Two Cases of Autoimmune Encephalitis with Multiple Anti-neuronal Antibodies

Autoimmune encephalitis(AE)can arise from various etiologies and present with complex clinical manifestations,especially in cases involving multiple anti-neuronal antibodies.This report presents two cases of AE with multiple anti-neuronal antibodies admitted to Ningbo Medical Center Li Huili Hospital on October 9,2020,and March 12,2024.Case 1 is a 15-year-old boy with positive anti-N-methyl-D-aspartate receptor(NMDAR)and anti-metabotropic glutamate receptor 5(mGluR5)antibodies in his serum and cerebrospinal fluid(CSF).Case 2 is a 14-year-old boy with positive NMDAR and myelin oligodendrocyte glycoprotein(MOG)antibodies in his CSF.Patients with AE who have multiple anti-neuronal antibodies present significant diagnostic and therapeutic challenges,warranting close clinical attention.

Development of an Indirect ELISA Using Recombinant Truncated Envelope Glycoprotein for Detection of Antibodies against Japanese Encephalitis Virus

[ Objective] To develop an indirect ELISA assay for detecting antibodies against envelope glycoprotein （ E protein） of Japanese encephalitis virus （JEV）. [ Method] Specific primers were designed according to JEV sequences published in the GenBank. The cDNA of JEV E gene （about 1 000 10p） was amplified by the RT-PCR with the specific primers. After sequencing analysis, the E gene was cloned into pET30a expression vector and expressed in E. coli BL21 （DE3） with the induction of IPTG. After denaturation, purification and renaturation, the recombinant protein was analyzed by the SDS-PAGE and the westem blotting. An indirect ELISA was developed to detect antibodies against JEV. [ Result] The E protein was mainly expressed in inclusion body. With the purified E protein, the indirect ELISA was developed and displayed good specificity, sensitivity and repeatability, [ Conclusion]The developed ELISA using the truncated E protein as antigen is a simple, convenient and rapid serological method for diagnosis, monitoring antibody level and epidemiological investigation of JEV.

Preparation of Polyclonal Antibodies against NS3 Protein of Japanese Encephalitis Virus

Japanese encephalitis （JE） is a central nervous system disease caused by Japanese encephalitis virus （JEV）, which can infect human and a variety of animals and cause irreversible nerve damages. NS3 protein plays an important role in the process of JEV polyprotein hydrolysis, which is essential for JEV replication. Therefore, NS3 protein may be used as a potential drug target to treat Japanese encephalitis. In this study, the pET-28a-NS3 plasmid was successfully constructed and expressed in E. coli BL21 （ DE3 ） under IPTG induction. The molecular weight of the expressed recombinant protein was 55 ku, which was consistent with the expected result. The positive serum was prepared by immunizing BALB/c mice with NS3 protein and identified by indirect immunofluorescence （IFA）. The results showed that there was a fluorescence reaction between the prepared positive serum of NS3 protein and cells infected with JEV.

Survey on Vaccination of Foxes Against Encephalitis

[Objective] This study was conducted to survey the vaccination of foxes against encephalitis in Changli. [Method] A total of 85 fox blood samples were col- lected from four farmers in Changli County. The serum antibody titer against fox encephalitis was detected by enzyme-linked immunosorbent assay （ELISA）. The OD values were measured to determine the presence of CAV-1 antibody in samples. [Result] 93% of the 15 serum samples from Farmer 1, 86% of the 14 serum sam- ples from Farmer 2, 97% of the 30 serum samples from Farmer 3 and 92% of 26 serum samples from farmer 4 were CAV-1 antibody-positive. In summary, among the 85 serum samples from the four farmers, six were CAV-1 antibody-negative, and 79 were CAV-1 antibody-positive, namely 93% of the foxes were successfully immunized. [Conclusion] The results revealed that vaccination against fox encephali- tis in Changli was run well, but the immunization in several foxes should be strengthened.

Inhibition of Japanese Encephalitis Virus Infection by Flavivirus Recombinant E Protein Domain Ⅲ

Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus closely related to the human pathogens including yellow fever virus, dengue virus and West Nile virus. There are currently no effective antiviral therapies for all of the flavivirus and only a few highly effective vaccines are licensed for human use. In this paper, the E protein domain III (DIII) of six heterologous flaviviruses (DENV1-4, WNV and JEV) was expressed in Escherichia coli successfully. The proteins were purified after a solubilization and refolding procedure, characterized by SDS-PAGE and Western blotting. Competitive inhibition showed that all recombinant flavivirus DIII proteins blocked the entry of JEV into BHK-21 cells. Further studies indicated that antibodies induced by the soluble recombinant flavivirus DIII partially protected mice against lethal JEV challenge. These results demonstrated that recombinant flavivirus DIII proteins could inhibit JEV infection competitively, and immunization with proper folding flavivirus DIII induced cross-protection against JEV infection in mice, implying a possible role of DIII for the cross-protection among flavivirus as well as its use in antigens for immunization in animal models.

Anti-leucine-rich glioma inactivated protein 1 encephalitis with sleep disturbance as the first symptom: A case report and review of literature

BACKGROUND Anti-leucine-rich glioma inactivated protein 1(anti-LGI1) encephalitis is an infrequent type of autoimmune encephalitis(AE) characterized by acute or subacute cognitive and psychiatric disturbance, facio-brachial dystonic seizures(FBDSs), and hyponatremia. Anti-LGI1 AE has increasingly been considered a primary form of AE. Early identification and treatment of this disease are clearly very important.CASE SUMMARY Here, we report that a male patient developed severe anti-LGI1 encephalitis, which was initially misdiagnosed as a sleep disturbance. He was hospitalized for epileptic seizures and typical FBDSs half a month after he developed sleep disturbances. LGI1 antibodies were detected in his cerebrospinal fluid and serum(1:100 and 1:3.2, respectively), which led to the diagnosis of classic anti-LGI1 AE. No obvious abnormality was observed on brain computed tomography images. T2-weighted fluid-attenuated inversion recovery and T2-weighted scans of brain magnetic resonance imaging(MRI) showed slightly elevated signals within the left basal ganglia area. No tumor was detected within the brain of this patient using MRI. After hormone and antiepileptic drug treatment, the patient’s symptoms improved significantly.CONCLUSION Anti-LGI1 antibody-associated encephalitis has characteristic clinical manifestations, such as cognitive impairment, psychiatric symptoms, seizures, sleep disorders, hyponatremia, and FBDSs. LGI1 antibodies are present in the serum and/or cerebrospinal fluid, but their production is sensitive to immunosuppressants, and this disease has a relatively good prognosis. In particular, we should be aware of the possibility of anti-LGI1 antibody-associated encephalitis in adolescents with sleep disorders to avoid missed diagnoses and misdiagnoses.

Preliminary observation on treatment of patients with Japanese B encephalitis with monoclonal antibody

The monoclonat antibodies(McAbs)against Japanese B encephalitis virus for clinicaluse were prepared according to the standards of Food and Drug Administration(FDA,USA).Immediately after the diagnosis,the patients were given 10 mg of McAbs(IgG)in normal salineby intravenous drip plus intramuscular injection.The average febrifugal days of the McAb treat-ment group(55 cases),symptomatic treatment group(12 cases),ribavirin treatment group(17cases)and thymus peptides treatment group(7 cases)were 2.86,6.20,7.16 and 9.11d,respec-tively(P【0.05 or P【0.01).It is necessary to take the skin test before use of the McAbs andto give dexamethasone during the McAb treatment.

Discrimination between leucine-rich glioma-inactivated 1 antibody encephalitis and gamma-aminobutyric acid B receptor antibody encephalitis based on ResNet18

This study aims to discriminate between leucine-rich glioma-inactivated 1(LGI1)antibody encephalitis and gammaaminobutyric acid B(GABAB)receptor antibody encephalitis using a convolutional neural network(CNN)model.A total of 81 patients were recruited for this study.ResNet18,VGG16,and ResNet50 were trained and tested separately using 3828 positron emission tomography image slices that contained the medial temporal lobe(MTL)or basal ganglia(BG).Leave-one-out cross-validation at the patient level was used to evaluate the CNN models.The receiver operating characteristic(ROC)curve and the area under the ROC curve(AUC)were generated to evaluate the CNN models.Based on the prediction results at slice level,a decision strategy was employed to evaluate the CNN models’performance at patient level.The ResNet18 model achieved the best performance at the slice(AUC=0.86,accuracy=80.28%)and patient levels(AUC=0.98,accuracy=96.30%).Specifically,at the slice level,73.28%(1445/1972)of image slices with GABAB receptor antibody encephalitis and 87.72%(1628/1856)of image slices with LGI1 antibody encephalitis were accurately detected.At the patient level,94.12%(16/17)of patients with GABAB receptor antibody encephalitis and 96.88%(62/64)of patients with LGI1 antibody encephalitis were accurately detected.Heatmaps of the image slices extracted using gradient-weighted class activation mapping indicated that the model focused on the MTL and BG for classification.In general,the ResNet18 model is a potential approach for discriminating between LGI1 and GABAB receptor antibody encephalitis.Metabolism in the MTL and BG is important for discriminating between these two encephalitis subtypes.

Glutamic acid decarboxylase 65-positive autoimmune encephalitis presenting with gelastic seizure, responsive to steroid: A case report

BACKGROUND Anti-glutamic acid decarboxylase(GAD)antibody is known to cause several autoimmune-related situations.The most known relationship is that it may cause type I diabetes.In addition,it was also reported to result in several neurologic syndromes including stiff person syndrome,cerebellar ataxia,and autoimmune encephalitis.Decades ago,isolated epilepsy associated with anti-GAD antibody was first reported.Recently,the association between temporal lobe epilepsy and anti-GAD antibody has been discussed.Currently,with improvements in examination technique,many more autoimmune-related disorders can be diagnosed and treated easier than in the past.CASE SUMMARY A 44-year-old female Asian with a history of end-stage renal disease(without diabetes mellitus)under hemodialysis presented with diffuse abdominal pain.The initial diagnosis was peritonitis complicated with sepsis and paralytic ileus.Her peritonitis was treated and she recovered well,but seizure attack was noticed during hospitalization.The clinical impression was gelastic seizure with the presentation of frequent smiling,head turned to the right side,and eyes staring without focus;the duration was about 5–10 s.Temporal lobe epilepsy was recorded through electroencephalogram,and she was later diagnosed with anti-GAD65 antibody positive autoimmune encephalitis.Her seizure was treated initially with several anticonvulsants but with poor response.However,she showed excellent response to intravenous methylprednisolone pulse therapy.Her consciousness returned to normal,and no more seizures were recorded after 5 d of intravenous methylprednisolone treatment.CONCLUSION In any case presenting with new-onset epilepsy,in addition to performing routine brain imaging to exclude structural lesion and cerebrospinal fluid studies to exclude common etiologies of infection and inflammation,checking the autoimmune profile has to be considered.In the practice of modern medicine,autoimmune-related disorders are relatively treatable and should not be missed.

Epidemic Japanese B encephalitis combined with contactinassociated protein-like 2 antibody-positive autoimmune encephalitis:A case report

BACKGROUND It is not uncommon to develop viral encephalitis.Epidemic Japanese B encephalitis infection combined with contactin-associated protein-like 2(CASPR-2)antibody-positive autoimmune encephalitis has not been reported at present.In clinical work,we need to consider more options.CASE SUMMARY A 32-year-old male worker presented with headache,fever and call-unresponsive presentation.Complete cranial magnetic resonance image showed symmetrical abnormal signals in bilateral medial temporal lobe,bilateral thalamus and basal ganglia.Improved lumbar puncture showed that cerebrospinal fluid protein and cell count increased significantly.Viral encephalitis was considered,and the patient's consciousness still increased rapidly after antiviral treatment.Further detection of Cerebrospinal fluid Japanese B encephalitis virus Polymerase Chain Reaction positive,serum autoimmune encephalitis antibody showed CASPR-2 antibody positive(1:320),the patient's condition gradually improved after plasma exchange treatment.3 mo later,the serum CASPR-2 antibody was negative and the patient's condition was stable.CONCLUSION This article reports the world’s first case of Epidemic Japanese B encephalitis infection combined with CASPR-2 antibody-positive autoimmune encephalitis,with a view to raising awareness.

Challenges to associate early onset epilepsy with COVID-19 autoimmune encephalitis:A case

BACKGROUND Diagnosis of coronavirus disease 2019(COVID-19)-related neurological events in the pediatric population is challenging.Overlapping clinical picture of children with altered neurological state and inborn errors of metabolism,in addition to the frequency of asymptomatic COVID-19 cases,pose the main challenges for diagnosis.Diagnostic approaches to the onset post-COVID 19 subacute encephalopathy are still troublesome as seronegative autoimmune encephalitis(AIE)is reported.CASE SUMMARY A 27-mo-old boy was admitted for stormy refractory seizure of polymorphic semiology and altered mental status followed by various neuropsychiatric features that were suggestive of AIE.Brain magnetic resonance imaging and cerebrospinal fluid analysis were normal.Neither the immunological assessment,including viral serologies,antinuclear antibodies,autoimmune antibodies(NMDA,AMPA,CASPR2,LG11,GABARB,Hu,Yo,Ri,CV2,PNMA2,SOX1,Titin,amphiphysin,Recoverin),nor the metabolic assessment for lactate and pyruvate showed significant anomaly.Both positive history of COVID-19 infection and the findings of characteristic repetitive extreme delta brush played a key role in the diagnosis of COVID-19-related AIE.A remarkable improvement in the state of the child was noted after two pulse doses of intravenous Veinoglobulin and high dose of intravenous Corticosteroid.CONCLUSION Diagnostic biomarkers for AIE might aid effective treatment.

Structural mechanisms of GABA A receptor autoimmune encephalitis

Autoantibodies targeting neuronal membrane proteins can cause encephalitis,seizures,and severe behavioral abnormalities.While antibodies for several neuronal targets have been identified,structural details on how they regulate function are unknown.Here we determined cryo-electron microscopy structures of antibodies derived from an encephalitis patient bound to theγ-aminobutyric acid type A(GABAA)receptor.

Advancements in pathogenesis studies of Rasmussen’s encephalitis

Rasmussen＇s encephalitis （ RE ） , which was first described by Rasmussen in 1958 , is a rare, dispersed, and progressive neurological syndrome that is characterized by focal epilepsy, unilateral inflammation of the cerebral cortex, progressive hemiplegia and cognitive deterioration. The etiology of this syndrome remains under investigation, and it is hypothesized and widely accepted that RE is a T-cell-mediated autoimmune response. However, the antigenic epitopes and mechanisms are still unknown. The pathological characteristics of RE are cortical inflammation, neuronal loss, and gliosis that are confined to one cere-bral hemisphere. Hemispherectomy remains the only cure for the seizures and cognitive deterioration associated with the disease, but this procedure results in inevitable functional loss in the brain. Compared with surgery, immunomodulatory treatments are expected to cause less neurological deficits, but with limited clinical effect.

Limbic Encephalitis Associated with Anti-y-aminobutyric Acid B Receptor Antibodies： A Case Series from China

Background： Autoimmune encephalitis associated with antibodies against γ-aminobutyric acid B receptor （GABABR） in patients with limbic encephalitis （LE） was first described in 2010. We present a series of klan Chinese patients tbr further clinical refinement. Methods： Serum and cerebrospinal fluid （CSF） samples from patients referred to the program of encephalitis and paraneoplastic syndrome of Peking Union Medical College Hospital were tested with indirect immunofluorescence. Clinical information of patients with anti-GABABR antibody positivity was retrospectively reviewed, and descriptive statistical analysis was performed. Results： All eighteen anti-GABABR antibody-positive cases had limbic syndromes, and electroencephalogram （EEG） or neuroimaging evidence fulfilled the diagnostic criteria of LE. Four patients had additional antibodies against Hu in serum and one had anti-N-methyl-d-aspartate receptor antibody in both sera and CSF. Seventeen （17/18） patients presented with new-onset refractory seizure or status epileptics. Twelve （12/18） patients had memory deficits, 11 （11/18） patients had personality change, 7 （7/18） patients had disturbance of consciousness, and 3 （3/18） patients showed cerebellar dysfunction. One patient with LE had progressive motor and sensory polyneuropathy. Lung cancer was detected in 6 （6/18） patients. Ten （10/18） patients showed abnormality in bilateral or unilateral mediotemporal region on magnetic resonance imaging. Ten （10/18） patients had temporal lobe epileptic activity with or without general slowing on EEG. Seventeen patients received immunotherapy and 15 of them showed neurological improvement. Four patients with lung cancer died within 1-12 months due to neoplastic complications. Conclusions： Our study demonstrates that most Han Chinese patients with anti-GABABR antibody-associated LE have prominent refractory epilepsy and show neurological improvement on immunotherapy. Patients with underlying lung tumor have a relatively poor prognosis. Testing for anti-GABABR antibodies is necessary for patients with possible LE or new-onset epilepsy with unknown etiology.

Decreases in Both the Seroprevalence of Serum Antibodies and Seroprotection against Japanese Encephalitis Virus among Vaccinated Children

The incidence of Japanese encephalitis(JE)has significantly decreased in China due to JE vaccines.In this study,we investigated the post-JE vaccination seroprevalence and protection provided by vaccinated sera against Japanese encephalitis virus(JEV)to elucidate the persistence and waning of antibodies to JEV among JE-SA14-14-2-vaccinated children.A total of 300 serum samples were collected from vaccinated children aged 3-10 years in Zhaotong,Yunnan,China.The seroprevalence of anti-JEV antibodies was determined by enzyme-linked immune sorbent assay and plaque reduction neutralization test.The highest seropositivity of 82%was observed in vaccinated children during the first 0.5-1.5 years after booster vaccination.Then,the seropositivity began to decline and remained lower than the original level observed in the 0.5-1.5-year group.An association was found between the waning of seroprevalence and elapsed time of the post-booster vaccination.Similarly,the neutralizing antibody(nAb)titres gradually decreased over time,and the levels showed a positive correlation with the protective efficacy in mice.This finding suggests that nAbs play an important role in the antiviral process and that the nAb titre is an adequately credible parameter for evaluating the protective efficacy induced by the JE vaccine.Our results provide data that clarify the persistence and waning of antibodies to JEV,which may help elucidate the pathogenesis of JE.

Encephalitis associated with autoantibodies binding toγ-aminobutyric acid-A,γ-aminobutyric acid-B and glycine receptors:immunopathogenic mechanisms and clinical characteristics

Recent,discoveries of neural antibodies have facilitated the diagnosis of immune-mediated,immunotherapy-responsive neurologic disorders.Antibodies that target inhibitory central nervous system receptors,such asγ-aminobutyric acid-B,γ-aminobutyric acid-A,and glycine receptors,disrupt inhibitory regulatory synaptic functions,and lead to neuronal hyperexcitability.The myriad of neurologic,manifestations associated with these antibodies includes seizures,encephalopathy,muscle rigidity and stiffness.This article provides a review of the immunopathogenic mechanisms and the clinical and therapeutic implications of autoimmune encephalitis associated with these antibodies that target inhibitory receptors.

Gamma-aminobutyric-acid-B receptor antibodies in limbic encephalitis with small cell lung cancer

Encephalitis associated with antibodies to gamma-aminobutyric-acid B(GABA-B)is a subgroup of autoimmune synaptic encephalitis with typical features of limbic encephalitis and small cell lung cancer(SCLC).We report a case of anti-GABA-B receptor encephalitis in a 57-year-old man who presented with seizures,memory loss,and abnormal behavior.He developed partially neurological responses to immunotherapy,but refused comprehensive tumor screening.The symptoms were aggravated again 4 months later.Workup showed antibodies to GABA-B receptors and tumor screening revealed SCLC.It highlights the importance of early screening of underlying tumor and anti-tumor treatment in paraneoplastic cases.

Clinical analysis of 3 cases of autoimmune encephalitis with antibodies against the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor

Objective To analyse the clinical features of encephalitis patients with antibodies against the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor(AMPAR).Methods Three anti-AMPAR encephalitis patients diagnosed in Tangdu Hospital, the Air Force Military Medical University between January 2020 and May 2021 were retrospectively reviewed. The clinical symptoms, supplementary examination, treatment options and outcomes with knowledge from literature were summarized in this study.

继发于单纯疱疹病毒脑炎的抗NMDAR和抗GABA_(BR)双阳性自身免疫性脑炎1例报告及文献复习

目的:分析1例单纯疱疹病毒性脑炎(HSVE)继发抗N-甲基-D-天冬氨酸受体(NMDAR)和抗γ-氨基丁酸B型受体(GABA_(BR))双阳性自身免疫性脑炎(AE)患者的临床表现及诊疗经过,以提高临床医生对该类病的认识。方法:收集1例HSVE继发抗NMDAR和抗GABA_(BR)双阳性AE患者的临床资料,对其诊断和治疗经过进行总结,并结合相关文献进行复习。结果:患者,男性,36岁,以头痛起病,随后出现肢体抽搐,并进展为意识障碍。入院后脑脊液常规生化检测异常,脑脊液单纯疱疹病毒1型(HSV-1) IgG抗体阳性,脑脊液和血清NMDAR抗体检测阳性,头部磁共振成像(MRI)检查提示右侧枕叶白质异常信号,诊断为HSVE继发抗NMDAR脑炎。数月后患者出现精神行为异常、认知障碍和睡眠障碍等症状,血清NMDAR抗体和GABA_(BR)抗体均阳性,诊断为HSVE继发抗NMDAR脑炎和抗GABA_(BR)脑炎。给予激素冲击和静脉注射免疫球蛋白(IVIG)治疗后,患者病情好转出院。随访1年,患者精神症状完全消失,遗留轻度认知功能障碍。结论:HSVE抗病毒治疗有效的恢复期患者临床症状再度恶化时,应高度怀疑继发AE的可能,应尽快完善自身免疫性抗体检测,以期早期诊断,早期治疗,以改善患者预后。

脑出血合并多重抗神经元抗体阳性的副肿瘤性自身免疫性脑炎一例

目的 探讨多重抗神经元抗体阳性的副肿瘤性自身免疫性脑炎(AE)的临床特点和诊治。方法 报道1例脑出血合并多重抗神经元抗体阳性的副肿瘤性AE的临床资料,分析、总结其临床特点。结果 老年男性患者,以脑出血起病,后伴随出现低钠血症为主要表现的抗利尿激素分泌不当综合征、精神症状和幻觉等,血清抗体检测显示抗γ-氨基丁酸B型受体(GABABR)抗体、抗神经元核抗体1型(抗Hu抗体)、抗Y染色体性别决定区相关高迁移率超家族1 (SOX1)抗体三重阳性,胸部CT平扫+增强显示肺癌合并多发转移,脑电图显示广泛性慢波,诊断为副肿瘤性自身免疫性脑炎。结论 多重抗体叠加出现可能导致临床特征的叠加或不典型,给早期诊断带来困难;多重抗体叠加出现高度提示肿瘤,且预后较差。组织免疫荧光法(TBA)和细胞免疫双荧光法(CBA)检测方法互补,有利于提高抗体检测的准确性。