Human-induced pluripotent stem cell-derived cerebral organoid of leukoencephalopathy with vanishing white matter.

INTRODUCTION: Leukoencephalopathy with vanishing white matter (VWM) is a rare autosomal recessive leukoencephalopathy resulting from mutations in EIF2B1-5, which encode subunits of eukaryotic translation initiation factor 2B (eIF2B). Studies have found that eIF2B mutation has a certain influence on embryonic brain development. So far, the effect of the eIF2B mutations on the dynamic process of brain development is not fully understood yet. AIMS: Three-dimensional brain organoid technology has promoted the study of human nervous system developmental diseases in recent years, providing a potential platform for elucidating the pathological mechanism of neurodevelopmental diseases. In this study, we aimed to investigate the effects of eIF2B mutation on the differentiation and development of different nerve cells during dynamic brain development process using 3D brain organoids. RESULTS: We constructed eIF2B mutant and wild-type brain organoid model with induced pluripotent stem cell (iPSC). Compared with the wild type, the mutant brain organoids were significantly smaller, accompanied by increase in apoptosis, which might be resulted from overactivation of unfolded protein response (UPR). Neuronal development was delayed in early stage, but with normal superficial neuronal differentiation in later stage. eIF2B mutations resulted in immature astrocytes with increased expression of GFAPδ, nestin, and αB-crystallin, and there were increased oligodendrocyte progenitor cells, decreased mature oligodendrocytes, and sparse myelin in mutant cerebral organoids in the later stage. CONCLUSION: we constructed the first eIF2B mutant cerebral organoids to explore the dynamic brain development process, which provides a platform for further research on the specific pathogenesis of VWM.

Secretomics Alterations and Astrocyte Dysfunction in Human iPSC of Leukoencephalopathy with Vanishing White Matter.

Leukoencephalopathy with vanishing white matter (VWM) is an inherited leukoencephalopathy characterized by progressive rarefaction of cerebral white matter. Dysfunction of patient astrocyte plays a central role in the pathogenesis, while the immaturity of oligodendrocyte is probably secondary. How eIF2B mutant astrocytes affect the maturation and myelination of oligodendrocyte precursor cells (OPCs) is unclear yet. We used induced pluripotent stem cells (iPSCs) derived from our patient with EIF2B5 mutations to differentiate into astrocytes (AS) and OPCs, and aimed to verify that patient astrocytes inhibited the differentiation of OPCs by abnormalities of secreted proteins. eIF2B mutant astrocytes and astrocyte-conditioned medium (ACM) both inhibited the maturation of OPCs. It was revealed that 13 promising proteins exhibited a similar up- or downregulation by the PRM method correlated well with TMT results. eIF2B mutant astrocytes may secrete abnormal extracellular matrix (HA, LAMA4, BGN, FBN1, VASN, PCOLCE, MFAP4), cytokines (IL-6, CRABP1, ISG15), growth factors (PDGF-AA, CNTF, IGF-II, sFRP1, SERPINF1) and increased FABP7, which might lead to the differentiation and maturation disorder of OPCs. We analyzed the astrocyte-conditioned medium to find the key secretory molecules affecting the differentiation and maturation of OPCs, which provides potential clues for further research on the mechanism of VWM.

Association Between Late-Onset Leukoencephalopathy With Vanishing White Matter and Compound Heterozygous EIF2B5 Gene Mutations: A Case Report and Review of the Literature.

Leukoencephalopathy with vanishing white matter (LVWM) is an autosomal recessive disease. Ovarioleukodystrophy is defined as LVWM in females showing signs or symptoms of gradual ovarian failure. We present a 38-year-old female with ovarioleukodystrophy who showed status epilepticus, gait instability, slurred speech, abdominal tendon hyperreflexia, and ovarian failure. Abnormal EEG, characteristic magnetic resonance, and unreported EIF2B5 compound heterozygous mutations [c.1016G>A (p.R339Q) and c.1157G>A (p.G386D)] were found. Furthermore, the present report summarizes 20 female patients with adult-onset ovarioleukodystrophy and EIF2B5 gene mutations. In conclusion, a new genetic locus for LVWM was discovered. Compared with previous cases, mutations at different EIF2B5 sites might have different clinical manifestations and obvious clinical heterogeneity.

Correlation Between Genotype and Age of Onset in Leukoencephalopathy With Vanishing White Matter.

Purpose: Leukoencephalopathy with vanishing white matter (VWM) is an autosomal recessive leukoencephalopathy caused by mutations in any of the five genes encoding the subunits of eukaryotic translation initiation factor 2B (eIF2B). The severity of the disease varies considerably, and its genotypic-phenotypic correlation is still unclear. Age of onset is the only independent clinical predictor for VWM severity. In this study, the correlation between genotype and age at onset of patients was investigated. Methods: Data were collected from patients with VWM in the available literature reports and from those diagnosed in Peking University First Hospital. The age of onset was divided into early-onset (≤4 years) and late-onset type (>4 years) for the analysis of the correlation between genotype and age of onset in patients with VWM. Results: A total of 341 patients were included, 281 were reported in 87 available articles and 60 were diagnosed in our center. A total of 180 different mutations were found, among which 86.1% were missense. The gene (EIF2B1-5) in which the mutation located, and the number of null alleles were not associated with age of onset in these patients. Certain mutations such as eIF2Bε[Arg195His] and eIF2Bε[Arg269Gln] that were predicted to have a serious influence on eIF2B structure were related to earlier age of onset. EIF2Bγ[Ala87Val] which was predicted to have a minimal influence on eIF2B structure, was related to later age of onset. Whereas eIF2Bß[Glu213Gly], eIF2Bß[Gly200Val] and eIF2Bε[Thr91Ala], also predicted having a small effect on the structure of eIF2B, did not show correlation with the age of onset. The onset age of patients with one or biallelic missense mutations located in the catalytic domain or other homologous domains in catalytic subunits (eIF2Bγ, ε) was earlier than that of patients with biallelic mutations located in the NT domain. Conclusion: The onset age of patients with different genotypes varied greatly. The degree of influence in protein structure of some missense mutations was correlated with phenotypic severity, but the results were not completely consistent. The combined effect of biallelic mutations, the role of regulatory genes, environmental stress and other potential factors on phenotypes need to be further explored.

Relación médico legal de la enfermedad de sustancia blanca evanescente como un estado anterior y su implicación ante el trauma craneoencefálico: reporte de caso / Medical-legal relationship of evanescent white matter disease as a previous state and its implication in the cranioencephalic trauma: case report

Resumen La enfermedad de sustancia blanca representa una enfermedad poco común en usuarios que se apersonan al Organismo de Investigación Judicial, por este motivo al valorar un caso es necesario investigar los antecedentes de la medicina legal para establecer mecanismos causales con hechos representados en la sociedad. Además, es necesario abordar la enfermedad de sustancia blanca desde su aparición, incidencia, aspectos clínicos, hallazgos ante una posible autopsia, explorar el desarrollo de fisiopatología como indagar acerca de las formas de diagnosticar la enfermedad y valorar las opciones terapéuticas. Estos conocimientos son base para establecer una relación médico legal y analizar si el caso de una niña de 9 años tiene correlación con una historia de trauma en cabeza que no evidencia cambios inflamatorios, aumento de volumen de tejidos blandos o duros, excoriaciones, equimosis, hematomas, cicatrices, gradas o callos óseos y con valoraciones médicas que indican tetraparesia flácida en ausencia de hallazgos patológicos al reporte de tomografía axial computarizada y resonancia magnética de columna cervicodorsal.

Abstract White matter disease represents a rare disease in users who go to the Organismo de Investigación Judicial (Judicial Investigation Agency) for this reason, when evaluating a case, it is necessary to investigate the antecedents of legal medicine to establish causal mechanisms with facts represented in society. In addition, it is necessary to address white matter disease from its appearance, incidence, clinical aspects, findings in a possible autopsy, explore the development of pathophysiology such as inquire about ways to diagnose the disease, and assess therapeutic options. This knowledge is the basis for establishing a legal medical relationship and analyzing whether the case of a 9-year-old girl has a correlation with a history of head trauma that does not show inflammatory changes, increased soft or hard tissue volume, excoriations, bruising, bruising. , scars, bleachers or calluses and with medical evaluations that indicate flaccid tetraparesis in the absence of pathological findings on the report of computed tomography and magnetic resonance imaging of the cervicodorsal spine.

Leucoencefalopatia com substância branca evanescente: um relato de caso / Leukoencephalopathy with evanescent white matter: a case report

RESUMO Objetivo: Descrever uma criança diagnosticada com leucoencefalopatia com substância branca evanescente (LSBE), uma doença genética rara que possui padrão de herança autossômico recessivo. Descrição do caso: Criança do sexo masculino, com 5 meses de idade, que mostrava recusa da amamentação e sonolência, começou a apresentar quadro de desidratação, com boca seca, aumento da temperatura corporal e adipsia. Com o passar dos dias, os sintomas agravaram-se. O lactente apresentou-se muito sonolento e foi transferido para a unidade de tratamento intensivo (UTI), onde permaneceu por uma semana. Nesse período, foi identificada, na ressonância magnética de crânio, uma alteração de sinal com predomínio hiperatenuado T2, comprometendo particularmente a substância branca, de aspecto difuso e simétrico. O lactente apresentou crises convulsivas desde então. Aos 11 meses foi diagnosticado com tonsilite, demonstrando quadros recorrentes de picos febris e sonolência excessiva. Na evolução do quadro, o lactente entrou em estado comatoso progredindo a óbito. O diagnóstico de LSBE foi confirmado em exames realizados após o óbito, e tardiamente foi identificada uma doença genética decorrente de mutações em um dos cinco genes que são responsáveis pela codificação do complexo fator de iniciação da tradução de eucariontes 2B (eIF2B), envolvido com o controle da tradução de proteínas, sendo descrita como patogênica em indivíduos com LSBE. Comentários: A LSBE é uma doença cerebral hereditária com início na infância. A doença apresenta-se de maneira crônica e progressiva, com episódios adicionais de rápida deterioração, como evidenciado no presente relato de caso.

ABSTRACT Objective: To describe the case of a child diagnosed with leukoencephalopathy with vanishing white matter (LVWM), a rare genetic disease with autosomal recessive inheritance pattern. Case description: A 5-month-old male child started to refuse breast-feeding, showing somnolence and signs of dehydration,with dry mouth, increasing body temperature and adipsy. As days went by, the symptoms got worse. The infant was very sleepy and was transferred to the intensive care unit, where he stayed for one week. At this time, a signal alteration with hyper attenuated T2 predominance was identified in the magnetic resonance imaging, compromising the white matter, which had diffuse and symmetrical aspect. At this time, the infant started to present seizures. When the infant was 11 months old, he was diagnosed with tonsillitis and presented recurrent fever peaks and extreme sleepiness. After hospital admission, the infant progressed to a comatose state and died. The diagnosis of LVWM was confirmed in examinations performed after death. As a late diagnosis, a genetic disease was identified with a mutation in one of the five genes responsible for the codification of complex eukaryotic translation initiation factor 2B (eIF2B), involved with the control of the protein translation and which is described as pathogenic in individuals with LVWM. Comments: LVWM is a hereditary brain disease that occurs primarily in children. The disease is chronic and progressive, with additional episodes of rapid deterioration, as shown in the present case report.

The clinical and genetic features of a case with antenatal form of leukoencephalopathy with vanishing white matter disease / 临床儿科杂志

Objective To explore the clinical features and gene mutations of antenatal form leukoencephalopathy with vanishing white matter disease (VWM).Methods The clinical data and genetic test results in a patient with antenatal form of VWM were retrospectively analyzed.Results A three months old patient was admitted to our hospital with intermittent convulsions commenced from the first month after birth.The baby had low birth weight (1900g) and asphyxia at birth.Developmental retardation and cataracts in both eyes were found on physical examination,and the patient couldn't stare,gaze-following,be amused and raise his head.In addition,he showed hypermyotonia of both lower extremities.Diffused and symmetrical abnormal signals same as that of the cerebrospinal fluid in the cerebral white matter were observed by brain CT and MRI scanning,and the lesions were gradually enlarged.Moreover,a missense mutation (c.1016G＞A) and a frameshift mutation (c.1809delC) in EIF2B5 gene inherited from his parent were detected by DNA sequencing.Conclusions VWM is one of the most prevalently inherited childhood white matter disorders,but the case of antenatal form is very rare.The diagnosis should be based on clinical manifestations and EIF2B genetic analysis.To our knowledge,the frameshift mutation c.1809delC has never been reported to date.

Eukaryotic translation initiation factor 2B and leukoencephalopathy with vanishing white matter / 北京大学学报(医学版)

Leukoencephalopathy with vanishing white matter(VWM) is one of the most prevalent inherited white matter disorders in childhood,and it′s the only known hereditary human disease due to the direct defects in protein synthesis process,with the gene defects in EIF2B1-5,encoding the five subunits of eukaryotic translation initiation factor(eIF2B ?,?,?,? and ?) respectively.eIF2B is essential for the protein translation initiation process,and its action is realized via eukaryotic translation initiation factor2(eIF2).Phosphorylation of eIF2? and eIF2B? is an important way to regulate eIF2B function,and thus play a key role in control of the protein translation level under physiological condition.Mutant eIF2B results in functional defects and decrease of the overall protein translation in cells,but in increase the translation of proteins with multiple upstream open reading frames,such as activating transcription factor 4(AFT4),which leads to the susceptibility to un-folded protein response under stress,and the following apoptosis.The exact pathogenic mechanisms of VWM are far from well understood.It′s suggested that level of AFT4 in cells with eIF2B mutations is higher than in wild type cells under physiological condition,which makes the mutant cells more susceptible to endoplasmic reticulum(ER) stress and unfolded protein response(UPR).Under stress,the defect eIF2B leads to a vicious cycle of UPR activation,which may underlie the neurological aggravation in VWM patients after minor stress,a specific cli-nical feature of VWM.Elucidating the pathogenesis of VWM will be helpful to further understand the protein translation process in eukaryotic cells,and provide a clue for possible therapeutic targets and treatment strategies in the future.Abstract:SUMM ARY Leukoencephalopathy with vanishing white matter(VWM) is one of the most prevalent in-herited white matter d isorders in childhood,and i′ts the only known hered itary human d isease due to the d irect defects in protein synthesis process,with the gene defects inEIF2B1-5,encod ing the five sub-units of eukaryotic translation initiation factor(eIF2B?,?,?,?and?) respectively.eIF2B is essential for the protein translation initiation process,and its action is realized via eukaryotic translation initiation factor2(eIF2).Phosphorylation of eIF2?and eIF2B?is an important way to regulate eIF2B function,and thus play a key role in control of the protein translation level under physiological cond ition.Mutant eIF2B results in functional defects and decrease of the overall protein translation in cells,but in increase the translation of proteins with multiple upstream open read ing frames,such as activating transcription factor 4(AFT4),which leads to the susceptibility to un-folded protein response under stress,and the following apoptosis.The exact pathogenic mechanisms ofVWM are far from well understood.I′ts sugges-ted that level ofAFT4 in cells with eIF2B mutations is higher than in wild type cells under physiological cond ition,which makes the mutant cellsmore susceptible to endoplasm ic reticulum(ER) stress and un-folded protein response(UPR).Under stress,the defect eIF2B leads to a vicious cycle ofUPR activa-tion,which may underlie the neurological aggravation in VWM patients afterm inor stress,a specific cli-nical feature ofVWM.E lucidating the pathogenesis ofVWM will be helpful to further understand the pro-tein translation process in eukaryotic cells,and provide a clue for possible therapeutic targets and treat-ment strategies in the future.