Mimics of Pediatric Small Vessel Primary Angiitis of the Central Nervous System.

OBJECTIVE: Small vessel primary angiitis of the central nervous system is a rare and often severe disease characterized by central nervous system-restricted inflammatory vasculitis on histopathology. Diagnosis requires brain biopsy for confirmation and is suggested prior to starting immunotherapy when feasible. However, emerging evidence suggests that other neuroinflammatory conditions may have a clinical and radiographic phenotype that mimics small vessel primary angiitis, at times with overlapping pathologic features as well. Such diagnoses, including myelin oligodendrocyte glycoprotein antibody-associated disease and central nervous system-restricted hemophagocytic lymphohistiocytosis, can be non-invasively diagnosed with serum antibody or genetic testing that would prompt different monitoring and treatment paradigms. To determine the ultimate diagnosis of patients who were suspected prior to biopsy to have small vessel primary angiitis, we reviewed the clinical, radiographic, and pathological features of a cohort of patients at a single center undergoing brain biopsy for non-oncologic indications. METHODS: Clinical data were retrospectively extracted from the medical record. Pathology and neuroimaging review was conducted. RESULTS: We identified 21 patients over a 19-year time-period, of whom 14 (66.7%) were ultimately diagnosed with entities other than small vessel primary angiitis that would have obviated the need for brain biopsy. Diagnoses included anti-myelin oligodendrocyte glycoprotein antibody associated disease (n = 9), central nervous system-restricted hemophagocytic lymphohistiocytosis (n = 3), anti-GABAA receptor encephalitis (n = 1), and Aicardi-Goutières syndrome (n = 1). INTERPRETATION: This study highlights the importance of pursuing now readily available non-invasive testing for mimicking diagnoses before performing a brain biopsy for suspected small vessel primary angiitis of the central nervous system. ANN NEUROL 2023;93:109-119.

MOG and AQP4 Antibodies among Children with Multiple Sclerosis and Controls.

OBJECTIVE: The purpose of this study was to determine the frequency of myelin oligodendrocyte glycoprotein (MOG)-IgG and aquaporin-4 (AQP4)-IgG among patients with pediatric-onset multiple sclerosis (POMS) and healthy controls, to determine whether seropositive cases fulfilled their respective diagnostic criteria, to compare characteristics and outcomes in children with POMS versus MOG-IgG-associated disease (MOGAD), and identify clinical features associated with final diagnosis. METHODS: Patients with POMS and healthy controls were enrolled at 14 US sites through a prospective case-control study on POMS risk factors. Serum AQP4-IgG and MOG-IgG were assessed using live cell-based assays. RESULTS: AQP4-IgG was negative among all 1,196 participants, 493 with POMS and 703 healthy controls. MOG-IgG was positive in 30 of 493 cases (6%) and zero controls. Twenty-five of 30 patients positive with MOG-IgG (83%) had MOGAD, whereas 5 of 30 (17%) maintained a diagnosis of multiple sclerosis (MS) on re-review of records. MOGAD cases were more commonly in female patients (21/25 [84%] vs 301/468 [64%]; p = 0.044), younger age (mean = 8.2 ± 4.2 vs 14.7 ± 2.6 years; p < 0.001), more commonly had initial optic nerve symptoms (16/25 [64%] vs 129/391 [33%]; p = 0.002), or acute disseminated encephalomyelitis (ADEM; 8/25 [32%] vs 9/468 [2%]; p < 0.001), and less commonly had initial spinal cord symptoms (3/20 [15%] vs 194/381 [51%]; p = 0.002), serum Epstein-Barr virus (EBV) positivity (11/25 [44%] vs 445/468 [95%]; p < 0.001), or cerebrospinal fluid oligoclonal bands (5/25 [20%] vs 243/352 [69%]; p < 0.001). INTERPRETATION: MOG-IgG and AQP4-IgG were not identified among healthy controls confirming their high specificity for pediatric central nervous system (CNS) demyelinating disease. Five percent of those with prior POMS diagnoses ultimately had MOGAD; and none had AQP4-IgG positivity. Clinical features associated with a final diagnosis of MOGAD in those with suspected MS included initial ADEM phenotype, younger age at disease onset, and lack of EBV exposure. ANN NEUROL 2023;93:271-284.

Predictors of a relapsing course in myelin oligodendrocyte glycoprotein antibody-associated disease.

BACKGROUND: Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a recently described demyelinating disorder, and children represent about 50% of all cases. Almost half of the patients experience relapses, but very few studies have evaluated predictors of relapse risk, challenging clinical management. The study aimed to identify predictors at MOGAD onset that are associated with a relapsing course. METHODS: Prospectively collected data from paediatric patients with MOGAD seen by the US Network of Paediatric MS Centres were leveraged. Univariable and adjusted multivariable models were used to predict recurrent disease. RESULTS: We identified 326 MOGAD cases (mean age at first event 8.9 years [SD 4.3], 57% female, 77% white and 74% non-Hispanic) and 46% relapsed during a mean follow-up of 3.9 years (SD 4.1). In the adjusted multivariable model, female sex (HR 1.66, 95% CI 1.17 to 2.36, p=0.004) and Hispanic/Latino ethnicity (HR 1.77, 95% CI 1.19 to 2.64, p=0.005) were associated with a higher risk of relapsing MOGAD. Maintenance treatment initiated before a second event with rituximab (HR 0.25, 95% CI 0.07 to 0.92, p=0.037) or intravenous immunoglobulin (IVIG) (HR 0.35, 95% CI 0.14 to 0.88, p=0.026) was associated with lower risk of a second event in multivariable analyses. Conversely, maintenance steroids were associated with a higher estimated relapse risk (HR 1.76, 95% CI 0.90 to 3.45, p=0.097). CONCLUSION: Sex and ethnicity are associated with relapsing MOGAD. Use of rituximab or IVIG therapy shortly after onset is associated with a lower risk of the second event. Preventive treatment after a first event could be considered for those with a higher relapse risk.

Distinct plasma lipids predict axonal injury and multiple sclerosis activity.

BACKGROUND: Lipids are of particular interest for the study of neuroinjury and neuroinflammation as structural lipids are major components of myelin, and a variety of lipid species modulate inflammation. In this study, we performed an in-depth lipidomics analysis to identify lipids associated with injury and disease activity. METHODS: Plasma samples were collected from paediatric-onset multiple sclerosis (MS) cases within 4 years of disease onset from 17 sites. The lipidome was measured using untargeted and targeted mass spectrometry. For cross-sectional analyses, the agreement between multiple machine learning models was used to predict neurofilament light chain (NfL) levels. In longitudinal analyses, the association between clinical (relapse count) and imaging (MRI count with ≥1 enhancing or new T2 lesion) outcomes with each metabolite was estimated using adjusted negative binomial regression. RESULTS: At sample collection, 68% of the 435 included individuals were treatment-naive, with a median disease duration of 0.8 years (IQR 0.3-1.7). For longitudinal analyses, 381 and 335 subjects had at least 1 year of clinical and imaging follow-up, respectively. In cross-sectional analyses, NfL chain levels identified structural lipids (phosphatidylcholines and phosphatidylethanolamines) as the highest-performing predictors, including external validation. In contrast, longitudinal analyses found polyunsaturated fatty acids (PUFAs) and their derivatives to be protective from subsequent disease activity (q<0.001, multiple outcomes). CONCLUSION: There are two categories of lipids associated with MS processes. First, structural lipids strongly associated with NfL levels may result from cell lysis secondary to acute inflammation. In contrast, PUFAs, especially ω-3, had a protective effect on subsequent disease activity.

Patient and family views on research priorities and design of clinical trials and research studies in pediatric multiple sclerosis.

BACKGROUND AND OBJECTIVES: This survey study aimed to (1) identify patient/family research priorities in pediatric-onset multiple sclerosis (POMS), and (2) delineate optimized methods for research study/clinical trials design, engagement, and implementation. METHODS: Participants were as follows: (1) parents of a child (<18 years) with POMS enrolled in a national registry, (2) adolescents (13-17 years) with POMS in the registry, and (3) adults (18-40 years) with POMS receiving care at a registry affiliated clinic. Of 293 eligible participants, 192 completed surveys. RESULTS: Experiences with health care and medications were generally positive but there remain areas of priority improvement. Incentives to participate in clinical trials included medications previously tested and in pill form, bloodwork/study visits required ⩾ every 3 months, cognitive testing ⩽1 hour, compensation for travel and time, ability to continue current multiple sclerosis (MS) medication, option to take study medication if on placebo, and individualized study feedback. Priorities for clinical research were (1) psychosocial impact, (2) cognitive/academic impact, (3) environmental risk, and (4) nutrition. CONCLUSIONS: Results highlighted the importance of a holistic approach to study design and a focus on the impact of disease on daily life to best engage patients and families in POMS clinical trials and research.

Gene-environment interactions: Epstein-Barr virus infection and risk of pediatric-onset multiple sclerosis.

BACKGROUND AND OBJECTIVE: Prior Epstein-Barr virus (EBV) infection is associated with an increased risk of pediatric-onset multiple sclerosis (POMS) and adult-onset multiple sclerosis (MS). It has been challenging to elucidate the biological mechanisms underlying this association. We examined the interactions between candidate human leukocyte antigen (HLA) and non-HLA variants and childhood EBV infection as it may provide mechanistic insights into EBV-associated MS. METHODS: Cases and controls were enrolled in the Environmental and Genetic Risk Factors for Pediatric MS study of the US Network of Pediatric MS Centers. Participants were categorized as seropositive and seronegative for EBV-viral capsid antigen (VCA). The association between prior EBV infection and having POMS was estimated with logistic regression. Interactions between EBV serostatus, major HLA MS risk factors, and non-HLA POMS risk variants associated with response to EBV infection were also evaluated with logistic regression. Models were adjusted for sex, age, genetic ancestry, and the mother's education. Additive interactions were calculated using relative risk due to interaction (RERI) and attributable proportions (APs). RESULTS: A total of 473 POMS cases and 702 controls contributed to the analyses. Anti-VCA seropositivity was significantly higher in POMS cases compared to controls (94.6% vs 60.7%, p < 0.001). There was evidence for additive interaction between childhood EBV infection and the presence of the HLA-DRB1*15 allele (RERI = 10.25, 95% confidence interval (CI) = 3.78 to 16.72; AP = 0.61, 95% CI = 0.47 to 0.75). There was evidence for multiplicative interaction (p < 0.05) between childhood EBV infection and the presence of DRB1*15 alleles (odds ratio (OR) = 3.43, 95% CI = 1.06 to 11.07). Among the pediatric MS variants also associated with EBV infection, we detected evidence for additive interaction (p = 0.02) between prior EBV infection and the presence of the GG genotype in risk variant (rs2255214) within CD86 (AP = 0.30, 95% CI = 0.03 to 0.58). CONCLUSION: We report evidence for interactions between childhood EBV infection and DRB1*15 and the GG genotype of CD86 POMS risk variant. Our results suggest an important role of antigen-presenting cells (APCs) in EBV-associated POMS risk.

Association of nutritional intake with clinical and imaging activity in pediatric multiple sclerosis.

BACKGROUND: Understanding nutrition's role in multiple sclerosis (MS) can guide recommendations and intervention-based studies. OBJECTIVE: Evaluate the association between nutrition and pediatric-onset MS outcomes. METHODS: Prospective longitudinal multicenter study conducted as part of the US Network of Pediatric MS centers. Predictors were collected using a food screener estimating intake of various dietary food groups (e.g. dairy and fruits) and additional calculated indices (e.g. Healthy Eating Index (HEI)). Outcomes included time-from-enrollment to clinical relapse, new magnetic resonance imaging (MRI) T2 lesions, and Expanded Disability Status Scale (EDSS) increase. RESULTS: 353 children with MS were enrolled (mean ± SD age 15.4 ± 2.9, follow-up 3.9 ± 2.6 years). Multivariable analysis demonstrated that increased dairy by 50% of recommended intake was associated with increased relapse risk by 41% (adjusted hazard ratio (HR) 1.41, 95% CI 1.07-1.86), and risk of T2 progression by 40% (1.40, 1.12-1.74). Increased intake of fruit or vegetable above recommended, and every five-point HEI increase decreased relapse risk by 25% (0.75, 0.60-0.95), 45% (0.55, 0.32-0.96), and 15% (0.84, 0.74-0.96), respectively. No associations were found with EDSS. CONCLUSION: This work supports the influence of dietary intake on MS course, particularly with dairy intake. Future prospective study is required to establish causation.

An exploration into the relationship between insomnia and repetitive negative thinking among cancer survivors.

OBJECTIVE: Insomnia and repetitive negative thinking (RNT) are both prevalent among cancer survivors, yet little work has investigated their interrelationship. To explore the hypothesis that RNT and insomnia are related, we conducted secondary analyses on data from a pilot clinical trial of cognitive behavioral therapy for insomnia (CBT-I) for cancer survivors. METHODS: This study analyzed survey data from 40 cancer survivors with insomnia who participated in a pilot randomized trial of CBT-I. Correlations and linear regression models were used to determine associations between aspects of RNT and related constructs (fear of cancer recurrence [FCR], cancer-specific rumination, worry, and intolerance of uncertainty) and sleep (insomnia and sleep quality), while accounting for psychiatric symptoms such as anxiety and depression. Treatment-related change in RNT was examined using a series of linear mixed models. RESULTS: Evidence for an association between RNT and insomnia among cancer survivors emerged. Higher levels of FCR and cancer-related rumination were correlated with more severe insomnia symptoms and worse sleep quality. Notably, FCR levels predicted insomnia, even after controlling for anxiety and depression. Results identified potential benefits and limitations of CBT-I in addressing RNT that should be examined more thoroughly in future research. CONCLUSIONS: RNT is a potential target to consider in insomnia treatment for cancer survivors.

ZSCAN1 Autoantibodies Are Associated with Pediatric Paraneoplastic ROHHAD.

OBJECTIVE: Rapid-onset Obesity with Hypothalamic Dysfunction, Hypoventilation and Autonomic Dysregulation (ROHHAD), is a severe pediatric disorder of uncertain etiology resulting in hypothalamic dysfunction and frequent sudden death. Frequent co-occurrence of neuroblastic tumors have fueled suspicion of an autoimmune paraneoplastic neurological syndrome (PNS); however, specific anti-neural autoantibodies, a hallmark of PNS, have not been identified. Our objective is to determine if an autoimmune paraneoplastic etiology underlies ROHHAD. METHODS: Immunoglobulin G (IgG) from pediatric ROHHAD patients (n = 9), non-inflammatory individuals (n = 100) and relevant pediatric controls (n = 25) was screened using a programmable phage display of the human peptidome (PhIP-Seq). Putative ROHHAD-specific autoantibodies were orthogonally validated using radioactive ligand binding and cell-based assays. Expression of autoantibody targets in ROHHAD tumor and healthy brain tissue was assessed with immunohistochemistry and mass spectrometry, respectively. RESULTS: Autoantibodies to ZSCAN1 were detected in ROHHAD patients by PhIP-Seq and orthogonally validated in 7/9 ROHHAD patients and 0/125 controls using radioactive ligand binding and cell-based assays. Expression of ZSCAN1 in ROHHAD tumor and healthy human brain tissue was confirmed. INTERPRETATION: Our results support the notion that tumor-associated ROHHAD syndrome is a pediatric PNS, potentially initiated by an immune response to peripheral neuroblastic tumor. ZSCAN1 autoantibodies may aid in earlier, accurate diagnosis of ROHHAD syndrome, thus providing a means toward early detection and treatment. This work warrants follow-up studies to test sensitivity and specificity of a novel diagnostic test. Last, given the absence of the ZSCAN1 gene in rodents, our study highlights the value of human-based approaches for detecting novel PNS subtypes. ANN NEUROL 2022;92:279-291.

Characteristics of pediatric patients with multiple sclerosis and related disorders infected with SARS-CoV-2.

BACKGROUND: Pediatric patients with multiple sclerosis (POMS) and related disorders, clinically isolated syndrome (CIS), myelin oligodendrocyte glycoprotein antibody disorder (MOGAD), and neuromyelitis optica spectrum disorder (NMOSD), are commonly treated with immunosuppressants. Understanding the impact of SARS-CoV-2 infection in patients may inform treatment decisions. OBJECTIVE: Characterize SARS-CoV-2 infection prevalence and severity among a cohort of patients with POMS and related disorders, as well as the impact of disease-modifying therapies (DMTs). METHODS: POMS and related disorders patients enrolled in a large, prospective registry were screened for COVID-19 during standard-of-care neurology visits. If confirmed positive of having infection, further analysis was undertaken. RESULTS: Six hundred and sixty-nine patients were surveyed between March 2020 and August 2021. There were 73 confirmed COVID-19 infections. Eight of nine hospitalized patients (89%), and all patients admitted to the ICU were treated with B cell depleting therapy. The unadjusted odds ratio of hospitalization among those who tested positive of having had COVID-19 was 15.27 among those on B-cell-depleting therapy (p = 0.016). CONCLUSIONS: B-cell-depleting treatment was associated with a higher risk of COVID-19, higher rates of hospitalization, and ICU admission, suggesting this therapy carries a higher risk of severe infection in POMS and related disorders.

A new look at cognitive functioning in pediatric MS.

OBJECTIVE: Cognitive involvement in pediatric multiple sclerosis (MS) relative to adult MS is less defined. This study advances our understanding by measuring cognitive performances in pediatric MS, adult MS, and pediatric healthy controls. METHODS: Consecutive relapsing pediatric MS participants from the United States Network of Pediatric MS Centers were compared with pediatric healthy controls and adults with relapsing MS. Participants were compared on two screening batteries: the Brief International Cognitive Assessment for MS and the Cogstate Brief Battery. Results were transformed to age-normative z scores. RESULTS: The pediatric groups (MS vs. Healthy Controls) did not differ on either battery's composite mean score or individual test scores (ps > 0.32), nor in the proportions impaired on either battery, Brief International Cognitive Assessment for MS (26% vs. 24%, p = 0.83); Cogstate Brief Battery (26% vs. 32%, p = 0.41). The pediatric versus adult MS group even after controlling for differences in disease duration performed better on the Brief International Cognition Assessment for MS composite (p = 0.03), Symbol Digit Modalities Test (p = 0.02), Rey Auditory Verbal Learning Test (p = 0.01), and Cogstate choice reaction time (p < 0.001). CONCLUSION: Pediatric MS patients do not differ from healthy pediatric controls on cognitive screens but perform better than adults with MS.

A Single Stage Composite Cleft Septorhinoplasty for Correction of the Mature Unilateral Cleft Nose Deformity - The Gujrat Technique.

OBJECTIVE: To evaluate the results of a single stage composite cleft septorhinoplasty procedure ("The Gujrat Technique") to correct the exaggerated cleft nose deformity after completion of nasal growth in an adult patient cohort. METHODS: Adult patients with a residual unilateral cleft nasal deformity were deemed eligible for the proposed "Gujrat Technique". Over a 10-year period (2007-2017), 96 adult patients underwent this composite cleft septorhinoplasty as a single stage operation. Post-operative nasal symmetry evaluation was undertaken using the validated computer program 'SymNose'. Functional outcome and patient satisfaction were assessed using Nasal Obstruction Symptom Evaluation scale and Rhinoplasty Outcome Evaluation (ROE) questionnaires respectively. Various statistical analysis methods were used to validate the obtained results. RESULTS: Due to poor compliance with follow-up, post-operative assessments were undertaken in only 32 patients. The single group study design using the non-parametric matching pairs Wilcoxon Sign test (p < 0.001) showed overall good to excellent functional and aesthetic outcomes and higher scores of the digital SymNose grading system. There was a significant improvement in ROE scores (from 26.4 ± 2.9 to 85.9 ± 4.7, p < 0.001). There were no major complications or revisions needed in our series. CONCLUSION: The individual components of "The Gujrat Technique" are not novel but their combination in this adult unilateral cleft rhinoplasty cohort has demonstrated a high patient satisfaction with its aesthetic appeal and functional versatility. In the background of limited resources and unpredictable patient follow up, the simplicity, reproducibility and cost effectiveness of this technique make it a practical reconstructive option.

The Survivorship Sleep Program (SSP): A synchronous, virtual cognitive behavioral therapy for insomnia pilot program among cancer survivors.

BACKGROUND: For cancer survivors, insomnia is prevalent, distressing, and persists for years if unmanaged. Cognitive behavioral therapy for insomnia (CBT-I) is an effective treatment yet can be difficult to access and may require modification to address survivorship-specific barriers to sleep. In this 2-phase study, the authors adapted and assessed the feasibility, acceptability, and preliminary effects of synchronous, virtual CBT-I adapted for cancer survivors (the Survivorship Sleep Program [SSP]). METHODS: From April to August 2020, cancer survivors with insomnia (N = 10) were interviewed to refine SSP content and delivery. From October 2020 to March 2021, 40 survivors were recruited for a randomized controlled trial comparing 4 weekly SSP sessions with enhanced usual care (EUC) (CBT-I referral plus a sleep hygiene handout). Feasibility and acceptability were assessed by enrollment, retention, attendance, fidelity, survey ratings, and exit interviews. Insomnia severity (secondary outcome), sleep quality, sleep diaries, and fatigue were assessed at baseline, postintervention, and at 1-month follow-up using linear mixed models. RESULTS: The SSP included targeted content and clinician-led, virtual delivery to enhance patient centeredness and access. Benchmarks were met for enrollment (56% enrolled/eligible), retention (SSP, 90%; EUC, 95%), attendance (100%), and fidelity (95%). Compared with EUC, the SSP resulted in large, clinically significant improvements in insomnia severity (Cohen d = 1.19) that were sustained at 1-month follow-up (Cohen d = 1.27). Improvements were observed for all other sleep metrics except sleep diary total sleep time and fatigue. CONCLUSIONS: Synchronous, virtually delivered CBT-I targeted to cancer survivors is feasible, acceptable, and seems to be efficacious for reducing insomnia severity. Further testing in larger and more diverse samples is warranted.

RCL1 copy number variants are associated with a range of neuropsychiatric phenotypes.

Mendelian and early-onset severe psychiatric phenotypes often involve genetic variants having a large effect, offering opportunities for genetic discoveries and early therapeutic interventions. Here, the index case is an 18-year-old boy, who at 14 years of age had a decline in cognitive functioning over the course of a year and subsequently presented with catatonia, auditory and visual hallucinations, paranoia, aggression, mood dysregulation, and disorganized thoughts. Exome sequencing revealed a stop-gain mutation in RCL1 (NM_005772.4:c.370 C > T, p.Gln124Ter), encoding an RNA 3'-terminal phosphate cyclase-like protein that is highly conserved across eukaryotic species. Subsequent investigations across two academic medical centers identified eleven additional cases of RCL1 copy number variations (CNVs) with varying neurodevelopmental or psychiatric phenotypes. These findings suggest that dosage variation of RCL1 contributes to a range of neurological and clinical phenotypes.

Gene-environment interactions increase the risk of pediatric-onset multiple sclerosis associated with ozone pollution.

BACKGROUND: We previously reported a relationship between air pollutants and increased risk of pediatric-onset multiple sclerosis (POMS). Ozone is an air pollutant that may play a role in multiple sclerosis (MS) pathoetiology. CD86 is the only non-HLA gene associated with POMS for which expression on antigen-presenting cells (APCs) is changed in response to ozone exposure. OBJECTIVES: To examine the association between county-level ozone and POMS, and the interactions between ozone pollution, CD86, and HLA-DRB1*15, the strongest genetic variant associated with POMS. METHODS: Cases and controls were enrolled in the Environmental and Genetic Risk Factors for Pediatric MS study of the US Network of Pediatric MS Centers. County-level-modeled ozone data were acquired from the CDC's Environmental Tracking Network. Participants were assigned ozone values based on county of residence. Values were categorized into tertiles based on healthy controls. The association between ozone tertiles and having MS was assessed by logistic regression. Interactions between tertiles of ozone level and the GG genotype of the rs928264 (G/A) single nucleotide polymorphism (SNP) within CD86, and the presence of DRB1*15:01 (DRB1*15) on odds of POMS were evaluated. Models were adjusted for age, sex, genetic ancestry, and mother's education. Additive interaction was estimated using relative excess risk due to interaction (RERI) and attributable proportions (APs) of disease were calculated. RESULTS: A total of 334 POMS cases and 565 controls contributed to the analyses. County-level ozone was associated with increased odds of POMS (odds ratio 2.47, 95% confidence interval (CI): 1.69-3.59 and 1.95, 95% CI: 1.32-2.88 for the upper two tertiles, respectively, compared with the lowest tertile). There was a significant additive interaction between high ozone tertiles and presence of DRB1*15, with a RERI of 2.21 (95% CI: 0.83-3.59) and an AP of 0.56 (95% CI: 0.33-0.79). Additive interaction between high ozone tertiles and the CD86 GG genotype was present, with a RERI of 1.60 (95% CI: 0.14-3.06) and an AP of 0.37 (95% CI: 0.001-0.75) compared to the lowest ozone tertile. AP results indicated that approximately half of the POMS risk in subjects can be attributed to the possible interaction between higher county-level ozone carrying either DRB1*15 or the CD86 GG genotype. CONCLUSIONS: In addition to the association between high county-level ozone and POMS, we report evidence for additive interactions between higher county-level ozone and DRB1*15 and the CD86 GG genotype. Identifying gene-environment interactions may provide mechanistic insight of biological processes at play in MS susceptibility. Our work suggests a possible role of APCs for county-level ozone-induced POMS risk.

SerpinB1 controls encephalitogenic T helper cells in neuroinflammation.

SerpinB1, a protease inhibitor and neutrophil survival factor, was recently linked with IL-17-expressing T cells. Here, we show that serpinB1 (Sb1) is dramatically induced in a subset of effector CD4 cells in experimental autoimmune encephalomyelitis (EAE). Despite normal T cell priming, Sb1-/- mice are resistant to EAE with a paucity of T helper (TH) cells that produce two or more of the cytokines, IFNγ, GM-CSF, and IL-17. These multiple cytokine-producing CD4 cells proliferate extremely rapidly; highly express the cytolytic granule proteins perforin-A, granzyme C (GzmC), and GzmA and surface receptors IL-23R, IL-7Rα, and IL-1R1; and can be identified by the surface marker CXCR6. In Sb1-/- mice, CXCR6+ TH cells are generated but fail to expand due to enhanced granule protease-mediated mitochondrial damage leading to suicidal cell death. Finally, anti-CXCR6 antibody treatment, like Sb1 deletion, dramatically reverts EAE, strongly indicating that the CXCR6+ T cells are the drivers of encephalitis.

Admixture mapping reveals evidence of differential multiple sclerosis risk by genetic ancestry.

Multiple sclerosis (MS) is an autoimmune disease with high prevalence among populations of northern European ancestry. Past studies have shown that exposure to ultraviolet radiation could explain the difference in MS prevalence across the globe. In this study, we investigate whether the difference in MS prevalence could be explained by European genetic risk factors. We characterized the ancestry of MS-associated alleles using RFMix, a conditional random field parameterized by random forests, to estimate their local ancestry in the largest assembled admixed population to date, with 3,692 African Americans, 4,915 Asian Americans, and 3,777 Hispanics. The majority of MS-associated human leukocyte antigen (HLA) alleles, including the prominent HLA-DRB1*15:01 risk allele, exhibited cosmopolitan ancestry. Ancestry-specific MS-associated HLA alleles were also identified. Analysis of the HLA-DRB1*15:01 risk allele in African Americans revealed that alleles on the European haplotype conferred three times the disease risk compared to those on the African haplotype. Furthermore, we found evidence that the European and African HLA-DRB1*15:01 alleles exhibit single nucleotide polymorphism (SNP) differences in regions encoding the HLA-DRB1 antigen-binding heterodimer. Additional evidence for increased risk of MS conferred by the European haplotype were found for HLA-B*07:02 and HLA-A*03:01 in African Americans. Most of the 200 non-HLA MS SNPs previously established in European populations were not significantly associated with MS in admixed populations, nor were they ancestrally more European in cases compared to controls. Lastly, a genome-wide search of association between European ancestry and MS revealed a region of interest close to the ZNF596 gene on chromosome 8 in Hispanics; cases had a significantly higher proportion of European ancestry compared to controls. In conclusion, our study established that the genetic ancestry of MS-associated alleles is complex and implicated that difference in MS prevalence could be explained by the ancestry of MS-associated alleles.

Functional analysis of a de novo variant in the neurodevelopment and generalized epilepsy disease gene NBEA.

Neurobeachin (NBEA) was initially identified as a candidate gene for autism. Recently, variants in NBEA have been associated with neurodevelopmental delay and childhood epilepsy. Here, we report on a novel NBEA missense variant (c.5899G > A, p.Gly1967Arg) in the Domain of Unknown Function 1088 (DUF1088) identified in a child enrolled in the Undiagnosed Diseases Network (UDN), who presented with neurodevelopmental delay and seizures. Modeling of this variant in the Caenorhabditis elegans NBEA ortholog, sel-2, indicated that the variant was damaging to in vivo function as evidenced by altered cell fate determination and trafficking of potassium channels in neurons. The variant effect was indistinguishable from that of the reference null mutation suggesting that the variant is a strong hypomorph or a complete loss-of-function. Our experimental data provide strong support for the molecular diagnosis and pathogenicity of the NBEA p.Gly1967Arg variant and the importance of the DUF1088 for NBEA function.

Real-World Effectiveness of Initial Disease-Modifying Therapies in Pediatric Multiple Sclerosis.

OBJECTIVE: To assess real-world effectiveness of initial treatment with newer compared to injectable disease-modifying therapies (DMTs) on disease activity in pediatric multiple sclerosis (MS) and clinically isolated syndrome (CIS). METHODS: This is a cohort study of children with MS/CIS followed at 12 clinics in the US Network of Pediatric MS Centers, who received initial therapy with newer (fingolimod, dimethyl fumarate, teriflunomide, natalizumab, rituximab, ocrelizumab) or injectable (interferon-ß, glatiramer acetate) DMTs. Propensity scores (PSs) were computed, including preidentified confounders. Relapse rate while on initial DMT was modeled with negative binomial regression, adjusted for PS-quintile. Time to new/enlarging T2-hyperintense and gadolinium-enhancing lesions on brain magnetic resonance imaging were modeled with midpoint survival analyses, adjusted for PS-quintile. RESULTS: A total of 741 children began therapy before 18 years, 197 with newer and 544 with injectable DMTs. Those started on newer DMTs were older (15.2 vs injectable 14.4 years, p = 0.001) and less likely to have a monofocal presentation. In PS-quintile-adjusted analysis, those on newer DMTs had a lower relapse rate than those on injectables (rate ratio = 0.45, 95% confidence interval (CI) = 0.29-0.70, p < 0.001; rate difference = 0.27, 95% CI = 0.14-0.40, p = 0.004). One would need to treat with newer rather than injectable DMTs for 3.7 person-years to prevent 1 relapse. Those started on newer DMTs had a lower rate of new/enlarging T2 (hazard ratio [HR] = 0.51, 95% CI = 0.36-0.72, p < 0.001) and gadolinium-enhancing lesions (HR = 0.38, 95% CI = 0.23-0.63, p < 0.001) than those on injectables. INTERPRETATION: Initial treatment of pediatric MS/CIS with newer DMTs led to better disease activity control compared to injectables, supporting greater effectiveness of newer therapies. Long-term safety data for newer DMTs are required. ANN NEUROL 2020 ANN NEUROL 2020;88:42-55.

Rituximab in patients with pediatric multiple sclerosis and other demyelinating disorders of the CNS: Practical considerations.

Anti-CD20 therapies have established efficacy in the treatment of immune-mediated neurological and non-neurological diseases. Rituximab, one of the first B-cell-directed therapies, is relatively inexpensive compared to newer anti-CD20 molecules, is available in many countries, and has been used off-label in pediatric patients with neuroimmune conditions. The objective of this paper is to describe the experience with rituximab in pediatric multiple sclerosis and other inflammatory immune-mediated disorders of the central nervous system (CNS), and to define a protocol for its use in clinical practice, in particular addressing doses, interval of administration, duration of treatment, and tests to perform at baseline and during follow-up.