Fc receptor like 3 in Chinese patients of Han nationality with Guillain-Barré syndrome

Genetic basis of Guillain-Barre syndrome

Guillain-Barré syndrome (GBS) is an autoimmune disease in which the peripheral nerves are affected. GBS has different subtypes, such as acute inflammatory demyelinating polyneuropathy (AIDP) and acute motor axonal neuropathy (AMAN). Infections, e.g. Campylobacter jejuni, influenza, etc., can lead to GBS. Both environmental and genetic factors play a major role in the occurrence of GBS. Several studies have investigated the genetic basis of GBS. Human leukocyte antigens (HLA) genes, Cluster of Differentiation (CD) 1A, FAS, Fc gamma receptors (FcGR), Intercellular adhesion molecule-1 (ICAM1), different interleukins, Nucleotide oligomerization domain (NOD), Toll-like receptor 4 (TLR4), Tumor necrosis factor-α (TNF-α) are among the genes reported to be involved in susceptibility to the disease. Dysregulation and dysfunction of the mentioned gene products, even though their role in the pathogenesis of GBS is controversial, play a role in inflammatory pathways, regulation of immune cells and system, antigen presentation, axonal degeneration, apoptosis, and cross-reaction. This review aims to summarize associated genes with GBS to contribute to better understanding of GBS pathogenesis and discover the gene pathways that play role in GBS occurrence.

Genetic polymorphisms in Guillain-Barré Syndrome: A field synopsis and systematic meta-analysis

OBJECTIVE

Guillain-Barré Syndrome (GBS) is considered to be a complex immune-mediated neuropathy. In the past few years, numerous studies were performed to detect the association between genetic polymorphisms and GBS risk. However, the findings of these studies were controversial. Thus, we conducted this field synopsis and systematic meta-analysis for further evaluating the possible associations between all available genetic polymorphisms and GBS susceptibility.

METHODS

Relevant studies focusing on the association between all genetic polymorphisms and GBS risk were obtained by a comprehensive literature search. The pooled odds ratios (ORs) as well as 95% confidence intervals (CIs) were used for assessing the strength of association. Subgroup analyses stratified by ethnicity and GBS subtype were further performed. Moreover, sensitive analysis and publication bias were conducted for evaluating the reliability of the results.

RESULTS

Among the initial identified 333 articles, 41 articles reporting on 220 genetic polymorphisms were extracted for conducting this systematic review. Then, we performed 95 primary and 94 subgroup meta-analyses for 59 variants with at least three independent studies available. The results showed significant association between four variants (FcγR IIA rs1801274, TNF-α rs1800629, HLA DRB1*0401 and HLA DRB1*1301) and GBS susceptibility. In the subgroup analysis, three (TNF-α rs1800629, TNF-α rs1800630 and TLR4 rs4986790) and two (FcγR IIA rs1801274, HLA DRB1*14) variants showed association with increased GBS risk in Asian and Caucasian population, respectively. Also, TNF-α rs1800629 was significant associated with AMAN subtypes of GBS. Furthermore, sensitivity analysis, funnel plots and Egger's test displayed robust results, except for FcγR IIA rs1801274. Additionally, for 161 variants with less than three studies, 17 genetic variants have been found to be significantly related with GBS risk in our systematic review.

INTERPRETATION

In our study, we assessed the association between all available genetic polymorphisms and GBS susceptibility. We hope our findings would be helpful for identifying novel genetic biomarkers and potential therapeutic targets for GBS.

Associations between tumor necrosis factor-α gene polymorphisms and the risk of Guillain-Barré syndrome and its subtypes: A systematic review and meta-analysis

This meta-analysis aimed to assess the relationship between tumor necrosis factor-α (TNF-α) polymorphisms and Guillain-Barré syndrome (GBS) or its subtypes of acute inflammatory demyelinating polyneuropathy (AIDP), acute motor axonal neuropathy (AMAN), and acute motor-sensory axonal neuropathy (AMSAN). A total of six studies with 1013 cases and 1029 controls were included. Our pooled data indicated that TNF-α 308G/A polymorphism was significantly associated with GBS, AMAN, and AMSAN but not with AIDP; TNF-α 857C/T polymorphism was significantly associated with AMAN but not with GBS or AIDP. Besides, no association was found between TNF-α 238G/A and 863C/A polymorphisms and GBS or its subtypes.

Zika Virus as an Emerging Neuropathogen: Mechanisms of Neurovirulence and Neuro-Immune Interactions

Zika virus (ZIKV) is an emerging arbovirus of the genus Flaviviridae, which causes a febrile illness and has spread from across the Pacific to the Americas in a short timeframe. Convincing evidence has implicated the ZIKV to incident cases of neonatal microcephaly and a set of neurodevelopmental abnormalities referred to as the congenital Zika virus syndrome. In addition, emerging data points to an association with the ZIKV and the development of the so-called Guillain-Barre syndrome, an acute autoimmune polyneuropathy. Accumulating knowledge suggests that neurovirulent strains of the ZIKV have evolved from less pathogenic lineages of the virus. Nevertheless, mechanisms of neurovirulence and host-pathogen neuro-immune interactions remain incompletely elucidated. This review provides a critical discussion of genetic and structural alterations in the ZIKV which could have contributed to the emergence of neurovirulent strains. In addition, a mechanistic framework of neuro-immune mechanisms related to the emergence of neuropathology after ZIKV infection is discussed. Recent advances in knowledge point to avenues for the development of a putative vaccine as well as novel therapeutic strategies. Nevertheless, there are unique unmet challenges that need to be addressed in this regard. Finally, a research agenda is proposed.

A Case of Acute Motor Axonal Neuropathy Mimicking Brain Death and Review of the Literature

We describe a case report of fulminant Guillain-Barré syndrome (GBS) mimicking brain death. A previously healthy 60-year-old male was admitted to the neurointensive care unit after developing rapidly progressive weakness and respiratory failure. On presentation, the patient was found to have absent brainstem and spinal cord reflexes resembling that of brain death. Acute motor axonal neuropathy, a subtype of GBS, was diagnosed by cerebrospinal fluid and nerve conduction velocity testing. An electroencephalogram showed that the patient had normal, appropriately reactive brain function. Transcranial Doppler (TCD) ultrasound showed appropriate blood flow to the brain. GBS rarely presents with weakness so severe as to mimic brain death. This article provides a review of similar literature. This case demonstrates the importance of performing a proper brain death examination, which includes evaluation for irreversible cerebral injury, exclusion of any confounding conditions, and performance of tests such as electroencephalography and TCDs when uncertainty exists about the reliability of the clinical exam.

Biomarkers of Guillain-Barré Syndrome: Some Recent Progress, More Still to Be Explored

Guillain-Barré syndrome (GBS), the axonal subtype of which is mainly triggered by C. jejuni with ganglioside-mimicking lipooligosaccharides (LOS), is an immune-mediated disorder in the peripheral nervous system (PNS) accompanied by the disruption of the blood-nerve barrier (BNB) and the blood-cerebrospinal fluid barrier (B-CSF-B). Biomarkers of GBS have been extensively explored and some of them are proved to assist in the clinical diagnosis and in monitoring disease progression as well as in assessing the efficacy of immunotherapy. Herein, we systemically review the literature on biomarkers of GBS, including infection-/immune-/BNB, B-CSF-B, and PNS damage-associated biomarkers, aiming at providing an overview of GBS biomarkers and guiding further investigations. Furthermore, we point out further directions for studies on GBS biomarkers.

Adversomics: a new paradigm for vaccine safety and design

Despite the enormous population benefits of routine vaccination, vaccine adverse events (AEs) and reactions, whether real or perceived, have posed one of the greatest barriers to vaccine acceptance--and thus to infectious disease prevention--worldwide. A truly integrated clinical, translational, and basic science approach is required to understand the mechanisms behind vaccine AEs, predict them, and then apply this knowledge to new vaccine design approaches that decrease, or avoid, these events. The term 'adversomics' was first introduced in 2009 and refers to the study of vaccine adverse reactions using immunogenomics and systems biology approaches. In this review, we present the current state of adversomics research, review known associations and mechanisms of vaccine AEs/reactions, and outline a plan for the further development of this emerging research field.