurgery for trigeminal neuralgia: comparison of alcohol block, neurectomy, and radiofrequency coagulation

OBJECTIVES

We wished to assess the present condition of patients previously treated with a neurosurgical procedure or procedures for trigeminal neuralgia (TN) in 383 patients treated between 1976 and 1991, for TN at the Department of Neurosurgery, Hvidovre Hospital. Of these, 67 were lost to follow-up. The latest surgical intervention performed was radiofrequency coagulation (RFC) (64%), neurectomy (18%), alcohol block (16%), trigeminal tractotomy (1%), and microvascular decompression (1%); 72% of patients underwent only one neurosurgical procedure.

METHODS

Questionnaires were sent to 316 patients treated neurosurgically for TN during the 16-year period; 288 (91%) patients responded. The follow-up period varied from 1 to 16 years (mean 8 years). Outcome measures were effect of RFC, neurectomy, and alcohol block; present pain conditions; and sequelae.

RESULTS

After RFC, neurectomy, and alcohol block, 83, 51, and 42% of patients, respectively, experienced a pain-free postoperative period; 49, 78, and 84% of these patients had recurrence of pain. At present, 49, 17, and 18% are pain-free and 33, 21, and 36% now have less pain than they did preoperatively. Temporary or permanent analgesics for facial pain were required in 41, 72, and 69% of the patients. Sequelae were described by 65, 57, and 49% of the patients. The four most common sequelae were hypoesthesia, paresthesia, eye complaints, and dysesthesia.

CONCLUSION

If relevant pharmacotherapy has been tried without benefit, RFC may still be considered as a treatment for TN.