Jayne Ness

CNS aquaporin-4 autoimmunity in children.

Background: In adult patients, autoantibodies targeting the water channel aquaporin-4 (AQP4) are a biomarker for a spectrum of CNS inflammatory demyelinating disorders with predilection for optic nerves and spinal cord (neuromyelitis optica [NMO]). Here we describe the neurologic, serologic, and radiographic findings associated with CNS AQP4 autoimmunity in childhood. Methods: A total of 88 consecutive seropositive children were identified through service evaluation for NMO-IgG. Sera of 75 were tested for coexisting autoantibodies. Clinical information was available for 58. Results: Forty-two patients (73%) were non-Caucasian, and 20 (34%) had African ethnicity. Median age at symptom onset was 12 years (range 4–18). Fifty-seven (98%) had attacks of either optic neuritis (n = 48; 83%) or transverse myelitis (n = 45; 78%), or both. Twenty-six (45%) had episodic cerebral symptoms (encephalopathy, ophthalmoparesis, ataxia, seizures, intractable vomiting, or hiccups). Thirty-eight (68%) had brain MRI abnormalities, predominantly involving periventricular areas (in descending order of frequency): the medulla, supratentorial and infratentorial white matter, midbrain, cerebellum, thalamus, and hypothalamus. Additional autoantibodies were detected in 57 of 75 patients (76%), and 16 of 38 (42%) had a coexisting autoimmune disorder recorded (systemic lupus erythematosus, Sjögren syndrome, juvenile rheumatoid arthritis, Graves disease). Attacks were recurrent in 54 patients (93%; median follow-up, 12 months). Forty-three of 48 patients (90%) had residual disability: 26 (54%) visual impairment and 21 (44%) motor deficits (median Expanded Disability Status Scale 4.0 at 12 months). Conclusions: Aquaporin-4 autoimmunity is a distinctive recurrent and widespread inflammatory CNS disease in children.

Clinical features and viral serologies in children with multiple sclerosis: a multinational observational study

BACKGROUND The full spectrum of clinical manifestations and outcome, and the potential importance of regional or demographic features or viral triggers in paediatric multiple sclerosis (MS), has yet to be fully characterised. Our aim was to determine some of these characteristics in children with MS. METHODS 137 children with MS and 96 control participants matched by age and geographical region were recruited in a multinational study. They underwent structured clinical-demographic interviews, review of academic performance, physical examination, disability assessment (MS patients only), and standardised assays for IgG antibodies directed against Epstein-Barr virus, cytomegalovirus, parvovirus B19, varicella zoster virus, and herpes simplex virus. FINDINGS MS was relapsing-remitting at diagnosis in 136 (99%) children. The first MS attack resembled acute disseminated encephalomyelitis (ADEM) in 22 (16%) of the children, most under 10 years old (mean age 7.4 [SD 4.2] years). Children with ADEM-like presentations were significantly younger than were children with polyfocal (11.2 [4.5] years; p<0.0001) or monofocal (12.0 [3.8] years; p=0.0005) presentations. Permanent physical disability (EDSS>or=4.0) developed within 5 years in 15 (13%) of the 120 children for whom EDSS score was available. 23 (17%) had impaired academic performance, which was associated with increasing disease duration (p=0.02). Over 108 (86%) of the children with MS, irrespective of geographical residence, were seropositive for remote EBV infection, compared with only 61 (64%) of matched controls (p=0.025, adjusted for multiple comparisons). Children with MS did not differ from controls in seroprevalence of the other childhood viruses studied, nor with respect to month of birth, sibling number, sibling rank, or exposure to young siblings. INTERPRETATION Paediatric MS is a relapsing-remitting disease, with presenting features that vary by age at onset. MS in children might be associated with exposure to EBV, suggesting a possible role for EBV in MS pathobiology.

Age-Dependent B Cell Autoimmunity to a Myelin Surface Antigen in Pediatric Multiple Sclerosis

Multiple sclerosis (MS) typically manifests in early to mid adulthood, but there is increasing recognition of pediatric-onset MS, aided by improvements in imaging techniques. The immunological mechanisms of disease are largely unexplored in pediatric-onset MS, in part because studies have historically focused on adult-onset disease. We investigated autoantibodies to myelin surface Ags in a large cohort of pediatric MS cases by flow cytometric labeling of transfectants that expressed different myelin proteins. Although Abs to native myelin oligodendrocyte glycoprotein (MOG) were uncommon among adult-onset patients, a subset of pediatric patients had serum Abs that brightly labeled the MOG transfectant. Abs to two other myelin surface Ags were largely absent. Affinity purification of MOG Abs as well as competition of binding with soluble MOG documented their binding specificity. Such affinity purified Abs labeled myelin and glial cells in human CNS white matter as well as myelinated axons in gray matter. The prevalence of such autoantibodies was highest among patients with a very early onset of MS: 38.7% of patients less than 10 years of age at disease onset had MOG Abs, compared with 14.7% of patients in the 10- to 18-year age group. B cell autoimmunity to this myelin surface Ag is therefore most common in patients with a very early onset of MS.

Pediatric multiple sclerosis

Pediatric multiple sclerosis (MS) accounts for up to 5% of all MS cases. Work conducted over the past 5 years has provided new information about the treatment, pathogenesis, demographics, and natural history of this disorder. Genetic and environmental factors seem to exert critical influences on its development. Clinical, MRI and laboratory data from prepubertal and postpubertal children suggest differences between the immune response and/or CNS environment in younger compared with older children and adults with MS. Randomized, controlled treatment trials for pediatric MS have not yet been performed, but therapies used in adult MS have been evaluated in this population, and their use seems to be safe. This article provides a comprehensive review of current knowledge regarding pediatric MS, highlighting new advances in the field.

Combined Tyramide Signal Amplification and Quantum Dots for Sensitive and Photostable Immunofluorescence Detection

Conventional immunofluorescence detection of biologically relevant proteins and antigens in tissue sections is often limited by relatively weak signals that fade rapidly on illumination. We have developed an immunohistochemical protocol that combines the sensitivity of tyramide signal amplification with the photostability of quantum dots to overcome these limitations. This simple method provides a sensitive and stable fluorescence immunohistochemical alternative to standard chromogen detection.

Common viruses associated with lower pediatric multiple sclerosis risk

Background: Because common viruses are encountered during childhood, pediatric multiple sclerosis (MS) offers a unique opportunity to investigate the influence of these viruses on disease susceptibility and the interactions between seroprevalence and select HLA genotypes. We studied seroprevalence for Epstein-Barr virus (EBV), cytomegalovirus (CMV), and herpes simplex virus (HSV) type 1 and HLA-DRB1*1501/1503 status as predictors of pediatric MS. Methods: This was a retrospective analysis of prospectively collected demographic, clinical, and biologic data in subjects up to 18 years of age with early MS, control subjects seen at the same regional referral pediatric MS clinics, and additional healthy pediatric control subjects. Results: Patients with early pediatric MS (n = 189) and pediatric control subjects (n = 66) were tested. Epstein-Barr nuclear antigen-1 seropositivity was associated with an increased odds of MS (odds ratio [OR] 3.78, 95% confidence interval [CI] 1.52–9.38, p = 0.004) in analyses adjusted for age, sex, race, ethnicity, and HLA-DRB1*1501/1503 status. In multivariate analyses including EBV status, a remote infection with CMV (OR 0.27, 95% CI 0.11–0.67, p = 0.004) was associated with a lower risk of developing MS. Although a remote infection with HSV-1 was not associated with an increased odds of MS, a strong interaction was found between HSV-1 status and HLA-DRB1 in predicting MS (p < 0.001). HSV-1 was associated with an increased risk of MS in those without a DRB1*15 allele (OR 4.11, 95% CI 1.17–14.37, p = 0.03), whereas the effect was reversed in those who were DRB1*15-positive (OR 0.07, 95% CI 0.02–0.32, p = 0.001). Conclusions: These findings suggest that some infections with common viruses may in fact lower MS susceptibility. If this is confirmed, the pathways for risk modification remain to be elucidated.

Cognitive Impairment Occurs in Children and Adolescents With Multiple Sclerosis Results From a United States Network

In the largest sample studied to date, we measured cognitive functioning in children and adolescents with pediatric multiple sclerosis (n = 187) as well as those with clinically isolated syndrome (n = 44). Participants were consecutively enrolled from six United States Pediatric Multiple Sclerosis Centers of Excellence. Participants had a mean of 14.8 ± 2.6 years of age and an average disease duration of 1.9 ± 2.2 years. A total of 65 (35%) children with multiple sclerosis and 8 (18%) with clinically isolated syndrome met criteria for cognitive impairment. The most frequent areas involved were fine motor coordination (54%), visuomotor integration (50%), and speeded information processing (35%). A diagnosis of multiple sclerosis (odds ratio = 3.60, confidence interval = 1.07, 12.36, P = .04) and overall neurologic disability (odds ratio = 1.47, confidence interval = 1.10, 2.10, P = .03) were the only independent predictors of cognitive impairment. Cognitive impairment may occur early in these patients, and prompt recognition is critical for their care.

Younger children with MS have a distinct CSF inflammatory profile at disease onset.

Background: The clinical and MRI presentation differs between earlier- and later-onset pediatric multiple sclerosis (MS), whereas the effect of age on the CSF inflammatory profile is unknown and may contribute to delayed diagnosis. Objectives: To compare the CSF cellular and immunoglobulin G (IgG) profiles between earlier- and later-onset pediatric MS. Methods: We queried the databases of 6 pediatric MS centers for earlier-onset (onset <11 years) and later-onset (≥11 and <18 years) patients with MS or clinically isolated syndrome who underwent CSF analysis within the first 3 months of presentation (observational study). We compared CSF white blood cell (WBC) differential count, IgG index, and IgG oligoclonal bands between age groups. Results: We identified 40 earlier-onset (mean age at onset = 7.2 ± 2.7 years, 60% females) and 67 later-onset pediatric MS patients (15.1 ± 1.7 years, 63% females). Although WBC count tended to be higher in earlier-onset patients (median = 9/mm3 [0–343] vs 6 [0–140], p = 0.15), they had a lower proportion of lymphocytes (70% [0–100] vs 93% [0–100] of WBCs, p = 0.0085; difference = +3% per 1-year increase of age, p = 0.0011) and higher proportion of neutrophils than later-onset patients (0.5% [0–75] vs 0% [0–50] of WBCs, p = 0.16; difference = −1% per 1-year increase of age, p = 0.033). In earlier-onset disease, fewer patients had an elevated IgG index than in the later-onset group (35% vs 68% of patients, p = 0.031). Conclusion: Age modifies the CSF profile at pediatric multiple sclerosis (MS) onset, which may mislead the diagnosis. Our findings suggest an activation of the innate rather than the adaptive immune system in the earlier stages of MS or an immature immune response.

Multiple Sclerosis Therapies in Pediatric Patients With Refractory Multiple Sclerosis

BACKGROUND Currently available disease-modifying therapies (DMTs) are known to be only partially effective in adults with multiple sclerosis (MS). Little is known about pediatric patients with MS who experience refractory disease while receiving first-line DMTs. OBJECTIVE To assess the occurrence and management of refractory disease in a group of pediatric patients with MS treated with first-line DMTs approved for adult patients within a network of pediatric MS centers in the United States. DESIGN, SETTING, AND PATIENTS A multicenter, retrospective, longitudinal, open-label study design involving record review of 258 patients with pediatric-onset MS (68.6% female; mean [SD] age at disease onset, 13.2 [3.5] years; range of age at onset, 2.0-17.9 years) who were seen at 6 pediatric MS centers in the United States. INTERVENTION We evaluated medication changes owing to refractory disease in cases of pediatric-onset MS. MAIN OUTCOME MEASURE Disease stability as represented by lack of medication change for breakthrough disease. RESULTS Records of 258 children with a confirmed diagnosis of MS and exposure to DMTs were reviewed. Interferon beta (prescribed to 200 of 258 children [77.5%]) and glatiramer acetate (prescribed to 53 of 258 children [20.5%]) were the 2 most frequently used first-line DMTs. Overall, 144 children (55.8%) continued receiving 1 therapy, while 65 (25.2%), 29 (11.2%), and 20 (7.8%) received 2, 3, or 4 or more sequential therapies, respectively, during a mean (SD) observation period of 3.9 (2.8) years. Second-line DMT use was restricted to interferon beta and glatiramer acetate in 203 children (78.7%), whereas other treatments such as broad-spectrum chemotherapies (cyclophosphamide, mitoxantrone hydrochloride), natalizumab, corticosteroids (monthly), and daclizumab were used at some point during the observation period for disease management in 55 children (21.3%). Hispanic children were more likely to experience breakthrough disease while receiving first-line DMTs than non-Hispanic children. CONCLUSION Although switching between first-line DMTs may be effective in pediatric patients with disease that is refractory to initial treatment, a subset of patients may require second-line therapeutic interventions.

Selective involvement of BH3-only Bcl-2 family members Bim and Bad in neonatal hypoxia–ischemia

Perinatal hypoxic-ischemic injury is a common cause of neurologic disability mediated in part by Bcl-2 family-regulated neuronal apoptosis. The Bcl-2 protein family consists of both pro- (e.g. Bax, Bad, Bid, Bim) and anti-apoptotic (e.g. Bcl-2, Bcl-X(L)) proteins that regulate mitochondrial outer membrane integrity, cytochrome c release and caspase activation. Previous studies have implicated Bax as an important mediator of neuronal death in several models of brain injury, including neonatal hypoxia-ischemia (HI). In this study, we assessed the roles of several members of the pro-apoptotic BH3 domain-only Bcl-2 sub-family in an in vivo mouse model of neonatal HI. Seven-day old control and gene-disrupted mice underwent unilateral left carotid ligation followed by 45 min exposure to 8% oxygen and the extent of brain injury was assessed 2 days later. Following HI, mice deficient in Bad or Bim exhibited reduced activated caspase-3 and glial fibrillary acidic protein immunostaining in their brains compared to similarly treated control animals. Measurement of hippocampal area showed decreased parenchymal loss in both Bad- and Bim-deficient mice versus control animals. In contrast, loss of Bid, another BH3-only protein, provided no protection from neonatal HI brain injury. These results indicate that Bad and Bim are selectively involved in neuron death following neonatal HI and may be targets for therapeutic intervention.