HLA-DR 15 is associated with female sex and younger age at diagnosis in multiple sclerosis

Immunopathogenesis of multiple sclerosis: molecular and cellular mechanisms and new immunotherapeutic approaches

BACKGROUND

Multiple sclerosis (MS) is a central nervous system (CNS) demyelinating autoimmune disease with increasing global prevalence. It predominantly affects females, especially those of European descent. The interplay between environmental factors and genetic predisposition plays a crucial role in MS etiopathogenesis.

METHODS

We searched recent relevant literature on reputable databases, which include, PubMed, Embase, Web of Science, Scopus, and ScienceDirect using the following keywords: multiple sclerosis, pathogenesis, autoimmunity, demyelination, therapy, and immunotherapy.

RESULTS

Various animal models have been employed to investigate the MS etiopathogenesis and therapeutics. Autoreactive T cells within the CNS recruit myeloid cells through chemokine expression, leading to the secretion of inflammatory cytokines driving the MS pathogenesis, resulting in demyelination, gliosis, and axonal loss. Key players include T cell lymphocytes (CD4+ and CD8+), B cells, and neutrophils. Signaling dysregulation in inflammatory pathways and the immunogenetic basis of MS are essential considerations for any successful therapy to MS. Data indicates that B cells and neutrophils also have significant roles in MS, despite the common belief that T cells are essential. High neutrophil-to-lymphocyte ratios correlate with MS severity, indicating their contribution to disease progression. Dysregulated signaling pathways further exacerbate MS progression.

CONCLUSION

MS remains incurable, but disease-modifying therapies, monoclonal antibodies, and immunomodulatory drugs offer hope for patients. Research on the immunogenetics and immunoregulatory functions of gut microbiota is continuing to provide light on possible treatment avenues. Understanding the complex interplay between genetic predisposition, environmental factors, and immune dysregulation is critical for developing effective treatments for MS.

Major histocompatibility complex (MHC) gene frequency in acquired dermal macular hyperpigmentation: a case control study

BACKGROUND

Human leukocyte antigen (HLA) allele frequencies have a known association with the pathogenesis of various autoimmune diseases.

METHODS

We recruited 31 Indian patients of acquired dermal macular hyperpigmentation (ADMH) and 60 unrelated, age-and-gender-matched healthy controls. After history and clinical examination, 5 ml of blood in EDTA vials was collected. These samples were subjected to DNA extraction and the expression of HLA A, B, C, DR, DQ-A, and DQ-B was studied.

RESULTS

There was a predominance of females with a gender ratio of 23 : 8 and the most common phototype was Fitzpatrick type IV (83.9%). There was a significant association of HLA A*03:01 (OR: 5.8, CI: 1.7-17.0, P = 0.005), HLA B*07:02 (OR: 5.3, CI: 1.9-14.6, P = 0.003), HLA C*07:02 (OR: 4.3, CI: 1.8-9.6, P = 0.001), HLA DRB1*10:01 (OR: 7.6, CI: 1.7-38.00, P = 0.022), and HLA DRB1*15:02 (OR: 31.0, CI: 4.4-341.8, P < 0.001) with patients compared to controls, whereas HLA DQB*03:01 was less associated with patients compared to controls (OR: 0.2, CI: 0.0-0.6, P = 0.009).

CONCLUSION

Patients with ADMH are more likely to have the HLA A*03:01, HLA B 07*02, HLA C*07:02, HLA DRB1*10:01, HLA DRB1*15:02 and less likely to have the HLA DQB*03:01 allele. Larger cohort studies may thus be conducted studying these specific alleles.

The impact of HLA-DRB1 alleles in a Hellenic, Pediatric-Onset Multiple Sclerosis cohort: Implications on clinical and neuroimaging profile

BACKGROUND

Pediatric-Onset Multiple Sclerosis (POMS) is considered a complex disease entity and several genetic, hormonal, and environmental factors have been associated with disease pathogenesis. Linkage studies in Caucasians have consistently suggested the human leukocyte antigen (HLA) polymorphisms, as the genetic locus most strongly linked to MS, with the HLA-DRB1*15:01 allele, being associated with both adult and pediatric MS patients. Here we aim to investigate the prevalence of the HLA-DRB1 alleles among a Hellenic POMS cohort and any possible associations with clinical and imaging disease features.

MATERIALS AND METHODS

100 POMS patients fulfilling the IPMSSG criteria, 168 Adult-Onset MS (AOMS) patients, and 246 Healthy Controls (HCs) have been enrolled. HLA genotyping was performed with a standard low-resolution sequence-specific oligonucleotide (SSO) technique.

RESULTS

POMS patients display a significantly increased HLA-DRB1*03 frequency compared to both HCs [24% vs. 12.6%, OR [95%CI]: 2.19 (1.21-3.97), p=0.016) and AOMS (24% vs. 13.1%, OR [95%CI]: 2.1 (1.1-3.98), p=0.034] respectively. HLA-DRB1*03-carriers display reduced risk for brainstem lesion development (OR [CI 95%]:0.19 (0.06-0.65), p=0.011). A significantly lower frequency of HLA-DRB1*07 (4% vs 13.4%, OR (95% CI): 0.27 (0.09-0.78), p= 0.017) and HLA-DRB1*11 (37% vs 52%, OR [95% CI]: 0.54 (0.34-0.87), p= 0.016) was observed in POMS compared to HCs.

CONCLUSION

The HLA-DRB1*03 allele was associated with a higher risk for POMS, replicating our previous findings, and with a lower risk for brainstem lesion development, a common clinical and neuroimaging feature in POMS, while HLA-DRB1*07 and HLA-DRB1*11 display a protective role. These findings expand the existing knowledge of HLA associations and POMS.

HLA-DRB1*1501 influences long-term disability progression and tissue damage on MRI in relapse-onset multiple sclerosis

BACKGROUND

Whether genetic factors influence the long-term course of multiple sclerosis (MS) is unresolved.

OBJECTIVE

To determine the influence of HLA-DRB1*1501 on long-term disease course in a homogeneous cohort of clinically isolated syndrome (CIS) patients.

METHODS

One hundred seven patients underwent clinical and MRI assessment at the time of CIS and after 1, 3, 5 and 15 years. HLA-DRB1*1501 status was determined using Sanger sequencing and tagging of the rs3135388 polymorphism. Linear/Poisson mixed-effects models were used to investigate rates of change in EDSS and MRI measures based on HLA-DRB1*1501 status.

RESULTS

HLA-DRB1*1501 -positive (n = 52) patients showed a faster rate of disability worsening compared with the HLA-DRB1*1501 -negative (n = 55) patients (annualised change in EDSS 0.14/year vs. 0.08/year, p < 0.025), and a greater annualised change in T2 lesion volume (adjusted difference 0.45 mL/year, p < 0.025), a higher number of gadolinium-enhancing lesions, and a faster rate of brain (adjusted difference -0.12%/year, p < 0.05) and spinal cord atrophy (adjusted difference -0.22 mm²/year, p < 0.05).

INTERPRETATION

These findings provide evidence that the HLA-DRB1*1501 allele plays a role in MS severity, as measured by long-term disability worsening and a greater extent of inflammatory disease activity and tissue loss. HLA-DRB1*1501 may provide useful information when considering prognosis and treatment decisions in early relapse-onset MS.

Ancestral risk modification for multiple sclerosis susceptibility detected across the Major Histocompatibility Complex in a multi-ethnic population

The Major Histocompatibility Complex (MHC) makes the largest genetic contribution to multiple sclerosis (MS) susceptibility, with 32 independent effects across the region explaining 20% of the heritability in European populations. Variation is high across populations with allele frequency differences and population-specific risk alleles identified. We sought to identify MHC-specific MS susceptibility variants and assess the effect of ancestral risk modification within 2652 Latinx and Hispanic individuals as well as 2435 Black and African American individuals. We have identified several novel susceptibility alleles which are rare in European populations including HLA-B*53:01, and we have utilized the differing linkage disequilibrium patterns inherent to these populations to identify an independent role for HLA-DRB1*15:01 and HLA-DQB1*06:02 on MS risk. We found a decrease in Native American ancestry in MS cases vs controls across the MHC, peaking near the previously identified MICB locus with a decrease of ~5.5% in Hispanics and ~0.4% in African Americans. We have identified several susceptibility variants, including within the MICB gene region, which show global ancestry risk modification and indicate ancestral differences which may be due in part to correlated environmental factors. We have also identified several susceptibility variants for which MS risk is modified by local ancestry and indicate true ancestral genetic differences; including HLA-DQB1*06:02 for which MS risk for European allele carriers is almost two times the risk for African allele carriers. These results validate the importance of investigating MS susceptibility at an ancestral level and offer insight into the epidemiology of MS phenotypic diversity.

Clinical and Genetic Analysis in Pediatric Patients with Multiple Sclerosis and Related Conditions: Focus on DR Genes of the Major Histocompatibility Complex

Introduction:

There are several diseases recognized as variants of MS: post-infectious acute disseminated encephalitis, multiple sclerosis (MS), Rasmussen leukoencephalitis and Schilder's leukoencephalitis and related, but separate neuroimmune condition – Neuromyelitis Devic’s. In Kazakhstan diagnosis of such diseases was rare and immune modified treatment was only admitted after the age of 18. Clinical and immunogenetic study of MS spectrum diseases in Kazakhstan would allow to justify early targeted treatment.

Objective:

The aim of the study was to investigate genes of the main complex of human histocompatibility (MHC) associated with diseases of MS spectrum in Kazakhstani population.

Methods:

Complex clinical, neuroimaging and immunogenetic studies were performed in 34 children (24 girls, 10 boys) aged 4 to 18 years. 21 children were diagnosed with MS (11 Kazakh origin and 10 – Russian; 4 boys, 17 girls), 7 with leucoencephalitis (all Kazakh, 5 boys, 2 girls) and 6 with Devic neuromyelitis optica (all Kazakh, 1 boy, 5 girls). Genotyping of HLA DRB1, DQA1, DQB1 genes was performed for all patients.

Results:

MS group was characterized by classical relapsing-remitting MS. Predominant haplotype as a linkage complex was DRB1*15:01~DQA1*01:02~DQB1*06:02 in 20 (47.6%) of 42 DR-alleles, in 16 (76.2%) patients. MS relative risk (RR) was 13,36 for ethnic Kazakhs and RR=5,55 in Russians.

Leukoencephalitis had 7 children, with 28.6% mortality rate. The haplotype DRB1*15:01~DQA1*01:02~DQB1*06:02 as a linkage complex was detected 3 patients (4 alleles), RR=5,88.

Devic’s neuromyelitis optica (NMO) clinical course was characterized by fast and prolonged progression. There was predominance of DRB1*14 allele with RR=3,38.

Conclusion:

Summarizing, in the Kazakh population the haplotype DRB1*15:01∼DQA1*01:02∼DQB1*06:02 as a linkage complex was associated with prediction to MS and leukoencephalitis, but not to Devic’s NMO. Our study highlights the importance of awareness of MS and related disorders diagnosis which allows to implement early admission of disease-modified treatment in pediatric MS in Kazakhstan.

The gut microbiome molecular mimicry piece in the multiple sclerosis puzzle

The etiological complexity of multiple sclerosis, an immune-mediated, neurodegenerative disease with multifactorial etiology is still elusive because of an incomplete understanding of the complex synergy between contributing factors such as genetic susceptibility and aberrant immune response. Recently, the disease phenotypes have also been shown to be associated with dysbiosis of the gut microbiome, a dynamic reservoir of billions of microbes, their proteins and metabolites capable of mimicring the autoantigens. Microbial factors could potentially trigger the neuroinflammation and symptoms of MS. In this perspective article, we discussed how microbial molecules resulting from a leaky gut might mimic a host’s autoantigen, potentially contributing to the disease disequilibrium. It further highlights the importance of targeting the gut microbiome for alternate therapeutic options for the treatment of MS.

High-resolution HLA class II sequencing of Swedish multiple sclerosis patients

Multiple sclerosis (MS) is a chronic neurological disease believed to be caused by autoimmune pathogenesis. The aetiology is likely explained by a complex interplay between inherited and environmental factors. Genetic investigations into MS have been conducted for over 50 years, yielding >100 associations to date. Globally, the strongest linkage is with the human leukocyte antigen (HLA) HLA-DRB5*01:01:01-DRB1*15:01:01-DQA1*01:02:01-DQB1*06:02:01 haplotype. Here, high-resolution sequencing of HLA was used to determine the alleles of DRB3, DRB4, DRB5, DRB1, DQA1, DQB1, DPA1 and DPB1 as well as their extended haplotypes and genotypes in 100 Swedish MS patients. Results were compared to 636 population controls. The heterogeneity in HLA associations with MS was demonstrated; among 100 patients, 69 extended HLA-DR-DQ genotypes were found. Three extended HLA-DR-DQ genotypes were found to be correlated to MS; HLA-DRB5*01:01:01-DRB1*15:01:01-DQA1*01:02:01-DQB1*06:02:01 haplotype together with (A) HLA-DRB4*01:01:01//DRB4*01:01:01:01-DRB1*07:01:01-DQA1*02:01//02:01:01-DQB1*02:02:01, (B) HLA-DRBX*null-DRB1*08:01:01-DQA1*04:01:01-DQB1*04:02:01, and (C) HLA-DRB3*01:01:02-DRB1*03:01:01-DQA1*05:01:01-DQB1*02:01:01. At the allelic level, HLA-DRB3*01:01:02 was considered protective against MS. However, when combined with HLA-DRB3*01:01:02-DRB1*03:01:01-DQA1*05:01:01-DQB1*02:01:01, this extended haplotype was considered a predisposing risk factor. This highlights the limitations as included with investigations of single alleles relative to those of extended haplotypes/genotypes. In conclusion, with 69 genotypes presented among 100 patients, high-resolution sequencing was conducted to underscore the wide polymorphisms present among MS patients. Additional studies in larger cohorts will be of importance to define MS among the patient group not associated with HLA-DRB5*01:01:01-DRB1*15:01:01-DQA1*01:02:01-DQB1*06:02:01.

HLA-DRB1*03:01 is associated with female sex and younger age of anti-LGI1 encephalitis

OBJECTIVE

To investigate the association between human leukocyte antigen (HLA) genotype and clinical characteristics of anti-LGI1 encephalitis.

METHODS

HLA genotyping was performed in 34 patients with anti-LGI1 encephalitis admitted to West China Hospital between April 2014 and May 2021, as well as in 305 healthy controls. The on-line tool NetMHCIIpan 4.0 and AutoDock Vina software were used to predict binding between LGI1 peptide and HLA Class II molecules.

RESULTS

Risk of anti-LGI1 encephalitis was strongly associated with the DRB1*03:01 allele (OR 4.31, 95% CI 1.96-9.25, Pc = 2.75×10^-4 ) and the DRB1*03:01-DQB1*02:01 haplotype (OR 4.45, 95% CI 2.02-9.59, Pc = 2.94×10^-4 ). Compared to carriers of the DRB1*07:01 allele, those with the DRB1*03:01 allele were more likely to be female (93.3% vs 33.3%; P = 0.004) and to be younger (median age, 38 vs 65 years; P < 0.001). DRB1*03:01 carriers showed stronger response to immunotherapy than carriers of the DRB1*07:01 allele, based on median score decrease on the modified Rankin scale [2 (interquartile range, 1-2) vs. 1 (interquartile range, 0-1); P = 0.03] at 4 weeks after immunotherapy. Prediction and docking algorithms suggested that the LGI1 peptide can bind to the DRB1*03:01 molecule strongly.

CONCLUSIONS

The strong association between anti-LGI1 encephalitis and certain HLA class II alleles supports a primary autoimmune origin for the disease. Carriers of the DRB1*03:01 allele in Chinese patients with anti-LGI1 encephalitis are more likely to be female, to suffer earlier disease onset and to respond better to immunotherapy.

Immune Cell Contributors to the Female Sex Bias in Multiple Sclerosis and Experimental Autoimmune Encephalomyelitis

Multiple sclerosis (MS) is a chronic, autoimmune, demyelinating disease of the central nervous system (CNS) that leads to axonal damage and accumulation of disability. Relapsing-remitting MS (RR-MS) is the most frequent presentation of MS and this form of MS is three times more prevalent in females than in males. This female bias in MS is apparent only after puberty, suggesting a role for sex hormones in this regulation; however, very little is known of the biological mechanisms that underpin the sex difference in MS onset. Experimental autoimmune encephalomyelitis (EAE) is an animal model of RR-MS that presents more severely in females in certain mouse strains and thus has been useful to study sex differences in CNS autoimmunity. Here, we overview the immunopathogenesis of MS and EAE and how immune mechanisms in these diseases differ between a male and female. We further describe how females exhibit more robust myelin-specific T helper (Th) 1 immunity in MS and EAE and how this sex bias in Th cells is conveyed by sex hormone effects on the T cells, antigen presenting cells, regulatory T cells, and innate lymphoid cell populations.

Clinical and Prognostic Value of Immunogenetic Characteristics in Anti-LGI1 Encephalitis

Objective

Antibodies against leucine-rich glioma-inactivated 1 (LGI1-Abs) characterize a limbic encephalitis (LE) strongly associated with HLA-DRB1*07:01, although some patients lack LGI1-Abs in CSF or do not carry this allele. Whether they represent a different subtype of disease or have different prognoses is unclear.

Methods

Retrospective analysis of clinical features, IgG isotypes, and outcome according to LGI1-Ab CSF positivity and DRB1*07:01 in a cohort of anti-LGI1 LE patients.

Results

Patients with LGI1-Abs detected in both CSF and serum (105/134, 78%) were compared with those who were CSF negative (29/134, 22%). Both groups had similar clinical features and serum levels, but CSF-positive patients had shorter diagnostic delay, more frequently hyponatremia, inflammatory CSF, and abnormal MRI (p < 0.05). Human leukocyte antigen (HLA) genotyping was performed in 72/134 (54%) patients and 63/72 (88%) carried DRB1*07:01. Noncarriers (9/72, 12%) were younger, more commonly women, and had less frequently psychiatric and frontal symptoms (p < 0.05). No difference in IgG isotypes according to CSF positivity or HLA was found (p > 0.05). HLA and IgG isotypes were not associated with poor outcome (mRS >2 at last follow-up) in univariate analyses; CSF positivity was only identified as a poor outcome predictor in the multivariate analysis including the complete follow-up, whereas age and female sex also remained when just the first year was considered.

Conclusions

LE without CSF LGI1-Abs is clinically indistinguishable and likely reflects just a lesser LGI1-Ab production. HLA association is sex and age biased and presents clinical particularities, suggesting subtle differences in the immune response. Long-term outcome depends mostly on demographic characteristics and the intensity of the intrathecal synthesis.

HLA-DRB1 allele impact on pediatric multiple sclerosis in a Hellenic cohort

Background

Pediatric-onset multiple sclerosis (POMS) is considered a complex disease entity with many genetic and environmental factors implicated in its pathogenesis. Linkage studies in Caucasian adult populations consistently demonstrate the major histocompatibility complex and its HLA (human leukocyte antigen) polymorphisms as the genetic locus most strongly linked to MS.

Objective

To investigate the frequencies and possible clinical and imaging correlations of HLA-DRB1 alleles in a Hellenic POMS sample.

Methods

Fifty POMS patients fulfilling the IPMSSG (International Pediatric Multiple Sclerosis Study Group) criteria were enrolled using 144 adult-onset MS (AOMS) patients and 246 healthy controls for comparisons. HLA genotyping was performed with standard low-resolution sequence-specific oligonucleotide (SSO) techniques. Clinical and imaging correlations with specific HLA-DRB1 alleles were also examined.

Results

The HLA-DRB1*03 genotype was significantly higher in POMS patients compared to both the AOMS population (26% vs. 12.5%, p = 0.042) and the general population (26% vs. 12.6%, p = 0.004). HLA-DRB1*03-positive POMS patients had significantly more relapses (6.9 ± 4.9 vs. 4.2 ± 4.4, p = 0.005) and more thoracic spinal cord lesions than HLA-DRB1*03-negative patients (61.5% vs. 27%, p = 0.043).

Conclusion

In our Hellenic population, HLA-DRB1*03 allele confers increased risk for POMS and it is also correlated with possibly increased disease activity, expanding the existing knowledge on HLA associations and POMS.

Recent advances in understanding multiple sclerosis

Emerging data point to important contributions of both autoimmune inflammation and progressive degeneration in the pathophysiology of multiple sclerosis (MS). Unfortunately, after decades of intensive investigation, the fundamental cause remains unknown. A large body of research on the immunobiology of MS has resulted in a variety of anti-inflammatory therapies that are highly effective at reducing brain inflammation and clinical/radiological relapses. However, despite potent suppression of inflammation, benefit in the more important and disabling progressive phase is extremely limited; thus, progressive MS has emerged as the greatest challenge for the MS research and clinical communities. Data obtained over the years point to a complex interplay between environment (e.g., the near-absolute requirement of Epstein-Barr virus exposure), immunogenetics (strong associations with a large number of immune genes), and an ever more convincing role of an underlying degenerative process resulting in demyelination (in both white and grey matter regions), axonal and neuro-synaptic injury, and a persistent innate inflammatory response with a seemingly diminishing role of T cell-mediated autoimmunity as the disease progresses. Together, these observations point toward a primary degenerative process, one whose cause remains unknown but one that entrains a nearly ubiquitous secondary autoimmune response, as a likely sequence of events underpinning this disease. Here, we briefly review what is known about the potential pathophysiological mechanisms, focus on progressive MS, and discuss the two main hypotheses of MS pathogenesis that are the topic of vigorous debate in the field: whether primary autoimmunity or degeneration lies at the foundation. Unravelling this controversy will be critically important for developing effective new therapies for the most disabling later phases of this disease.

Human Leukocyte Antigen Genotype as a Marker of Multiple Sclerosis Prognosis

OBJECTIVE

In a previous pilot monocentric study, we investigated the relation between human leukocyte antigen (HLA) genotype and multiple sclerosis (MS) disease progression over 2 years. HLA-A*02 allele was correlated with better outcomes, whereas HLA-B*07 and HLA-B*44 were correlated with worse outcomes. The objective of this extension study was to further investigate the possible association of HLA genotype with disease status and progression in MS as measured by sensitive and complex clinical and imaging parameters.

METHODS

Hundred and forty-six MS patients underwent HLA typing. Over a 4-year period of follow-up, we performed three clinical and magnetic resonance imaging (MRI) assessments per patient, which respectively included Expanded Disability Status Scale, Multiple Sclerosis Severity Scale, Timed-25-Foot-Walk, 9-Hole Peg Test, Symbol Digit Modalities Test, Brief Visual Memory Test, California Verbal Learning Test-II, and whole-brain atrophy, fluid-attenuated inversion recovery (FLAIR) lesion volume change and number of new FLAIR lesions using icobrain. We then compared the clinical and MRI outcomes between predefined HLA patient groups.

RESULTS

Results of this larger study with a longer follow-up are in line with what we have previously shown. HLA-A*02 allele is associated with potentially better MS outcomes, whereas HLA-B*07, HLA-B*44, HLA-B*08, and HLA-DQB1*06 with a potential negative effect. Results for HLA-DRB1*15 are inconclusive.

CONCLUSION

In the era of MS treatment abundance, HLA genotype might serve as an early biomarker for MS outcomes to inform individualized treatment decisions.

The Contribution of Major Histocompatibility Complex Class II Genes to an Association with Autoimmune Diseases

Genetic studies of patients with autoimmune diseases have shown that one of the most important roles in the developing of these diseases is played by a cluster of genes of the major histocompatibility complex (MHC), as compared with other genome areas. Information on the specific contribution of MHC alleles, mostly MHC class II ones, to the genetic predisposition to autoimmune diseases is crucial for understanding their pathogenesis. This review dwells on the most relevant aspects of this problem: namely, the correlation between carriage of certain MHC II alleles and an increased (positively associated allele) or reduced (negatively associated allele) probability of developing the most common autoimmune diseases, such as type 1 diabetes, rheumatoid arthritis, multiple sclerosis, systemic lupus erythematosus, autoimmune thyroiditis, etc. The most universal haplotypes, DR3-DQ2 and DR4-DQ8, are positively associated with many of these diseases, while the universal allele HLA-DRB1*0701 is protective.

Genetic and Molecular Biology of Multiple Sclerosis Among Iranian Patients: An Overview

Multiple sclerosis (MS) is one if the common types of autoimmune disorders in developed countries. Various environmental and genetic factors are associated with initiation and progression of MS. It is believed that the life style changes can be one of the main environmental risk factors. The environmental factors are widely studied and reported, whereas minority of reports have considered the role of genetic factors in biology of MS. Although Iran is a low-risk country in the case of MS prevalence, it has been shown that there was a dramatically rising trend of MS prevalence among Iranian population during recent decades. Therefore, it is required to assess the probable MS risk factors in Iran. In the present study, we summarized all of the reported genes until now which have been associated with MS susceptibility among Iranian patients. To clarify the probable molecular biology of MS progression, we categorized these reported genes based on their cellular functions. This review paves the way of introducing a specific population-based diagnostic panel of genetic markers among the Iranian population for the first time in the world.

Familial risk of early- and late-onset multiple sclerosis: a Swedish nationwide study

BACKGROUND

Persons who develop multiple sclerosis (MS) at a young age may bear a higher genetic risk load than persons who develop MS later in life; however, the contribution of familial influence to the risk of MS, in relation to onset age, has not been established.

OBJECTIVE

To investigate the familial risk of MS at two extremes of the spectrum of MS onset age: early onset (first MS symptom < 18 years of age) and late onset (first MS symptom ≥ 50 years).

METHODS

Nationwide registries in Sweden were used to identify cases of MS and controls, and their familial relations. We estimated the odds ratio (OR) of an MS diagnosis for individuals with a relative diagnosed with early-onset or late-onset MS compared with those whose relatives did not have MS, using a nested case-control design.

RESULTS

629 early-onset and 1148 late-onset MS patients were identified and matched to 10 controls from the general population by age and sex. The OR of MS for individuals with a first-degree relative diagnosed with early-onset MS was 10.86 (95% CI 6.87-17.17); and for late-onset MS was 8.08 (95% CI 6.12-10.67).

CONCLUSIONS

Our findings demonstrate no substantial differences in familial risk in persons with early- and late-onset MS.

Anti-Myelin Oligodendrocyte Glycoprotein and Human Leukocyte Antigens as Markers in Pediatric and Adolescent Multiple Sclerosis: on Diagnosis, Clinical Phenotypes, and Therapeutic Responses

Early-onset (pediatric and adolescent) multiple sclerosis (MS) is a well-established demyelinating disease that accounts for approximately 3-5% of all MS cases. Thus, identifying potential biomarkers that can reflect the pathogenic mechanisms, disease course and prognosis, and therapeutic response in such patients is of paramount importance. Myelin oligodendrocyte glycoprotein (MOG) has been regarded as a putative autoantigen and autoantibody target in patients with demyelinating diseases for almost three decades. However, recent studies have suggested that antibodies against MOG represent a distinct clinical entity of dominantly humoral profile, with a range of clinical phenotypes closely related to the age of onset, specific patterns of disease course, and responses to treatment. Furthermore, the major histocompatibility complex (MHC)—which has been regarded as the “gold standard” for attributing genetic burden in adult MS since the early 1970s—has also emerged as the primary genetic locus in early-onset MS, particularly with regard to the human leukocyte antigen (HLA) alleles DRB1⁎1501 and DRB1⁎0401. Recent studies have investigated the potential interactions among HLA, MOG, and environmental factors, demonstrating that early-onset MS is characterized by genetic, immunogenetic, immunological, and familial trait correlations. In this paper, we review recent evidence regarding HLA-genotyping and MOG antibodies—the two most important candidate biomarkers for early-onset MS—as well as their potential application in the diagnosis and treatment of MS.

[Familial multiple sclerosis in Tomsk region]

AIM

Multiple sclerosis (MS) has a multifactorial etiology. To explore a role of genetic factors in the pathogenesis of MS, the authors studied familial cases of MS.

MATERIAL AND METHODS

For an analysis of familial cases, a database of 320 MS patients registered in Tomsk region since 1980 till 2014 was used. The following items for each patient were recorded: disease onset, manifestation of disease, duration of first remission, rate of progression of disease.

RESULTS AND CONCLUSION

Nine families with several members with MS were identified. In 2014, the frequency of familial cases in the MS population of Tomsk region was 4.7%. The prevalence of familial MS was 1.4 cases per 100.000 of people. The younger age at disease onset and higher rate of disease progression measured with the EDSS in parent-child pairs were identified. The most families with several members with MS were characterized by clinical polymorphism of onset, duration and rate of disease progression.

SUMMIT (Serially Unified Multicenter Multiple Sclerosis Investigation): creating a repository of deeply phenotyped contemporary multiple sclerosis cohorts

BACKGROUND

There is a pressing need for robust longitudinal cohort studies in the modern treatment era of multiple sclerosis.

OBJECTIVE

Build a multiple sclerosis (MS) cohort repository to capture the variability of disability accumulation, as well as provide the depth of characterization (clinical, radiologic, genetic, biospecimens) required to adequately model and ultimately predict a patient's course.

METHODS

Serially Unified Multicenter Multiple Sclerosis Investigation (SUMMIT) is an international multi-center, prospectively enrolled cohort with over a decade of comprehensive follow-up on more than 1000 patients from two large North American academic MS Centers (Brigham and Women's Hospital (Comprehensive Longitudinal Investigation of Multiple Sclerosis at the Brigham and Women's Hospital (CLIMB; BWH)) and University of California, San Francisco (Expression/genomics, Proteomics, Imaging, and Clinical (EPIC))). It is bringing online more than 2500 patients from additional international MS Centers (Basel (Universitätsspital Basel (UHB)), VU University Medical Center MS Center Amsterdam (MSCA), Multiple Sclerosis Center of Catalonia-Vall d'Hebron Hospital (Barcelona clinically isolated syndrome (CIS) cohort), and American University of Beirut Medical Center (AUBMC-Multiple Sclerosis Interdisciplinary Research (AMIR)).

RESULTS AND CONCLUSION

We provide evidence for harmonization of two of the initial cohorts in terms of the characterization of demographics, disease, and treatment-related variables; demonstrate several proof-of-principle analyses examining genetic and radiologic predictors of disease progression; and discuss the steps involved in expanding SUMMIT into a repository accessible to the broader scientific community.

The immunogenetics of neurological disease

Genes encoding antigen-presenting molecules within the human major histocompatibility complex (MHC) account for the highest component of genetic risk for many neurological diseases, such as multiple sclerosis, neuromyelitis optica, Parkinson's disease, Alzheimer's disease, schizophrenia, myasthenia gravis and amyotrophic lateral sclerosis. Myriad genetic, immunological and environmental factors may contribute to an individual's susceptibility to neurological disease. Here, we review and discuss the decades long research on the influence of genetic variation at the MHC locus and the role of immunogenetic killer cell immunoglobulin-like receptor (KIR) loci in neurological diseases, including multiple sclerosis, neuromyelitis optica, Parkinson's disease, Alzheimer's disease, schizophrenia, myasthenia gravis and amyotrophic lateral sclerosis. The findings of immunogenetic association studies are consistent with a polygenic model of inheritance in the heterogeneous and multifactorial nature of complex traits in various neurological diseases. Future investigation is highly recommended to evaluate both coding and non-coding variation in immunogenetic loci using high-throughput high-resolution next-generation sequencing technologies in diverse ethnic groups to fully appreciate their role in neurological diseases.

HLA class II polymorphism in Saudi patients with multiple sclerosis

Several studies have investigated the association of different HLA antigens with multiple sclerosis (MS). However, only few studies have considered the association of high-resolution HLA type and MS with none yet from Saudi Arabia. The aim of this study was to investigate the association of HLA class II alleles with MS in the Saudi population. We used next-generation sequencing to investigate HLA association with MS. This study was conducted at King Abdulaziz Medical City in Riyadh, Saudi Arabia. We found that several HLA-DRB1 and DQB1 alleles were associated with MS. These alleles included HLA-DRB1*15:01 (odds ratio [OR]: 3.01; 95%, confidence interval [CI]: 1.68-5.54; P = .0001), HLA-DQB1*02:01 (OR: 1.76; 95% CI: 1.20-2.58; P = .0022), HLA-DQB1*06:02 (OR: 3.52; 95% CI: 1.87-6.86; P < .0001), and HLA-DQB1*06:03 (OR: 2.42; 95% CI: 1.16-5.25; P = 0.01). Interestingly, HLA-DRB1*15:01 was associated with increased risk of previous relapses. In addition, HLA-DRB1*15:01 and HLA-DQB1*06:02 were found to be associated with lower vitamin D levels. This study provides insights on the association of different HLA alleles with clinical characteristics and outcome of MS among Saudis. These insights can have future implications for the clinical management of MS based on the patient genetic profile.

Association of CYP2R1 rs10766197 with MS risk and disease progression

BACKGROUND

MS is a neurodegenerative autoimmune disease resulting from a complex interaction of genetic and environmental factors. Among these, vitamin D and genetic variants associated with vitamin D-metabolism gain great attention. The aim of our study was to assess five SNPs in NADSYN1 and CYP2R1 genes in relation to serum 25-OH-vitamin D3 levels in MS patients and controls.

METHODS

25-OH-vitamin D3 levels and genotyping of CYP2R1- and NADSYN1-SNPs were investigated both in MS patients and in healthy controls.

RESULTS

The analysis revealed lower 25-OH-vitamin D3 concentrations in MS patients than in controls and an association of rs10766197 CYP2R1 SNP with MS risk. After stratifying MS patients according to gender, we found that the minor allele A of rs10766197 had a higher frequency in men in comparison to women affected by MS. Additionally, the presence of allele A in men was associated with disease progression, assessed by EDSS and MSSS scores.

CONCLUSION

The findings of our study open new perspectives for a role of CYP2R1 in both risk and progression of MS, with sex-related differences.

Association of HLA Genetic Risk Burden With Disease Phenotypes in Multiple Sclerosis

IMPORTANCE

Although multiple HLA alleles associated with multiple sclerosis (MS) risk have been identified, genotype-phenotype studies in the HLA region remain scarce and inconclusive.

OBJECTIVES

To investigate whether MS risk-associated HLA alleles also affect disease phenotypes.

DESIGN, SETTING, AND PARTICIPANTS

A cross-sectional, case-control study comprising 652 patients with MS who had comprehensive phenotypic information and 455 individuals of European origin serving as controls was conducted at a single academic research site. Patients evaluated at the Multiple Sclerosis Center at University of California, San Francisco between July 2004 and September 2005 were invited to participate. Spinal cord imaging in the data set was acquired between July 2013 and March 2014; analysis was performed between December 2014 and December 2015.

MAIN OUTCOMES AND MEASURES

Cumulative HLA genetic burden (HLAGB) calculated using the most updated MS-associated HLA alleles vs clinical and magnetic resonance imaging outcomes, including age at onset, disease severity, conversion time from clinically isolated syndrome to clinically definite MS, fractions of cortical and subcortical gray matter and cerebral white matter, brain lesion volume, spinal cord gray and white matter areas, upper cervical cord area, and the ratio of gray matter to the upper cervical cord area. Multivariate modeling was applied separately for each sex data set.

RESULTS

Of the 652 patients with MS, 586 had no missing genetic data and were included in the HLAGB analysis. In these 586 patients (404 women [68.9%]; mean [SD] age at disease onset, 33.6 [9.4] years), HLAGB was higher than in controls (median [IQR], 0.7 [0-1.4] and 0 [-0.3 to 0.5], respectively; P = 1.8 × 10-27). A total of 619 (95.8%) had relapsing-onset MS and 27 (4.2%) had progressive-onset MS. No significant difference was observed between relapsing-onset MS and primary progressive MS. A higher HLAGB was associated with younger age at onset and the atrophy of subcortical gray matter fraction in women with relapsing-onset MS (standard β = -1.20 × 10-1; P = 1.7 × 10-2 and standard β = -1.67 × 10-1; P = 2.3 × 10-4, respectively), which were driven mainly by the HLA-DRB1*15:01 haplotype. In addition, we observed the distinct role of the HLA-A*24:02-B*07:02-DRB1*15:01 haplotype among the other common DRB1*15:01 haplotypes and a nominally protective effect of HLA-B*44:02 to the subcortical gray atrophy (standard β = -1.28 × 10-1; P = 5.1 × 10-3 and standard β = 9.52 × 10-2; P = 3.6 × 10-2, respectively).

CONCLUSIONS AND RELEVANCE

We confirm and extend previous observations linking HLA MS susceptibility alleles with disease progression and specific clinical and magnetic resonance imaging phenotypic traits.

Gene variants of adhesion molecules act as modifiers of disease severity in MS

Objective:

To assess the potential effect of variants in genes encoding molecules that are implicated in leukocyte trafficking into the CNS on the clinical phenotype of multiple sclerosis (MS).

Methods:

A total of 389 Greek MS cases and 336 controls were recruited in 3 MS centers from Cyprus and Greece. We genotyped 147 tagging single nucleotide polymorphisms (SNPs) in 9 genes encoding for P-selectin (SELP), integrins (ITGA4, ITGB1, and ITGB7), adhesion molecules (ICAM1, VCAM1, and MADCAM1), fibronectin 1 (FN1), and osteopontin (SPP1) involved in lymphocyte adhesion and trafficking into the CNS. Clinical end points of the study were age at MS onset and MS severity as measured by the Multiple Sclerosis Severity Score. Permutation testing was applied to all analyses.

Results:

SNPs rs6721763 of the ITGA4 and rs6532040 of the SPP1 were found to significantly influence disease severity (permutation p values: 3.00e-06 and 0.009884, respectively). SNP rs1250249 of the FN1 had a dose-dependent effect on age at disease onset (permutation p value: 0.0002).

Conclusions:

This study provides evidence implicating variants encoding adhesion molecules, responsible for lymphocyte adhesion and trafficking within the CNS, as modifiers of MS disease severity. These genetic biomarkers, which can be available at the time of diagnosis, may be used to assess the biological aggressiveness of the disease and thus guide decisions on treatment.

HLA genotype as a marker of multiple sclerosis prognosis: A pilot study

OBJECTIVE

The identification of a biomarker with prognostic value is an unmet need in multiple sclerosis (MS). The objective of this study was to investigate a possible association of HLA genotype with disease status and progression in MS, based on comprehensive and sensitive clinical and magnetic resonance imaging (MRI) parameters to measure disease effects.

METHOD

A total of 118 MS patients (79 females, 39 males) underwent HLA typing. Patient MS status was assessed at two time points in a 2-year interval, based on clinical scores (including EDSS, MSSS, T25FW, 9-HPT, SDMT, BVMT, CVLT-II) and MRI evaluations. Quantitative brain MRI values were obtained for whole brain atrophy, FLAIR lesion volume change and number of new lesions using MSmetrix. Predefined HLA patient groups were compared as of disease status and progression. Global assessment was achieved by an overall t-statistic and assessment per measurement by a Welch test and/or Mann Whitney U test. The effects of multiple covariates, including age, gender and disease duration as well as scan parameters, were also evaluated using a regression analysis.

RESULTS

The HLA-A*02 allele was associated with better outcomes in terms of MSSS, EDSS and new lesion count (Welch test p-value<0.05). The HLA-B*07 and HLA-B*44 alleles showed a global negative effect on disease status, although none of the measurements reached significance (p-value<0.05). Results for the HLA-DRB1*15, HLA-DQB1*06 and HLA-B*08 alleles were inconclusive. The influence of the confounding variables on the statistical analysis was limited.

A genetic basis for multiple sclerosis severity: Red herring or real?

Multiple Sclerosis (MS) is an autoimmune degenerative disease of the central nervous system, characterized by multifocal demyelination and neurodegeneration. The genetic architecture of MS is complex, where genetic risk has been attributed to over 100 polymorphic loci each with small odds ratios. MS is a highly heterogeneous disease with numerous clinical and paraclinical endophenotypes. To-date, no genetic variant has been associated with clinical outcome, however, evidence exists that MS outcomes, like risk, are to an extent also controlled by genetic variation. Here we summarise the current evidence for genetic determination of disease outcomes and make recommendations for future research directions.

Vitamin D receptor biochemical and genetic profiling and HLA-class II genotyping among Lebanese with multiple sclerosis - A pilot study

BACKGROUND

Multiple sclerosis (MS) is an autoimmune demyelinating disease affecting mostly young adult females with multifactorial etiology. Recent studies suggested that adequate vitamin D levels may lower the risk of developing MS.

OBJECTIVES

Our aim was to explore the relationship between vitamin D receptor (VDR) polymorphism, HLA-DR locus genotype, and serum vitamins D and A levels in the Lebanese population.

METHODS

Fifty MS patients were recruited for this study. The control group consisted of 48 healthy and 51 patients with other neurological disorders (non-MS). Biochemical analysis included serum 25 hydroxyvitamin D (25OHD) and vitamin A. Molecular analysis targeted VDR genotypes (ApaI, TaqI and BsmI) and low resolution HLA typing for DRB1 locus.

RESULTS

Healthy and non-MS groups had comparable parameters and were combined into one control group. No significant differences were found between MS and control groups for VDR genotypes. The frequency of HLA-DRB1*15 was significantly higher in MS patients (22%) compared to controls (8%) (p=0.018). Odds ratio for MS in the presence of DRB1*15 allele was 3.21 (p=0.018). Cosegregation with A (ApaI) and b (BsmI) alleles did not influence the risk for MS. 25OHD levels were significantly higher in MS patients compared to controls (p=0.002), due to more frequent oral supplementation (p=0.005). Vitamin A levels were comparable between the two groups. When all parameters were included in a logistic regression model adjusted for supplementation, only HLA-DRB1*15 (OR=3.42; p=0.027) contributed significantly to MS risk.

CONCLUSION

There was no association between serum vitamin D or A or VDR genotypes and MS. HLA-DRB1*15 was the major factor imposing more than 3 folds greater risk for developing MS among Lebanese.

Removing confounding factors via constraint-based clustering: An application to finding homogeneous groups of multiple sclerosis patients

OBJECTIVES

Confounding factors in unsupervised data can lead to undesirable clustering results. For example in medical datasets, age is often a confounding factor in tests designed to judge the severity of a patient's disease through measures of mobility, eyesight and hearing. In such cases, removing age from each instance will not remove its effect from the data as other features will be correlated with age. Motivated by the need to find homogeneous groups of multiple sclerosis (MS) patients, we apply our approach to remove physician subjectivity from patient data.

METHODS

We present a method based on constraint-based clustering to remove the impact of such confounding factors. Given knowledge about which feature (or set of features) is a confounding factor, call it F. Our method first partitions the data into b bins: if F is categorical, instances from the same category construct one bin; if F is numeric, then we split bins such that each bin contains instances of similar F value. Thus each instance is assigned to a single bin for factor F. We then remove feature F from each instance for the remaining steps. Next, we cluster the data separately in each bin. Using these clustering results, we generate pair-wise constraints and then run a constraint-based clustering algorithm to produce a final grouping.

RESULTS

In a series of experiments with synthetic datasets, we compare our proposed methods to detrending when one has numeric confounding factors. We apply our method to the Comprehensive Longitudinal Investigation of Multiple Sclerosis at Brigham and Womens Hospital dataset, and find a novel grouping of patients that can help uncover the factors that impact disease progression in MS.

CONCLUSIONS

Our method groups data removing the effect of confounding factors without making any assumptions about the form of the influence of these factors on the other features. We identified clusters of MS patients that have clinically recognizable differences. Because patients more likely to progress are found using this approach, our results have the potential to aid physicians in tailoring treatment decisions for MS patients.

The immunogenetics of multiple sclerosis: A comprehensive review

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system and common cause of non-traumatic neurological disability in young adults. The likelihood for an individual to develop MS is strongly influenced by her or his ethnic background and family history of disease, suggesting that genetic susceptibility is a key determinant of risk. Over 100 loci have been firmly associated with susceptibility, whereas the main signal genome-wide maps to the class II region of the human leukocyte antigen (HLA) gene cluster and explains up to 10.5% of the genetic variance underlying risk. HLA-DRB1*15:01 has the strongest effect with an average odds ratio of 3.08. However, complex allelic hierarchical lineages, cis/trans haplotypic effects, and independent protective signals in the class I region of the locus have been described as well. Despite the remarkable molecular dissection of the HLA region in MS, further studies are needed to generate unifying models to account for the role of the MHC in disease pathogenesis. Driven by the discovery of combinatorial associations of Killer-cell Immunoglobulin-like Receptor (KIR) and HLA alleles with infectious, autoimmune diseases, transplantation outcome and pregnancy, multi-locus immunogenomic research is now thriving. Central to immunity and critically important for human health, KIR molecules and their HLA ligands are encoded by complex genetic systems with extraordinarily high levels of sequence and structural variation and complex expression patterns. However, studies to-date of KIR in MS have been few and limited to very low resolution genotyping. Application of modern sequencing methodologies coupled with state of the art bioinformatics and analytical approaches will permit us to fully appreciate the impact of HLA and KIR variation in MS.

Antigen Presentation, Autoantigens, and Immune Regulation in Multiple Sclerosis and Other Autoimmune Diseases

Antigen presentation is in the center of the immune system, both in host defense against pathogens, but also when the system is unbalanced and autoimmune diseases like multiple sclerosis (MS) develop. It is not just by chance that a major histocompatibility complex gene is the major genetic susceptibility locus in MS; a feature that MS shares with other autoimmune diseases. The exact etiology of the disease, however, has not been fully understood yet. T cells are regarded as the major players in the disease, but most probably a complex interplay of altered central and peripheral tolerance mechanisms, T-cell and B-cell functions, characteristics of putative autoantigens, and a possible interference of environmental factors like microorganisms are at work. In this review, new data on all these different aspects of antigen presentation and their role in MS will be discussed, probable autoantigens will be summarized, and comparisons to other autoimmune diseases will be drawn.

The CIITA genetic polymorphism rs4774*C in combination with the HLA-DRB1*15:01 allele as a putative susceptibility factor to multiple sclerosis in Brazilian females

The objective of this study was to investigate the association between the HLA alleles at the DQA1, DQB1 and DRB1 loci, the CIITA genetic polymorphisms -168A/G and +1614G/C, and susceptibility to multiple sclerosis (MS) in a sample from Rio de Janeiro State, Brazil. Furthermore, we wished to determine whether any of these associations might be more significant in women compared with men. DNA samples from 52 relapsing-remitting MS (RRMS) patients and 126 healthy controls matched for sex and age were analyzed. We identified a significant HLA-DRB1*15:01-MS association that was female-specific (Odds Ratio (OR) = 4.78; p = 0.001). Furthermore, we observed that the +1614G/C mutation in combination with the HLA-DRB1*15:01 allele increased susceptibility to MS in females (OR = 4.55; p = 0.01). Together, these findings highlight the polygenic nature of MS.

Burden of risk variants correlates with phenotype of multiple sclerosis

BACKGROUND

More than 100 common variants underlying multiple sclerosis (MS) susceptibility have been identified, but their effect on disease phenotype is still largely unknown.

OBJECTIVE

The objective of this paper is to assess whether the cumulative genetic risk score of currently known susceptibility variants affects clinical presentation.

METHODS

A cumulative genetic risk score was based on four human leukocyte antigen (HLA) and 106 non-HLA risk loci genotyped or imputed in 842 Belgian MS patients and 321 controls. Non-parametric analyses were applied.

RESULTS

An increased genetic risk is observed for MS patients, including subsets such as oligoclonal band-negative and primary progressive MS patients, compared to controls. Within the patient group, a stronger association between HLA risk variants and the presence of oligoclonal bands, an increased immunoglobulin G (IgG) index and female gender was apparent. Results suggest an association between a higher accumulation of non-HLA risk variants and increased relapse rate as well as shorter relapse-free intervals after disease onset.

CONCLUSION

MS patients display a significantly increased genetic risk compared to controls, irrespective of disease course or presence of oligoclonal bands. Whereas the cumulative burden of non-HLA risk variants appears to be reflected in the relapses of MS patients, the HLA region influences intrathecal IgG levels.

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.

A single-nucleotide polymorphism in serine-threonine kinase 11, the gene encoding liver kinase B1, is a risk factor for multiple sclerosis

We identified a family in which five siblings were diagnosed with multiple sclerosis (MS) or clinically isolated syndrome. Several women in the maternal lineage have comorbidities typically associated with Peutz Jeghers Syndrome, a rare autosomal-dominant disease caused by mutations in the serine-threonine-kinase 11 (STK11) gene, which encodes liver kinase B1. Sequence analysis of DNA from one sibling identified a single-nucleotide polymorphism (SNP) within STK11 intron 5. This SNP (dbSNP ID: rs9282860) was identified by TaqMan polymerase chain reaction (PCR) assays in DNA samples available from two other siblings. Further screening was carried out in samples from 654 relapsing-remitting MS patients, 100 primary progressive MS patients, and 661 controls. The STK11-SNP has increased frequency in all female patients versus controls (odds ratio = 1.66, 95% CI = 1.05, 2.64, p = .032). The STK11-SNP was not associated with disease duration or onset; however, it was significantly associated with reduced severity (assessed by MS severity scores), with the lowest scores in patients who also harbored the HLA-DRB1*1501 allele. In vitro studies showed that peripheral blood mononuclear cells from members of the family were more sensitive to the mitochondrial inhibitor metformin than cells from MS patients with the major STK11 allele. The increased association of SNP rs9282860 in women with MS defines this variant as a genetic risk factor. The lower disease severity observed in the context of HLA-DRB1*1501 combined with limited in vitro studies raises the provocative possibility that cells harboring the STK11-SNP could be targeted by drugs which increase metabolic stress.

The intelligent use and clinical benefits of electronic medical records in multiple sclerosis

Electronic medical records (EMRs) are being quickly adopted in clinics around the world. This advancement can greatly enhance the clinical care of patients with multiple sclerosis (MS) by providing formats that allow easier review of medical documents and more structured avenues to store relevant information. MS clinicians should be involved with implementing and updating EMRs at their institutions to ensure EMR formats that benefit MS clinics. EMRs also provide opportunities for research studies of MS to access detailed, longitudinal data of MS disease course that would otherwise be difficult to collect.

Multiple sclerosis genetics

Familial aggregation and the studies of twins indicate that heredity contributes to multiple sclerosis (MS) risk. Immunologic studies of leukocyte antigens subsequently followed by gene-mapping techniques identified the primary MS susceptibility locus to be within the major histocompatibility complex (MHC). The primary risk allele is HLA-DRB1*15, although other alleles of this gene also influence MS susceptibility. Other genes within the MHC also contribute to MS susceptibility. Genome-wide association studies have identified over 50 additional common variants of genes across the genome. Estimates suggest that there may be as many as 200 genes involved in MS susceptibility. In addition to these common polymorphisms, studies have identified several rare risk alleles in some families. Interestingly, the majority of the genes identified have known immunologic functions and many contribute to the risk of inheriting other autoimmune diseases. Genetic variants in the vitamin D metabolic pathway have also been identified. That vitamin D contributes to MS susceptibility as both an environmental as well as genetic risk factor underscores the importance of this metabolic pathway in disease pathogenesis. Current efforts are focused on understanding how the myriad of genetic risk alleles interact within networks to influence MS risk at family level as well as within populations.

Genetic variation in the extended major histocompatibility complex and susceptibility to childhood acute lymphoblastic leukemia: a review of the evidence

The enduring suspicion that infections and immunologic response may play a role in the etiology of childhood leukemia, particularly acute lymphoblastic leukemia (ALL), is now supported, albeit still indirectly, by numerous epidemiological studies. The cumulative evidence includes, for example, descriptive observations of a peculiar peak incidence at age 2–5 years for ALL in economically developed countries, clustering of cases in situations of population mixing associated with unusual patterns of personal contacts, associations with various proxy measures for immune modulatory exposures early in life, and genetic susceptibility conferred by variation in genes involved in the immune system. In this review, our focus is the extended major histocompatibility complex (MHC), an approximately 7.6 Mb region that is well-known for its high-density of expressed genes, extensive polymorphisms exhibiting complex linkage disequilibrium patterns, and its disproportionately large number of immune-related genes, including human leukocyte antigen (HLA). First discovered through the role they play in transplant rejection, the classical HLA class I (HLA-A, -B, and -C) and class II (HLA-DR, HLA-DQ, and HLA-DP) molecules reside at the epicenter of the immune response pathways and are now the targets of many disease susceptibility studies, including those for childhood leukemia. The genes encoding the HLA molecules are only a minority of the over 250 expressed genes in the xMHC, and a growing number of studies are beginning to evaluate other loci through targeted investigations or utilizing a mapping approach with a comprehensive screen of the entire region. Here, we review the current epidemiologic evidence available to date regarding genetic variation contained within this highly unique region of the genome and its relationship with childhood ALL risk.

Subcutaneous interferon β-1a may protect against cognitive impairment in patients with relapsing-remitting multiple sclerosis: 5-year follow-up of the COGIMUS study

OBJECTIVE

To assess the effects of subcutaneous (sc) interferon (IFN) -1a on cognition over 5 years in mildly disabled patients with relapsing-remitting multiple sclerosis (RRMS).

METHODS

Patients aged 18-50 years with RRMS (Expanded Disability Status Scale score ≤4.0) who had completed the 3-year COGIMUS study underwent standardized magnetic resonance imaging, neurological examination, and neuropsychological testing at years 4 and 5. Predictors of cognitive impairment at year 5 were identified using multivariate analysis.

RESULTS

Of 331 patients who completed the 3-year COGIMUS study, 265 participated in the 2-year extension study, 201 of whom (75.8%; sc IFN β-1a three times weekly: 44 µg, n = 108; 22 µg, n = 93) completed 5 years' follow-up. The proportion of patients with cognitive impairment in the study population overall remained stable between baseline (18.0%) and year 5 (22.6%). The proportion of patients with cognitive impairment also remained stable in both treatment groups between baseline and year 5, and between year 3 and year 5. However, a significantly higher proportion of men than women had cognitive impairment at year 5 (26.5% vs 14.4%, p = 0.046). Treatment with the 22 versus 44 µg dose was predictive of cognitive impairment at year 5 (hazard ratio 0.68; 95% confidence interval 0.48-0.97).

CONCLUSIONS

This study suggests that sc IFN β-1a dose-dependently stabilizes or delays cognitive impairment over a 5-year period in most patients with mild RRMS. Women seem to be more protected against developing cognitive impairment, which may indicate greater response to therapy or the inherently better prognosis associated with female sex in MS.

HLA-DR15-derived self-peptides are involved in increased autologous T cell proliferation in multiple sclerosis

The HLA-DR15 haplotype confers the largest part of the genetic risk to develop multiple sclerosis, a prototypic CD4+ T cell-mediated autoimmune disease. The mechanisms how certain HLA-class II molecules functionally contribute to autoimmune diseases are still poorly understood, but probably involve shaping an autoimmune-prone T cell repertoire during central tolerance in the thymus and subsequently maintaining or even expanding it in the peripheral immune system. Self-peptides that are presented by disease-associated HLA-class II molecules most likely play important roles during both processes. Here, we examined the functional involvement of the HLA-DR15 haplotype in autologous proliferation in multiple sclerosis and the contribution of HLA-DR15 haplotype-derived self-peptides in an in vitro system. We observe increased autologous T cell proliferation in patients with multiple sclerosis in relation to the multiple sclerosis risk-associated HLA-DR15 haplotype. Assuming that the spectrum of self-peptides that is presented by the two HLA-DR15 allelic products is important for sustaining autologous proliferation we performed peptide elution and identification experiments from the multiple sclerosis-associated DR15 molecules and a systematic analysis of a DR15 haplotype-derived self-peptide library. We identify HLA-derived self-peptides as potential mediators of altered autologous proliferation. Our data provide novel insights about perturbed T cell repertoire dynamics and the functional involvement of the major genetic risk factor, the HLA-DR15 haplotype, in multiple sclerosis.

The importance of HLA DRB1 gene allele to clinical features and disability in patients with multiple sclerosis in Lithuania

BACKGROUND

The association of HLA DRB1 alleles with susceptibility to multiple sclerosis (MS) has been consistently reported although its effect on the clinical features and disability is still unclear probably due to diversity in ethnicity and geographic location of the studied populations. The aim of the present study was to investigate the influence of HLA DRB1 alleles on the clinical features and disability of the patients with MS in Lithuania.

METHODS

This was a prospective study of 120 patients with MS. HLA DRB1 alleles were genotyped using the polymerase chain reaction.

RESULTS

The first symptoms of MS in patients with HLA DRB1*15 allele manifested at younger age than in those without this allele (28.32 +/- 5.49 yrs vs. 30.94 +/- 8.43 yrs, respectively, p = 0.043). HLA DRB1*08 allele was more prevalent among relapsing-remitting (RR) MS patients than among patients with progressive course of MS (25.0% vs. 8.3%, respectively, chi^2 = 6.000, p = 0.05). MS patients with this allele had lower relapse rate than those without this allele (1.00 +/- 0.97 and 1.44 +/- 0.85, respectively, p = 0.043). Degree of disability during the last visit was lower among the patients with HLA DRB1*08 allele (EDSS score 3.15 +/- 1.95 vs. 4.49 +/- 1.96, p = 0.006), and higher among those with HLA DRB1*15 allele (EDSS score 4.60 +/- 2.10 vs.4.05 +/- 1.94, p = 0.047) compared to patients without these alleles but there were no significant associations between these alleles and the duration of the disease to disability. HLA DRB1*08 allele (OR = 0.18, 95% CI 0,039-0,8, p = 0.029) was demonstradet to be independent factor to take a longer time to reach an EDSS of 6, while HLA DRB1*01 allele (OR = 5.92, 95% CI 1,30-26,8, p = 0.021) was related in a shorter time to reach and EDSS of 6. Patients with HLA DRB1*08 allele had lower IgG index compared to patients without this allele (0.58 +/- 0.17 and 0.73 +/- 0.31, respectively, p = 0.04), and HLA DRB1*15 allele was more often found among MS patients with oligoclonal bands (OCBs) in cerebrospinal fluid than among those without OCBs (OR 2.3, CI 95% 1.017-5.301; p = 0.043).

CONCLUSIONS

HLA DRB1*15 allele was related with an earlier manifestation of the first MS symptoms, progressive course of the disease and higher degree of disability. HLA DRB1*08 allele was more prevalent among the RR MS patients and was associated with the lower rate of relapse, degree of disability and IgG index.

Progress in multiple sclerosis genetics

A genetic component in the susceptibility to multiple sclerosis (MS) has long been known, and the first and major genetic risk factor, the HLA region, was identified in the 1970’s. However, only with the advent of genome-wide association studies in the past five years did the list of risk factors for MS grow from 1 to over 50. In this review, we summarize the search for MS risk genes and the latest results. Comparison with data from other autoimmune and neurological diseases and from animal models indicates parallels and differences between diseases. We discuss how these translate into an improved understanding of disease mechanisms, and address current challenges such as genotype-phenotype correlations, functional mechanisms of risk variants and the missing heritability.

Multiple sclerosis susceptibility loci do not alter clinical and MRI outcomes in clinically isolated syndrome

It has not yet been established whether genetic predictors of multiple sclerosis (MS) susceptibility also influence disease severity and accumulation of disability. Our aim was to evaluate associations between 16 previously validated genetic susceptibility markers and MS phenotype. Patients with clinically isolated syndrome verified by positive magnetic resonance imaging (MRI) and cerebrospinal fluid findings (n=179) were treated with interferon-β. Disability and volumetric MRI parameters were evaluated regularly for 2 years. Sixteen single-nucleotide polymorphisms (SNPs) previously validated as predictors of MS susceptibility in our cohort and their combined weighted genetic risk score (wGRS) were tested for associations with clinical (conversion to MS, relapses and disability) and MRI disease outcomes (whole brain, grey matter and white matter volumes, corpus callosum cross-sectional area, brain parenchymal fraction, T2 and T1 lesion volumes) 2 years from disease onset using mixed-effect models. We have found no associations between the tested SNPs and the clinical or MRI outcomes. Neither the combined wGRS predicted MS activity and progression over 2-year follow-up period. Power analyses confirmed 90% power to identify clinically relevant changes in all outcome variables. We conclude that the most important MS susceptibility loci do not determine MS phenotype and disease outcomes.

Sexual disparities in the incidence and course of MS

Multiple sclerosis (MS) affects three times more women than men and this ratio appears to be increasing. However male patients experience increased disease progression, brain atrophy, and cognitive impairment. Gonadal hormones may modulate these sex differences. For example, female puberty heralds an increased risk of MS, and during pregnancy disease activity is milder, with an increased risk of postpartum relapses. Gonadal hormones likely have complex and inflammatory and neuroprotective effects, and may interact with other disease modulators, such as vitamin D. Sex differences in the heritability of disease susceptibility genes implicate a role for epigenetic modification. Many questions remain, including the impact of sex on treatment response and epigenetic changes, and the modulatory potential of hormonal treatments. This article summarizes what is known about sexual dimorphism in MS onset and course, as well as potential interactions between sex and other factors influencing MS pathogenesis, incidence and severity.