Regulatory T Cells Increase After rh-MOG Stimulation in Non-Relapsing but Decrease in Relapsing MOG Antibody-Associated Disease at Onset in Children.

Background: Myelin oligodendrocytes glycoprotein (MOG) antibody-associated disease (MOGAD) represent 25% of pediatric acquired demyelinating syndrome (ADS); 40% of them may relapse, mimicking multiple sclerosis (MS), a recurrent and neurodegenerative ADS, which is MOG-Abs negative. Aims: To identify MOG antigenic immunological response differences between MOGAD, MS and control patients, and between relapsing versus non-relapsing subgroups of MOGAD. Methods: Three groups of patients were selected: MOGAD (n=12 among which 5 relapsing (MOGR) and 7 non-relapsing (MOGNR)), MS (n=10) and control patients (n=7). Peripheral blood mononuclear cells (PBMC) collected at the time of the first demyelinating event were cultured for 48 h with recombinant human (rh)-MOG protein (10 µg/ml) for a specific stimulation or without stimulation as a negative control. The T cells immunophenotypes were analyzed by flow cytometry. CD4+ T cells, T helper (Th) cells including Th1, Th2, and Th17 were analyzed by intracellular staining of cytokines. Regulatory T cells (Tregs, Foxp3+), CD45RA-Foxp3+ Tregs and subpopulation naive Tregs (CD45RA+Foxp3int), effector Tregs (CD45RA-Foxp3high) and non-suppressive Tregs (CD45RA-Foxp3int) proportions were determined. Results: The mean onset age of each group, ranging from 9.9 to 13.8, and sex ratio, were similar between MOGR, MOGNR, MS and control patients as analyzed by one-way ANOVA and Chi-square test. When comparing unstimulated to rh-MOG stimulated T cells, a significant increase in the proportion of Th2 and Th17 cells was observed in MOGAD. Increase of Th17 cells was significant in MOGNR (means: 0.63 ± 0.15 vs. 1.36 ± 0.43; Wilcoxon-test p = 0.03) but not in MOGR. CD4+ Tregs were significantly increased in MOGNR (means: 3.51 ± 0.7 vs. 4.59 ± 1.33; Wilcoxon-test p = 0.046) while they decreased in MOGR. CD45RA-Foxp3+ Tregs were significantly decreased in MOGR (means: 2.37 ± 0.23 vs. 1.99 ± 0.17; paired t-test p = 0.021), but not in MOGNR. MOGR showed the highest ratio of effector Tregs/non suppressive-Tregs, which was significantly higher than in MOGNR. Conclusions: Our findings suggest that CD4+ Th2 and Th17 cells are involved in the pathophysiology of MOGAD in children. The opposite response of Tregs to rh-MOG in MOGNR, where CD4+ Tregs increased, and in MOGR, where CD45RA-Foxp3+ Tregs decreased, suggests a probable loss of tolerance toward MOG autoantigen in MOGR which may explain relapses in this recurrent pediatric autoimmune disease.

Pediatric onset multiple sclerosis: Future challenge for early diagnosis and treatment.

Multiple sclerosis is a major socio-economical burden as it represents the most common cause of non-traumatic neurological disability in young adults [1]. It affects also children with a lower prevalence and incidence but remains a major concern as disability may occur later during their adulthood. Therefore, there is an absolute need for earlier diagnosis and treatment. In this review, we would focus on how these objectives can be achieved.

E.U. paediatric MOG consortium consensus: Part 3 - Biomarkers of paediatric myelin oligodendrocyte glycoprotein antibody-associated disorders.

A first episode of acquired demyelinating disorder (ADS) in children is a diagnostic challenge as different diseases can express similar clinical features. Recently, antibodies against myelin oligodendrocyte glycoprotein (MOG) have emerged as a new ADS biomarker, which clearly allow the identification of monophasic and relapsing ADS forms different from MS predominantly in children. Due to the novelty of this antibody there are still challenges and controversies about its pathogenicity and best technique to detect it. In this manuscript we will discuss the recommendations and caveats on MOG antibody assays, role in the pathogenesis, and additionally discuss the usefulness of other potential new biomarkers in MOG-antibody associated disorders (MOGAD).

E.U. paediatric MOG consortium consensus: Part 5 - Treatment of paediatric myelin oligodendrocyte glycoprotein antibody-associated disorders.

In recent years, the understanding about the different clinical phenotypes, diagnostic and prognostic factors of myelin oligodendrocyte glycoprotein-antibody-associated disorders (MOGAD) has significantly increased. However, there is still lack of evidence-based treatment protocols for acute attacks and children with a relapsing course of the disease. Currently used acute and maintenance treatment regimens are derived from other demyelinating central nervous system diseases and are mostly centre-specific. Therefore, this part of the Paediatric European Collaborative Consensus attempts to provide recommendations for acute and maintenance therapy based on clinical experience and evidence available from mainly retrospective studies. In the acute attack, intravenous methylprednisolone (IVMP) leads to a favourable outcome in the majority of patients and can be followed by tapering of oral steroids up to a maximum of three months to maintain the benefit of acute treatment by suppressing disease activity. Intravenous immunoglobulins (IVIG) and plasmapheresis constitute second-line therapies in case of insufficient response to IVMP. After a first relapse, maintenance treatment should be started in order to prevent further relapses and the possibility of permanent sequelae. Four first-line therapies consisting of rituximab (RTX), azathioprine, mycophenolate mofetil or monthly IVIG have been identified by the consensus group. In case of further relapses despite maintenance treatment, the consensus group recommends treatment escalation with RTX or IVIG, followed by combining those two, and ultimately adding maintenance oral steroids. Many open questions remain which need to be addressed in further international prospective evaluation of MOGAD treatment. This international collaboration is essential to expand the state of current knowledge.

Risk factors for academic difficulties in children with myelin oligodendrocyte glycoprotein antibody-associated acute demyelinating syndromes.

AIM: To describe cognitive abilities through the evaluation of academic difficulties in children with acute demyelinating syndromes (ADS) and myelin oligodendrocyte glycoprotein (MOG) antibodies. METHOD: This was an observational, retrospective study of a French paediatric cohort that included children aged 18 years and younger. Clinical, biological, and imaging data were collected and academic outcome was measured. RESULTS: Seventy-six children were included in the study with a mean (SD) follow-up of 4 years 7 months (6y 4mo). Median age at disease onset was 9 years 1 months (interquartile range=4y 7mo-13y 11mo; 36 females, 40 males). Thirty-six children relapsed and 20 had academic difficulties at the last follow-up. Academic difficulties, as well as deep grey matter and putaminal lesions (p=0.047 and p=0.006 respectively), were significantly more prevalent in children aged 10 years and younger (p=0.02). Using univariate binary regression analysis, we found that age at disease onset of 10 years and younger (odds ratio [OR] 3.72 [95% confidence interval {CI} 1.19-11.64]; p=0.024), acute disseminated encephalomyelitis at disease onset (OR 52.5 [95% CI 5.97-461.4]; p<0.001), and deep grey matter lesions (OR 17.33 [95% CI 3.87-77.72]; p<0.001) were associated with academic difficulties. INTERPRETATION: MOG antibody-associated ADS have distinct clinical and radiological patterns that are age-dependent. Indirect cognitive evaluation through academic difficulties was prevalent in younger children and is associated with specific clinical and magnetic resonance imaging factors that need to be considered earlier on when assessing this patient population.

Simple FISH-based evaluation of spermatic nuclear architecture shows an abnormal chromosomal organization in balanced chromosomal rearrangement carriers.

INTRODUCTION: Interphasic DNA has a constant three-dimensional conformation, which is particularly striking for spermatic DNA, with distinct chromosomal territories and a constant chromosomal conformation. We hypothesized that this organization is fragile, and that an excess or a lack of chromosomal segments could hinder the genomic structure as a whole. METHODS: Five human male chromosomal translocation carriers and five controls were included. Spermatic DNA spatial organization was studied, in both balanced and unbalanced spermatozoa, with two-dimensional fluorescent in situ hybridization (FISH) via analysis of chromosomes not implicated in the cases' translocations, compared to that of normal controls. Two parameters were studied: the distance between the two telomeric ends of chromosome 1, and the area of the chromosomal territories of chromosomes 1 and 17. RESULTS: Sperm FISH analysis of rearrangement carriers revealed changes in the nuclear architecture compared to that of controls. Inter-telomeric distance and chromosomal territories areas were both significantly increased. DISCUSSION: We show that an excess or lack of chromosomal segments can hinder the normal spatial nuclear architecture in sperm. These results show that nuclear architecture is a fragile assembly, and that local chromosomal abnormalities may impact the nucleus as a whole. This suggests a potential avenue for selection of spermatozoa prior to in vitro fertilization, not only in rearrangement carriers but also in the infertile population at large. Furthermore, we suggest that 2D-FISH could possibly be a useful tool in assessing spermatic nuclear organization in a way to evaluate male fertility.

Association of Maternal First Trimester Serum Levels of Free Beta Human Chorionic Gonadotropin and Hypospadias: A Population Based Study.

PURPOSE: Human chorionic gonadotropin stimulates fetal testosterone production and contributes to normal development of male genitalia. Using population based data we hypothesized that differences in maternal free beta human chorionic gonadotropin may be associated with hypospadias. MATERIALS AND METHODS: Data were obtained from the Paris Registry of Congenital Malformations (REMAPAR) (2011 to 2016). The initial study population included 3,172 pregnant women who gave birth to a singleton live born male infant with a congenital malformation. After exclusion of cases with unknown beta human chorionic gonadotropin and those with chromosomal or genetic abnormalities, the study population included 194 boys with isolated hypospadias and 1,075 controls. For cases with operative notes (125) we obtained data on type (proximal/distal) of hypospadias. Using quantile regression we compared median values of multiple of median beta human chorionic gonadotropin measured for first trimester Down syndrome screening (10th to 13th gestational weeks) for overall as well as by type of hypospadias vs controls. We also considered possible effects of placental dysfunction (maternal age, intrauterine growth retardation and preterm births) as potential confounding factors. RESULTS: Overall the median beta human chorionic gonadotropin multiple of median was comparable for women who had an infant with hypospadias vs controls (0.99 vs 0.95, p=0.3). However, proximal hypospadias was associated with a statistically significant higher median multiple of median than distal hypospadias or unspecified (1.49 vs 0.92 vs 1.05, p=0.02). The estimates were comparable after adjustment for placental dysfunction. CONCLUSIONS: Our findings support the hypothesis that an alteration in maternal beta human chorionic gonadotropin levels is associated with hypospadias. However, this association appears to be limited to proximal hypospadias.

Double chromosomal translocation in an infertile man: one-step FISH meiotic segregation analysis and reproductive prognosis.

BACKGROUND: The prevalence of chromosomal translocations is 1/500 in the general population. While in the vast majority of cases, carriers have a normal phenotype; they can present with difficulty conceiving due to the presence of a proportion of unbalanced gametes as a consequence of abnormal chromosomal segregation during meiosis. Since complex translocations involve three or more chromosomes, meiotic segregation leads to a greater number of possible combinations which effectively complicate both their study and therapeutic care. CASE PRESENTATION: We report on the case of a male carrier of a complex homogeneous double Robertsonian translocation: 44, XY, der(13;14)(q10;q10),der(21;22)(q10;q10). We studied his meiotic segregation by FISH on spermatozoa from the initial sample, as well as following discontinuous gradient centrifugation and after incubation in an hypo-osmotic solution. CONCLUSION: We report a method to study in a simple single-step manner the meiotic segregation of double Robertsonian translocations in spermatozoa. Further, our results suggest that reproductive prognosis of affected individuals may be markedly improved by HOST-based sperm selection (HBSS).