Opposing effects of the HLA-DRB1*0301-DQB1*0201 haplotype on the risk for multiple sclerosis in diverse Arab populations in Israel

Familial vs sporadic multiple sclerosis in the Israeli population: Differences in ethnicity distribution and disease progression, with anticipation in successive generations

BACKGROUND

Multiple Sclerosis (MS) may cluster in families, an entity known as familial MS (FMS), possibly due to aggregation of genetic and environmental factors. Though previous studies have characterized FMS in different populations, no study to the best of our knowledge has yet characterized FMS in the unique Israeli population, which is comprised of relatively endogamous ethnicities. Our goal in this study was to compare demographic and clinical characteristics between FMS and sporadic MS (SMS), and to search for intra-familial patterns.

METHODS

In a retrospective study of 101 FMS patients and 508 SMS patients, ethnicity and sex distribution was assessed. Clinical aspects were compared between 172 paired FMS and SMS patients, matched for sex, age and ethnicity, and between generations of the FMS cohort.

RESULTS

Females comprised 75.3 % of FMS and 67.5 % of SMS patients (p = 0.1). Ethnic distribution was significantly different between FMS and SMS (p = 0.014), with the former comprising a higher proportion of Christian-Arabs (15.4% vs. 5.1 %, p = 0.004) and lower proportion of Jews (60% vs. 74.2 %, p = 0.016). Age at disease onset or diagnosis, frequency of positive Oligoclonal bands and comorbidity of other autoimmune/inflammatory disease or chronic diseases was comparable between FMS and SMS, yet motor symptoms at onset were more prevalent in FMS (34% vs. 20 %, p = 0.02). Annualized relapse rates throughout 10 years from onset were comparable. Among FMS, mean Expanded-Disability-Status-Scale (EDSS) and slope of deterioration in EDSS over 20 years from diagnosis were higher (p = 0.0004 and p = 0.023, respectively), time to EDSS ≥ 3 was shorter (7.1 vs. 12.1 years, HR 1.6, p = 0.036) and MS-Severity-Score (MSSS) was higher (3.84 vs. 2.95, p = 0.04), compared to SMS. Following adjustment for smoking, which tended to be higher among FMS patients (P = 0.06), mean EDSS and slope of deterioration in EDSS over 20 years remained significantly higher (p = 0.0006 and p = 0.025, respectively) in FMS, time to EDSS ≥ 3 tended to be higher (HR 1.5, p = 0.06), while MSSS was comparable. An inter-generational analysis of the total FMS cohort, as well as an intra-familial analysis, both adjusted for year of diagnosis, revealed significantly earlier age of onset (p < 0.0001 and p < 0.0001) and diagnosis (p = 0.001 and p < 0.0001) in the younger compared to the older generations, respectively.

CONCLUSION

In this Israeli cohort, the proportions of specific ethnicities differ between FMS and SMS, indicating that FMS has a population-specific prevalence pattern, and that further investigation for susceptibility genes is warranted. Disease progression is faster in FMS patients and anticipation is observed in families with multiple cases of MS. Closer surveillance and application of a pro-active induction or early highly-effective therapeutic strategy for FMS patients should be considered, to reduce high disease activity and fast disability progression.

High-resolution DNA methylation screening of the major histocompatibility complex in multiple sclerosis

Background

The HLA-DRB1 gene in the major histocompatibility complex (MHC) region in chromosome 6p21 is the strongest genetic factor identified as influencing multiple sclerosis (MS) susceptibility. DNA methylation changes associated with MS have been consistently detected at the MHC region. However, understanding the full scope of epigenetic regulations of the MHC remains incomplete, due in part to the limited coverage of this region by standard whole genome bisulfite sequencing or array-based methods.

Methods

We developed and validated an MHC capture protocol coupled with bisulfite sequencing and conducted a comprehensive analysis of the MHC methylation landscape in blood samples from 147 treatment naïve MS study participants and 129 healthy controls.

Results

We identified 132 differentially methylated region (DMRs) within MHC region associated with disease status. The DMRs overlapped with established MS risk loci. Integration of the MHC methylome with human leukocyte antigen (HLA) genetic data indicate that the methylation changes are significantly associated with HLA genotypes. Using DNA methylation quantitative trait loci (mQTL) mapping and the causal inference test (CIT), we identified 643 cis-mQTL-DMRs paired associations, including 71 DMRs possibly mediating causal relationships between 55 single nucleotide polymorphisms (SNPs) and MS risk.

Results

The results describe MS-associated methylation changes in MHC region and highlight the association between HLA genotypes and methylation changes. Results from the mQTL and CIT analyses provide evidence linking MHC region variations, methylation changes, and disease risk for MS.

Multiple Sclerosis-Associated Gut Microbiome in the Israeli Diverse Populations: Associations with Ethnicity, Gender, Disability Status, Vitamin D Levels, and Mediterranean Diet

Microbiome dysbiosis is increasingly being recognized as implicated in immune-mediated disorders including multiple sclerosis (MS). The microbiome is modulated by genetic and environmental factors including lifestyle, diet, and drug intake. This study aimed to characterize the MS-associated gut microbiome in the Israeli populations and to identify associations with demographic, dietary, and clinical features. The microbiota from 57 treatment-naive patients with MS (PwMS) and 43 age- and gender-matched healthy controls (HCs) was sequenced and abundance compared. Associations between differential microbes with demographic or clinical characteristics, as well as diet and nutrient intake, were assessed. While there was no difference in α- or β-diversity of the microbiome, we identified 40 microbes from different taxonomic levels that differ in abundance between PwMS and HCs, including Barnesiella, Collinsella, Egerthella, Mitsuokella, Olsenella Romboutsia, and Succinivibrio, all enhanced in PwMS, while several members of Lacnospira were reduced. Additional MS-differential microbes specific to ethnicity were identified. Several MS-specific microbial patterns were associated with gender, vitamin D level, Mediterranean diet, nutrient intake, or disability status. Thus, PwMS have altered microbiota composition, with distinctive patterns related to geographic locations and population. Microbiome dysbiosis seem to be implicated in disease progression, gender-related differences, and vitamin D-mediated immunological effects recognized in MS. Dietary interventions may be beneficial in restoring a "healthy microbiota" as part of applying comprehensive personalized therapeutic strategies for PwMS.

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.

Clinical and MRI characteristics of multiple sclerosis in patients of Middle Eastern and North African ancestry residing in Ontario, Canada

BACKGROUND

Multiple sclerosis (MS) incidence is rising in traditionally low-burden regions, including the Middle East and North Africa (MENA).

OBJECTIVES

Our objective was to evaluate disease characteristics in MS patients of MENA descent (MENA-MS).

METHODS

MENA-MS patients and age- and sex-matched MS patients of European descent (EUR-MS) were identified through the MS Clinic Registry of St. Michael's Hospital in Toronto, Canada. Disease activity and severity were evaluated by the annualized relapse rate (ARR), magnetic resonance imaging (MRI) activity, change in the Expanded Disability Status Scale (EDSS), progression index (PI), and MS Severity Score (MSSS).

RESULTS

All MS patients within the registry identified to be of MENA origin (n = 192), and age- and sex-matched EUR-MS patients were included. Mean age was 42.9 years, 67% female. A total of 25% and 24% of EUR-MS and MENA-MS had progressive disease, with similar mean disease durations (11.5 and 11.4 years, respectively). Clinical and radiological disease activity (ARR, proportion with new/enlarging MRI lesions) was similar. MENA-MS showed greater disability progression over time (EDSS change = 0.24 vs. 0.06, p = 0.01), a higher MSSS (3.12 vs. 2.67, p = 0.04), and higher PI (0.34 vs. 0.27, p = 0.07).

CONCLUSION

MENA-MS patients demonstrate higher disease severity compared to EUR-MS patients, despite having similar inflammatory measures of disease activity, with disability progression in the absence of relapses. These observations illustrate the importance of the intersections of environmental, socioeconomic, and genetic determinants in optimizing individualized MS care.

Novel findings of HLA association with anti-LGI1 encephalitis: HLA-DRB1*03:01 and HLA-DQB1*02:01

This study was to investigate whether autoimmune encephalitis is associated with the human leukocyte antigen (HLA) genotypes in Chinese Han population. We compared and analyzed the HLA genotypes of 101 patients with autoimmune encephalitis (77 anti-NMDAR, 11 anti-LGI1 and 13 anti-GABA_BR antibody, respectively) to the 200 healthy control groups. Our results showed that the DRB1*03:01 or DQB1*02:01 allele and the extended DRB1*03:01 ~ DQB1*02:01 haplotype represented the strong susceptibility locus for anti-LGI1 encephalitis (OR = 18.84, 95% CI = 5.01-70.89, Pc = 0.004; OR = 18.84, 95% CI = 5.01-70.89, Pc = 0.004; OR = 18.84, 95% CI = 5.01-70.89, Pc = 0.001). Additionally, the DRB1*08:03 ~ DQB1*06:01 or B*08:01 ~ C*07:02 haplotype was likely to be associated with anti-LGI1 encephalitis (OR = 10.23, 95% CI = 2.87-36.42, Pc = 0.039; OR = 74.62, 95% CI = 6.97-799.06, Pc = 0.043). No statistically significant differences were found for HLA association between patients with anti-NMDAR or anti-GABA_BR encephalitis and healthy controls. These results indicated that HLA subtypes were only associated with anti-LGI1 encephalitis.

Multiple sclerosis and human leukocyte antigen genotypes: Focus on the Middle East and North Africa region

Recent reports have demonstrated that the prevalence of multiple sclerosis (MS) is increasing in the Middle East and North Africa region. There is also emerging evidence regarding the genetic components of MS risk. This review provides an overview of the role of genetic factors in MS susceptibility by examining human leukocyte antigen loci in patients within the Middle East and North Africa region. Most of the genetic studies conducted in the Middle East and North Africa region have been based on case–control designs, which cannot confirm direct causality of genetic variants on MS susceptibility. Moreover, there are very limited and inconsistent studies on human leukocyte antigen class I and II (DQA and DQB) in MS patients of the Middle East and North Africa region. To identify common risk haplotypes in the Middle East and North Africa region or its sub-populations, further longitudinal studies will be required.

Shifting paradigms in multiple sclerosis: from disease-specific, through population-specific toward patient-specific

PURPOSE OF REVIEW

In recent years we notice paradigm shifts in the understanding of multiple sclerosis (MS), leading to important transition in the patients' management. This review discusses some of the recent findings and developments underlying the conceptual changes being translated from 'treating the disease' to 'treating the patient' with MS (PwMS).

RECENT FINDINGS

Applying advanced technologies combined with cross-disciplinary efforts in the fields of neuropathology, neuroimmunology, neurobiology, and neuroimaging, together with clinical neurology provided support for the notion that MS is not a single disease but rather a spectrum. Predictive markers of disease subtypes, disease activity and response to therapy are being developed; some already applied to practice, allowing informed management. In parallel, population-specific issues, some genetic-driven, others caused by environmental (sun-exposure, life-style, etc.), gender-related (hormones) and epigenetic factors, are being elucidated. Additionally, patient empowerment-based approaches, including integration of patient-reported outcome measures (PRO) as well as tools to enhance patients' adherence to medications, are being developed, some already provided as part of emerging mobile-health technologies.

SUMMARY

Developments in the MS field, elucidating disease subtypes and interpopulation diversities, together with integration of patient-centered approaches, allow transition toward precision medicine in MS clinical trials and patient care.

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.

The Role of HLA in MS Susceptibility and Phenotype

One of the most consistent findings in multiple sclerosis (MS) is that development of MS is linked with carriage of the class II human leucocyte antigen (HLA) molecule HLA-DRB1*15:01; around 60 % of Caucasian MS patients carry this allele compared to 25-30 % of ethnically matched healthy individuals. However, other HLA molecules have also been linked to the development of MS. In this chapter, the association between different HLA types and susceptibility to MS will be reviewed, and other linkages between the carriage of specific HLA molecules and clinical and experimental findings in MS will be considered.

C-reactive protein and complement components in patients with pathological myopia

PURPOSE

To investigate the association between pathological myopia (PM) and immunological/inflammatory markers and to identify the possible risk factors for the formation of myopic choroidal neovascularization (mCNV).

METHODS

One hundred fourteen unrelated subjects were recruited: 63 PM patients (PM group) with spherical equivalent of at least -8.00 diopters (range, -8.00 to -25.00) and axial length exceeding 26.5 mm, accompanied by characteristic pathologic changes, and 51 emmetropic age- and sex-matched individuals (control group) with spherical equivalent within ±1.0 diopter in both eyes. In the PM group, patients were assigned to two subgroups, mCNV group and no CNV group, according to the results of fluorescein angiography. Serum high-sensitivity C-reactive protein (hs-CRP) and complement profile (C3, C4, and CH50) were assayed. Statistical analysis was performed between the two groups. Binary logistic regression analysis was used to analyze the relative risk factors that were associated with the development of mCNV in the PM group patients.

RESULTS

The range of axial length was 26.50 to 37.08 mm in the PM group and 22.32 to 24.56 mm in the control group. There were 24 patients in the mCNV group and 39 patients in the no CNV group. The PM group patients had significantly higher serum hs-CRP (p = 0.033), C3 (p = 0.004), and CH50 (p < 0.001) compared with the control group patients. There were no significant differences between the two groups for C4 level (p = 0.071). Binary logistic regression analysis, which included hs-CRP, C3, C4, CH50, age, and sex as covariates, showed that C3 (p = 0.03) and age (p = 0.01) were risk factors for mCNV, whereas serum hs-CRP, C4, CH50, and sex were not statistically significant predictors of mCNV in the PM group patients (p > 0.05).

CONCLUSIONS

Our data support the hypothesis that immunological/inflammatory markers, namely hs-CRP, C3, and CH50 may play an important role in the development of PM, and that C3 level may be a predictive risk factor for mCNV formation.

Multiple sclerosis in diverse populations: characteristics in distinct Arab ethnicities in Israel

Background:

Multiple sclerosis (MS) prevalence and genetic susceptibility varies among the different ethnic groups of Jews and Arabs in Israel.

Objective:

Characterization of MS disease course in Christian, Muslim and Druze Arabs in Israel.

Methods:

Historical cohort and three-year follow-up cohort analyses based on interviews and clinical charts of 149 Arab MS patients (78 Muslims, 49 Christians and 22 Druze) from three MS centers in Israel. Significant findings were adjusted for use of disease modifying therapy.

Results:

Age of onset (means between 30 and 31 years) and incomplete recovery rates after the first relapse (~50%) were similar for Christian, Muslim and Druze patients. Low rates of primary progressive MS (≤1%) were observed. Differences between the ethnicities in the time from onset to the second neurological episode were observed among females, but not males. Druze and Muslim women were more likely to have a second event within two years from the first event compared with Christians (odds ratios =8.8, p= 0.02; odds ratio=6.6, p=0.007 respectively). Trends for higher annual relapse rates, annual disability progression rates and MS Severity Scores were observed among the Druze.

Conclusions:

Among the Israeli Arab female MS patients, Druze and Muslims exhibit a more rapid disease course in comparison with Christians. Further elucidation of population-specific MS phenotypes may contribute to improved disease management.

DRB1*03:01 haplotypes: differential contribution to multiple sclerosis risk and specific association with the presence of intrathecal IgM bands

Background

Multiple sclerosis (MS) is a multifactorial disease with a genetic basis. The strongest associations with the disease lie in the Human Leukocyte Antigen (HLA) region. However, except for the DRB1*15:01 allele, the main risk factor associated to MS so far, no consistent effect has been described for any other variant. One example is HLA-DRB1*03:01, with a heterogeneous effect across populations and studies. We postulate that those discrepancies could be due to differences in the diverse haplotypes bearing that allele. Thus, we aimed at studying the association of DRB1*03:01 with MS susceptibility considering this allele globally and stratified by haplotypes. We also evaluated the association with the presence of oligoclonal IgM bands against myelin lipids (OCMB) in cerebrospinal fluid.

Methods

Genotyping of HLA-B, -DRB1 and -DQA1 was performed in 1068 MS patients and 624 ethnically matched healthy controls. One hundred and thirty-nine MS patients were classified according to the presence (M+, 58 patients)/absence (M−, 81 patients) of OCMB. Comparisons between groups (MS patients vs. controls and M+ vs. M−) were performed with the chi-square test or the Fisher exact test.

Results

Association of DRB1*03:01 with MS susceptibility was observed but with different haplotypic contribution, being the ancestral haplotype (AH) 18.2 the one causing the highest risk. Comparisons between M+, M− and controls showed that the AH 18.2 was affecting only M+ individuals, conferring a risk similar to that caused by DRB1*15:01.

Conclusions

The diverse DRB1*03:01-containing haplotypes contribute with different risk to MS susceptibility. The AH 18.2 causes the highest risk and affects only to individuals showing OCMB.

Genotype and ancestry modulate brain's DAT availability in healthy humans

The dopamine transporter (DAT) is a principal regulator of dopaminergic neurotransmission and its gene (the SLC6A3) is a strong biological candidate gene for various behavioral- and neurological disorders. Intense investigation of the link between the SLC6A3 polymorphisms and behavioral phenotypes yielded inconsistent and even contradictory results. Reliance on objective brain phenotype measures, for example, those afforded by brain imaging, might critically improve detection of DAT genotype-phenotype association. Here, we tested the relationship between the DAT brain availability and the SLC6A3 genotypes using an aggregate sample of 95 healthy participants of several imaging studies. These studies employed positron emission tomography (PET) with [¹¹C]cocaine wherein the DAT availability was estimated as Bmax/Kd; while the genotype values were obtained on two repeat polymorphisms--3-UTR- and intron 8--VNTRs. The main findings are the following: 1) both polymorphisms analyzed as single genetic markers and in combination (haplotype) modulate DAT density in midbrain; 2) ethnic background and age influence the strength of these associations; and 3) age-related changes in DAT availability differ in the 3-UTR and intron 8--genotype groups.

Multiple sclerosis pharmacogenetics: personalized approach towards tailored therapeutics

Multiple sclerosis (MS) is a chronic autoimmune disease, where T-cells attack the myelin sheath in the central nervous system (CNS), characterized by relapsing-remitting episodes, or gradually increasing severity of symptoms and disability that accumulate over time. While current MS therapies have been proven in clinical trials to provide significant benefits, they cater only to subsets of patients. Moreover, there is an acute need to identify the most effective and safe treatment appropriate for each patient prospectively, since early intervention has been proven to prevent accumulation of irreversible dysfunction. In this review we discuss the current state-of-the-art in pharmacogenetic research as applied to the common marketed and in-development MS treatments, with respect to both efficacy and safety aspects. We conclude by discussing the relevance of pharmacogenetics and other biomarkers to the prediction, prevention and personalization of MS medications in the horizon.