Dissecting the Role of Anti-ganglioside Antibodies in Guillain-Barré Syndrome: an Animal Model Approach

Distribution characteristics of antinuclear antibodies in Guillain-Barré syndrome and its relationship with disease severity

BACKGROUND

Guillain-Barré syndrome (GBS), an acquired immune-mediated autoimmune disorder affecting the peripheral nervous system (PNS), is associated with autoimmunity. The presence of autoantibodies in the blood is an important feature of autoimmune diseases. Herein, we explored the distribution characteristics of the antinuclear antibodies (ANAs) in GBS and the correlation between ANAs and disease severity.

MATERIALS AND METHODS

We retrospectively analyzed the clinical data of 170 GBS patients. According to ANAs, GBS patients were divided into ANAs positive and negative groups. The clinical characteristics of these two groups were compared. The distribution difference was also compared between male and female GBS patients. In addition, all enrolled patients were divided into more severe group and milder group according to whether the Hughes score at nadir ≥ 3 or not. Gender, age, and ANAs were compared between the two groups.

RESULTS

In this study, the positive rate of ANAs was 27.1 % in 170 GBS patients, among which anti-SSA-52/Ro52 antibody and antimitochondrial antibody M2 made up the largest proportion. In the ANAs positive group, GBS patients had longer days of hospitalization, more respiratory function involvement, and higher level of CSF IgG than the ANAs negative group. Compared to the ANAs negative group, Medical Research Council (MRC) scores on admission and at nadir were lower, and Hughes functional Grading Scale (HFGS) scores on admission and at nadir were higher in GBS patients with ANAs positive group. Erasmus GBS Respiratory Insufficiency Score (EGRIS) in ANAs positive GBS patients group was significantly higher than ANAs negative group. Gender had no effects on the distribution of ANAs in GBS patients. Moreover, we found that the anti-SSA-60 antibodies and age were positively correlated with GBS severity. In addition, in the anti-SSA-60 antibody positive group, GBS patients had longer days of hospitalization, more respiratory function involvement, higher HFGS scores on admission/at nadir, and lower MRC scores at nadir compared with the anti-SSA-60 antibody negative group.

CONCLUSION

Anti-SSA-52/Ro52 antibody and antimitochondrial antibody M2 were the most common ANAs in GBS patients. Anti-SSA-60 antibodies and age positively correlated with GBS severity. Positive anti-SSA-60 antibodies and age were independent predictors of GBS patient severity.

Potential clinical implications of molecular mimicry-induced autoimmunity

BACKGROUND

Molecular mimicry is hypothesized to be a mechanism by which autoimmune diseases are triggered. It refers to sequence or structural homology between foreign antigens and self-antigens, which can activate cross-reactive lymphocytes that attack host tissues. Elucidating the role of molecular mimicry in human autoimmunity could have important clinical implications.

OBJECTIVE

To review evidence for the role of molecular mimicry in major autoimmune diseases and discuss potential clinical implications.

METHODS

Comprehensive literature review of clinical trials, observational studies, animal models, and immunology studies on molecular mimicry in multiple sclerosis, type 1 diabetes, rheumatoid arthritis, lupus, Guillain-Barre syndrome, autoimmune myocarditis, and primary biliary cirrhosis published from 2000-2023.

RESULTS

Substantial indirect evidence supports molecular mimicry as a contributor to loss of self-tolerance in several autoimmune conditions. Proposed microbial triggers include Epstein-Barr virus, coxsackievirus, Campylobacter jejuni, and bacterial commensals. Key mechanisms involve cross-reactive T cells and autoantibodies induced by epitope homology between microbial and self-antigens. Perpetuation of autoimmunity involves epitope spreading, inflammatory mediators, and genetic factors.

CONCLUSIONS

Molecular mimicry plausibly explains initial stages of autoimmune pathogenesis induced by infection or microbiota disturbances. Understanding mimicry antigens and pathways could enable improved prediction, monitoring, and antigen-specific immunotherapy for autoimmune disorders. However, definitive proof of causation in humans remains limited. Further research should focus on establishing clinical evidence and utility.

Current status of Guillain-Barré syndrome (GBS) in China: a 10-year comprehensive overview

Guillain-Barré syndrome (GBS) is an acute inflammatory polyradiculoneuropathy; a disease involving the peripheral nervous system which is the most common cause of acute flaccid paralysis worldwide. So far, it is still lack of a comprehensive overview and understanding of the national epidemiological, clinical characteristics, and the risk factors of GBS in China, as well as differences between China and other countries and regions in these respects. With the global outbreak of the coronavirus disease 2019 (COVID-19), an epidemiological or phenotypic association between severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection and GBS has attracted great attention. In this review, we outlined the current clinical data of GBS in China by retrieving literature, extracting and synthesizing the data of GBS in China from 2010 to 2021. Besides, we compared the characteristics of epidemiology, preceding events and clinical profiles of GBS between China and other countries and regions. Furthermore, in addition to conventional intravenous immunoglobulin (IVIG) and plasma exchange (PE) therapy, the potential therapeutic effects with novel medications in GBS, such as complement inhibitors, etc., have become the research focus in treatments. We found that epidemiological and clinical findings of GBS in China are approximately consistent with those in the International GBS Outcome Study (IGOS) cohort. We provided an overall picture of the present clinical status of GBS in China and summarized the global research progress of GBS, aiming to further understand the characteristics of GBS and improve the future work of GBS worldwide, especially in countries with the middle and low incomes.

Clinical and antibodies analysis of anti-GQ1b antibody syndrome: a case series of 15 patients

Objectives

To investigate the clinical manifestations, immunity, laboratory test, treatment and prognosis of patients with anti-GQ1b antibody syndrome in Chongqing, China.

Methods

We reviewed 15 patients with positive anti-ganglioside antibodies in the First Affiliated Hospital of Chongqing Medical University from 2016 to 2019.

Results

Fifteen patients were included in the study (mean age, 54.4 years; age range, 27 to 80 years; 9 men (60%)). Ten patients presented with a history of preinfection, including flu-like syndrome (n = 6, 60%), upper respiratory tract infection (URTI) (n = 3, 30%), and digestive tract infection (GI) (n = 1, 10%). The most common manifestation was ophthalmoplegia (n = 13, 86.67%), followed by weakness (n = 12, 80%), ataxia (n = 11, 73.3%), paresthesia (n = 8, 53.33%) and hypersomnolence (n = 5, 33.33%). All 15 patients underwent antibody testing. Eight patients (53.33%, 7 men (87.5%)) of whom only have positive immunoglobulin G (IgG) against anti-GQ1b antibody while seven (46.67%, 2 men (28.57%)) were positive for multiple anti-ganglioside antibodies apart from anti-GQ1b antibodies. Nine patients (60%) received intravenous immunoglobulin (IVIG) therapy, four (26.67%) received plasma exchange (PE) and two (13.33%) received steroid therapy. Three patients were lost to follow-up at 6 months, 1 patient (6.67%) had persistent back numbness, and the other 11 patients (73.33%) had fully recovered.

Conclusion

The clinical subtype of anti-GQ1b antibody syndrome correlates with the type of anti-ganglioside antibody. Patients who test positive for only anti-GQ1b antibody are more likely to be men. Most patients exhibit a unidirectional course with a good prognosis, but anti-GQ1b antibody syndrome is also associated with a risk of recurrence.

Risk Factors for Mechanical Ventilation in Patients with Guillain-Barré Syndrome

BACKGROUND

Respiratory support is required in 20-30% of patients with Guillain-Barré syndrome (GBS). We investigated clinical and biological risk factors for mechanical ventilation (MV) in northeast China through a retrospective GBS study. The Erasmus GBS Respiratory Insufficiency Score (EGRIS) is a prognostic model for MV in patients with GBS, and its usefulness has been validated in several countries but not in China. Therefore, we intended to validate the EGRIS model in our GBS cohort.

METHODS

A total of 252 patients with GBS were included in this study from January 2013 to October 2017. Risk factors for MV were identified via multivariate logistic regression analysis. The prognostic value of the EGRIS was validated via receiver operating characteristic curve analysis.

RESULTS

Thirty-one patients (12.3%) required MV (mean age 54.19 years), with a majority being male (77.4%). The risk factors for MV were male sex [odds ratio (OR) 3.720, 95% confidence interval (CI) 1.155-11.985, p < 0.05], shorter interval from onset to admission (OR 0.830, 95% CI 0.711-0.970, p < 0.05), lower Medical Research Council sum score at admission (OR 0.942, 95% CI 0.911-0.973, p < 0.001), neutrophil-to-lymphocyte ratio at admission (OR 1.174, 95% CI 1.049-1.315, p < 0.01), and cranial nerve deficit (OR 3.805, 95% CI 1.373-10.541, p < 0.05). The EGRIS had a good predictive ability for MV (area under the receiver operating curve 0.861) in patients with GBS, and a high EGRIS was a predictor for MV (OR 8.778, 95% CI 3.432-22.448, p < 0.001). However, there was no significant difference in ganglioside administration between ventilated and nonventilated patients.

CONCLUSIONS

An elevated neutrophil-to-lymphocyte ratio at admission and a high EGRIS could serve as predictors for MV in our GBS cohort.

Neuroinflammation, Microglia and Implications for Retinal Ganglion Cell Survival and Axon Regeneration in Traumatic Optic Neuropathy

Traumatic optic neuropathy (TON) refers to a pathological condition caused by a direct or indirect insult to the optic nerves, which often leads to a partial or permanent vision deficit due to the massive loss of retinal ganglion cells (RGCs) and their axonal fibers. Retinal microglia are immune-competent cells residing in the retina. In rodent models of optic nerve crush (ONC) injury, resident retinal microglia gradually become activated, form end-to-end alignments in the vicinity of degenerating RGC axons, and actively internalized them. Some activated microglia adopt an amoeboid morphology that engulf dying RGCs after ONC. In the injured optic nerve, the activated microglia contribute to the myelin debris clearance at the lesion site. However, phagocytic capacity of resident retinal microglia is extremely poor and therefore the clearance of cellular and myelin debris is largely ineffective. The presence of growth-inhibitory myelin debris and glial scar formed by reactive astrocytes inhibit the regeneration of RGC axons, which accounts for the poor visual function recovery in patients with TON. In this Review, we summarize the current understanding of resident retinal microglia in RGC survival and axon regeneration after ONC. Resident retinal microglia play a key role in facilitating Wallerian degeneration and the subsequent axon regeneration after ONC. However, they are also responsible for producing pro-inflammatory cytokines, chemokines, and reactive oxygen species that possess neurotoxic effects on RGCs. Intraocular inflammation triggers a massive influx of blood-borne myeloid cells which produce oncomodulin to promote RGC survival and axon regeneration. However, intraocular inflammation induces chronic neuroinflammation which exacerbates secondary tissue damages and limits visual function recovery after ONC. Activated retinal microglia is required for the proliferation of oligodendrocyte precursor cells (OPCs); however, sustained activation of retinal microglia suppress the differentiation of OPCs into mature oligodendrocytes for remyelination after injury. Collectively, controlled activation of retinal microglia and infiltrating myeloid cells facilitate axon regeneration and nerve repair. Recent advance in single-cell RNA-sequencing and identification of microglia-specific markers could improve our understanding on microglial biology and to facilitate the development of novel therapeutic strategies aiming to switch resident retinal microglia’s phenotype to foster neuroprotection.

Heat shock protein is a key therapeutic target for nerve repair in autoimmune peripheral neuropathy and severe peripheral nerve injury

Guillain-Barré syndrome (GBS) is an autoimmune peripheral neuropathy and a common cause of neuromuscular paralysis. Preceding infection induces the production of anti-ganglioside (GD) antibodies attacking its own peripheral nerves. In severe proximal peripheral nerve injuries that require long-distance axon regeneration, motor functional recovery is virtually nonexistent. Damaged axons fail to regrow and reinnervate target muscles. In mice, regenerating axons must reach the target muscle within 35 days (critical period) to reform functional neuromuscular junctions and regain motor function. Successful functional recovery depends on the rate of axon regeneration and debris removal (Wallerian degeneration) after nerve injury. The innate-immune response of the peripheral nervous system to nerve injury such as timing and magnitude of cytokine production is crucial for Wallerian degeneration. In the current study, forced expression of human heat shock protein (hHsp) 27 completely reversed anti-GD-induced inhibitory effects on nerve repair assessed by animal behavioral assays, electrophysiology and histology studies, and the beneficial effect was validated in a second mouse line of hHsp27. The protective effect of hHsp27 on prolonged muscle denervation was examined by performing repeated sciatic nerve crushes to delay regenerating axons from reaching distal muscle from 37 days up to 55 days. Strikingly, hHsp27 was able to extend the critical period of motor functional recovery for up to 55 days and preserve the integrity of axons and mitochondria in distal nerves. Cytokine array analysis demonstrated that a number of key cytokines which are heavily involved in the early phase of innate-immune response of Wallerian degeneration, were found to be upregulated in the sciatic nerve lysates of hHsp27 Tg mice at 1 day postinjury. However, persistent hyperinflammatory mediator changes were found after chronic denervation in sciatic nerves of littermate mice, but remained unchanged in hHsp27 Tg mice. Taken together, the current study provides insight into the development of therapeutic strategies to enhance muscle receptiveness (reinnervation) by accelerating axon regeneration and Wallerian degeneration.

Toxemia in Human Naturally Acquired Botulism

Human botulism is a severe disease characterized by flaccid paralysis and inhibition of certain gland secretions, notably salivary secretions, caused by inhibition of neurotransmitter release. Naturally acquired botulism occurs in three main forms: food-borne botulism by ingestion of preformed botulinum neurotoxin (BoNT) in food, botulism by intestinal colonization (infant botulism and intestinal toxemia botulism in infants above one year and adults), and wound botulism. A rapid laboratory confirmation of botulism is required for the appropriate management of patients. Detection of BoNT in the patient's sera is the most direct way to address the diagnosis of botulism. Based on previous published reports, botulinum toxemia was identified in about 70% of food-borne and wound botulism cases, and only in about 28% of infant botulism cases, in which the diagnosis is mainly confirmed from stool sample investigation. The presence of BoNT in serum depends on the BoNT amount ingested with contaminated food or produced locally in the intestine or wound, and the timeframe between serum sampling and disease onset. BoNT levels in patient's sera are most frequently low, requiring a highly sensitive method of detection. Mouse bioassay is still the most used method of botulism identification from serum samples. However, in vitro methods based on BoNT endopeptidase activity with detection by mass spectrometry or immunoassay have been developed and depending on BoNT type, are more sensitive than the mouse bioassay. These new assays show high specificity for individual BoNT types and allow more accurate differentiation between positive toxin sera from botulism and autoimmune neuropathy patients.

The Association of Anti-Ganglioside Antibodies in the Pathogenesis and Development of Zika-Associated Guillain-Barré Syndrome

Zika virus (ZIKV) has created major outbreaks all over the Americas and has caused severe neurological complications. The main neurological complications linked to ZIKV are Guillain-Barré syndrome (GBS), encephalitis, myelitis, and microcephaly. We thoroughly searched for published literature on PubMed and found evidence supporting the relationship between ZIKV and GBS. Through April 1, 2020, 429 publications were available on PubMed using the words “Zika associated GBS.” Among these, only four results linked anti-ganglioside antibodies to Zika-associated GBS. So, we expanded our search to other platforms like PubMed Central® (PMC), Google Scholar, and Cochrane, after which we shortlisted 28 studies. These studies include review articles, observational studies, case series, and case reports. The information collected from these articles were mainly based on the outbreaks in Latin America and the results that these patients showed in the course of the disease. It took a lag time of 7-10 days for the patients to develop Zika-associated GBS. We used all the evidence regarding the epidemiology, clinical manifestations, neurological complications, and diagnostic criteria that supported the findings of anti-ganglioside antibodies to ZIKV-associated GBS. Patients were detected with the presence of these antibodies in their urine through the enzyme-linked immunosorbent assay (ELISA) test. But the mechanism by which the ZIKV causes other complications like myelitis and encephalitis is still unknown and yet to be explored to develop treatment and management strategies.

Recurrent Guillain-Barré and Fisher Syndromes in Two Patients Who Were Subsequently Diagnosed with Aplastic Anemia

Guillain-Barré (GBS) and Fisher (FS) syndromes rarely recur and the characteristics of recurrence have not been fully elucidated. We describe the cases of 2 patients with GBS or FS that recurred more than twice and who were subsequently diagnosed with aplastic anemia. Case 1 was a 66-year-old man who was diagnosed with aplastic anemia 10 months before admission with limb ataxia and a sensory disturbance of the distal limbs that developed 3 days after an upper respiratory tract infection. He had a history of double vision with ataxia at the ages of 38 and 56 years. Case 2 was a 66-year-old woman who had been treated for aplastic anemia 1 year previously. She had a history of upper limb weakness after upper respiratory tract infections at the ages of 39 and 60 years. Tendon reflexes were absent in both patients at the time of onset and they were respectively diagnosed with FS and GBS and treated with intravenous immunoglobulin. No neurological deficits persisted. Blood findings showed that both were positive for IgG type ganglioside antibodies and HLA-DR15. The positive HLA-DR15 might have been associated with the recurrent GBS or FS and the development of aplastic anemia.

Clinical Characteristics of Intravenous Injection of Monosialotetrahexosyl Ganglioside Sodium-Related Guillain-Barre Syndrome

Introduction: Guillain Barre Syndrome (GBS) is an acute inflammatory immune-mediated multiple nerve root neuropathy. GBS primarily damages the spinal nerve root and peripheral nerves, but can also affect the cranial nerves and cause acute demyelination. This study analyzed the clinical features of intravenous injection of monosialotetrahexosyl ganglioside sodium-related Guillain-Barre syndrome (GRD-GBS). Methods: We retrospectively studied 12 patients who developed GRD-GBS after receiving monosialotetrahexosyl ganglioside sodium treatment in association with recent trauma, surgery, acute cerebrovascular disease, or chronic peripheral neuropathy. Clinical characteristics, electrophysiological examinations, serum-specific antibodies, and prognosis were assessed. As controls, we selected 12 patients hospitalized with non-ganglioside-related (NGRD)-GBS. Results: The positive rate of the ganglioside antibody test was significantly higher in the GRD-GBS group (66.67%) than in the NGRD-GBS group (8.33%). CSF protein levels were similar between the groups, but the incidence of blood-nerve-barrier (BNB) disruption was higher in the GRD-GBS group. Patient scores for the Hughes Functional Grading Scale (HFGS), a disability scale, were higher (more severe disability) in the GRD-GBS group than in the NGRD-GBS group. The HFGS scores of the GRD-GBS group did not change between peak onset and 30 days after discharge, but did change significantly by 90 days after discharge, while scores were significantly lower at both 30 and 90 days after discharge in the NGRD-GBS group. Conclusions: GRD-GBS patients showed more severe clinical manifestations, poorer prognosis, and slower recovery than patients with NGRD-GBS. Ganglioside treatment should be used with extreme caution in patients with trauma that damages the BNB.

Association of anti-gangliosides antibodies and anti-CMV antibodies in Guillain-Barré syndrome

INTRODUCTION

Numerous types of infection were closely related to GBS, mainly including Campylobacter jejuni, Cytomegalovirus, which may lead to the production of anti-gangliosides antibodies (AGA). Currently, although there are increased studies on the AGA and a few studies of anti-CMV antibodies in GBS, the association between them remains poorly documented. Therefore, our research aims to analyze the correlation of anti-CMV antibodies and AGA in GBS.

METHODS

A total of 29 patients with GBS were enrolled in this study. The CMV antibodies were tested by the electrochemiluminescence immunoassay "ECLIA" (Roche Diagnostics GmbH). The serum gangliosides were determined by The EUROLINE test kit.

RESULTS

Of the 29 patients with GBS, 9 (31%) were AGA-seropositive, in which 22 were CMV-IgG positive in CSF at the same time, but all 29 samples were CMV-IgM negative in both serum and CSF. In the AGA-positive group, the rate of both serum and CSF positive was 87.5% (7/8), higher than 50% (7/14) of the negative group, although no statistical significance was found. In addition, we found that there was a trend of higher ratio of men, a younger age onset, less frequent preceding infection, a higher level of CSF proteins, and less frequent cranial nerve deficits, although the data did not reach a statistical significance.

CONCLUSION

In spite of no statistical significance association was found between serum AGA and CMV-IgG in serum and CSF. However, we found that there was a trend of high positive rate of both serum and CSF-CMV-IgG in AGA-positive than the negative group. So we should further expand the sample size to analyze the association between AGA and CMV or other neurotropic virus antibodies in various diseases, to observe whether they could be serological marker of these diseases (especially GBS) or the underlying pathogenesis.