Th1/Th2/Th17/Treg cytokines in Guillain–Barré syndrome and experimental autoimmune neuritis

Animal models of immune-mediated demyelinating polyneuropathies

Immune-mediated demyelinating polyneuropathies (IMDPs) are rare disorders in which dysregulated adaptive immune responses cause peripheral nerve demyelinating inflammation and axonal injury in susceptible individuals. Despite significant advances in understanding IMDP pathogenesis guided by patient data and representative mammalian models, specific therapies are lacking. Significant knowledge gaps in IMDP pathogenesis still exist, e.g. precise antigen(s) and mechanisms that initially trigger immune system activation and identification of large population disease susceptibility factors. The initial directional cues for antigen-specific effector or autoreactive leukocyte trafficking into peripheral nerves are also unknown. An overview of current animal models, with emphasis on the experimental autoimmune neuritis and spontaneous autoimmune peripheral polyneuropathy models, is provided. Insights on the initial directional cues for peripheral nerve tissue specific autoimmunity using a novel Major Histocompatibility Complex class II conditional knockout mouse strain are also discussed, suggesting an essential research tool to study cell- and time-dependent adaptive immunity in autoimmune diseases.

Case report and brief literature review: possible association of secukinumab with Guillain-Barré syndrome in psoriasis

The etiology of Guillain-Barré syndrome (GBS) may be autoimmune. About two-thirds of patients typically experience their first symptoms within 5 days to 3 weeks after common infectious diseases, surgery, or vaccination. Infection is a triggering factor for over 50% of patients. In recent years, a growing number of studies have indicated that some immune checkpoint inhibitors and COVID-19 may also contribute to the occurrence of GBS. However, drugs are considered a rare cause of GBS. The patient in our case was a 70-year-old man who developed GBS after initiating secukinumab for psoriasis. Upon diagnosis suggesting a potential association between secukinumab and the development of GBS, as per the Naranjo adverse drug reaction (ADR) probability scale, we decided to discontinue the drug. Following this intervention, along with the administration of immunoglobulin, the patient exhibited a significant improvement in extremity weakness. The association of GBS with secukinumab treatment, as observed in this case, appears to be uncommon. The underlying mechanisms that may link secukinumab to the development of GBS are not yet fully understood and warrant further scientific inquiry and rigorous investigation. However, we hope that this report can raise greater awareness and vigilance among medical professionals to enhance the safety of patients' medication.

Guillain-Barre syndrome and link with COVID-19 infection and vaccination: a review of literature

Background

Guillain-Barré syndrome (GBS) is an autoimmune disease associated with significant morbidity. A wide variety of infectious and non-infectious triggers have been identified to be associated with GBS. COVID-19 has gained attention in recent years for its role in GBS pathogenesis. Our study aims to review the literature on GBS and its epidemiological and pathophysiological association with COVID-19.

Description

Recent literature on GBS associated with COVID-19 infections, such as case reports, case series, systematic reviews, and large-scale epidemiological studies, were reviewed. We also reviewed studies that included vaccines against COVID-19 in association with GBS. Studies that focused on understanding the pathobiology of GBS and its association with infectious agents including COVID-19 were reviewed.

Conclusion

Despite a lack of consensus, GBS is strongly associated with COVID-19 infection. The exact pathophysiological mechanism regarding COVID-19 as a causative agent of GBS is unknown. Mechanisms, such as the proinflammatory state, triggering of autoimmunity, and direct viral invasion, are postulated and remain to be investigated. Adenovirus vector vaccines are most likely associated with GBS, and the consensual reports clearly suggest mRNA vaccines are associated with low risk and may be protective against GBS by reducing the risk of COVID-19 infection.

P2X7 receptor antagonists modulate experimental autoimmune neuritis via regulation of NLRP3 inflammasome activation and Th17 and Th1 cell differentiation

BACKGROUND

Guillain-Barré syndrome (GBS), a post-infectious, immune-mediated, acute demyelinating disease of the peripheral nerves and nerve roots, represents the most prevalent and severe acute paralyzing neuropathy. Purinergic P2X7 receptors (P2X7R) play a crucial role in central nervous system inflammation. However, little is known about their role in the immune-inflammatory response within the peripheral nervous system.

METHODS

Initially, we assessed the expression of purinergic P2X7R in the peripheral blood of patients with GBS using flow cytometry and qRT-PCR. Next, we explored the expression of P2 X7R in CD4+ T cells, CD8+ T cells, and macrophages within the sciatic nerves and spleens of rats using immunofluorescence labeling and flow cytometry. The P2X7R antagonist brilliant blue G (BBG) was employed to examine its therapeutic impact on rats with experimental autoimmune neuritis (EAN) induced by immunization with the P0180 - 199 peptide. We analyzed CD4+ T cell differentiation in splenic mononuclear cells using flow cytometry, assessed Th17 cell differentiation in the sciatic nerve through immunofluorescence staining, and examined the expression of pro-inflammatory cytokine mRNA using RT-PCR. Additionally, we performed protein blotting to assess the expression of P2X7R and NLRP3-related inflammatory proteins within the sciatic nerve. Lastly, we utilized flow cytometry and immunofluorescence labeling to examine the expression of NLRP3 on CD4+ T cells in rats with EAN.

RESULTS

P2X7R expression was elevated not only in the peripheral blood of patients with GBS but also in rats with EAN. In rats with EAN, inhibiting P2X7R with BBG alleviated neurological symptoms, reduced demyelination, decreased inflammatory cell infiltration of the peripheral nerves, and improved nerve conduction. BBG also limited the production of pro-inflammatory molecules, down-regulated the expression of P2X7R and NLRP3, and suppressed the differentiation of Th1 and Th17 cells, thus protecting against EAN. These effects collectively contribute to modifying the inflammatory environment and enhancing outcomes in EAN rats.

CONCLUSIONS

Suppression of P2X7R relieved EAN manifestation by regulating CD4+ T cell differentiation and NLRP3 inflammasome activation. This finding underscores the potential significance of P2X7R as a target for anti-inflammatory treatments, advancing research and management of GBS.

Integrated gene expression profiling and functional enrichment analyses to discover biomarkers and pathways associated with Guillain-Barré syndrome and autism spectrum disorder to identify new therapeutic targets

Guillain-Barré syndrome (GBS) is one of the most prominent and acute immune-mediated peripheral neuropathy, while autism spectrum disorders (ASD) are a group of heterogeneous neurodevelopmental disorders. The complete mechanism regarding the neuropathophysiology of these disorders is still ambiguous. Even after recent breakthroughs in molecular biology, the link between GBS and ASD remains a mystery. Therefore, we have implemented well-established bioinformatic techniques to identify potential biomarkers and drug candidates for GBS and ASD. 17 common differentially expressed genes (DEGs) were identified for these two disorders, which later guided the rest of the research. Common genes identified the protein-protein interaction (PPI) network and pathways associated with both disorders. Based on the PPI network, the constructed hub gene and module analysis network determined two common DEGs, namely CXCL9 and CXCL10, which are vital in predicting the top drug candidates. Furthermore, coregulatory networks of TF-gene and TF-miRNA were built to detect the regulatory biomolecules. Among drug candidates, imatinib had the highest docking and MM-GBSA score with the well-known chemokine receptor CXCR3 and remained stable during the 100 ns molecular dynamics simulation validated by the principal component analysis and the dynamic cross-correlation map. This study predicted the gene-based disease network for GBS and ASD and suggested prospective drug candidates. However, more in-depth research is required for clinical validation.Communicated by Ramaswamy H. Sarma.

Lactobacillus paracasei L9 affects disease progression in experimental autoimmune neuritis by regulating intestinal flora structure and arginine metabolism

BACKGROUND

Autoimmune neuropathies are common peripheral nervous system (PNS) disorders. Environmental influences and dietary components are known to affect the course of autoimmune diseases. Intestinal microorganisms can be dynamically regulated through diet, and this study combines intestinal microorganisms with diseases to open up new therapeutic ideas.

METHODS

In Lewis rats, a model of EAN was established with P0 peptide, Lactobacillus were used as treatment, serum T-cell ratio, inflammatory factors, sciatic neuropathological changes, and pathological inflammatory effects on intestinal mucosa were detected, and fecal metabolomics and 16 s microbiome analysis were performed to further explore the mechanism.

RESULTS

In the EAN rat model, Lactobacillus paracasei L9 (LP) could dynamically regulate the CD4⁺/CD8⁺T balance in serum, reduce serum IL-1, IL-6 and TNF-α expression levels, improve sciatic nerve demyelination and inflammatory infiltration, and reduce nervous system score. In the rat model of EAN, intestinal mucosa was damaged. Occludin and ZO-1 were downregulated. IL-1, TNF-α and Reg3γ were upregulated. LP gavage induced intestinal mucosa recovery; occludin and ZO-1 upregulation; IL-1, TNF-α and Reg3γ downregulation. Finally, metabolomics and 16 s microbiome analysis were performed, and differential metabolites were enriched with an important metabolic pathway, arginine and proline metabolism.

CONCLUSION

LP improved EAN in rats by influencing intestinal community and the lysine and proline metabolism.

COVID-19 as a trigger of Guillain-Barré syndrome: A review of the molecular mechanism

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused a pandemic with serious complications. After coronavirus disease 2019 (COVID-19), several post-acute COVID-19 syndromes (PACSs) and long-COVID sequels were reported. PACSs involve many organs, including the nervous, gustatory, and immune systems. One of the PACSs after SARS-CoV-2 infection and vaccination is Guillain-Barré syndrome (GBS). The incidence rate of GBS after SARS-CoV-2 infection or vaccination is low. However, the high prevalence of COVID-19 and severe complications of GBS, for example, autonomic dysfunction and respiratory failure, highlight the importance of post-COVID-19 GBS. It is while patients with simultaneous COVID-19 and GBS seem to have higher admission rates to the intensive care unit, and demyelination is more aggressive in post-COVID-19 GBS patients. SARS-CoV-2 can trigger GBS via several pathways like direct neurotropism and neurovirulence, microvascular dysfunction and oxidative stress, immune system disruption, molecular mimicry, and autoantibody production. Although there are few molecular studies on the molecular and cellular mechanisms of GBS occurrence after SARS-CoV-2 infection and vaccination, we aimed to discuss the possible pathomechanism of post-COVID-19 GBS by gathering the most recent molecular evidence.

Neutrophil-to-lymphocyte ratio is a risk indicator of Guillain-Barré syndrome and is associated with severity and short-term prognosis

Introduction

Guillain-Barré syndrome (GBS) is an autoimmune disorder targeting the peripheral nervous system. The neutrophil-to-lymphocyte ratio (NLR), a simple indicator of immune function, is potentially related to its incidence and severity; however, this should be confirmed. We aimed to evaluate the role of NLR in the diagnosis, severity, and prognosis of GBS.

Methods

Data of GBS patients and controls visiting our hospital from January 2010 to December 2020 were retrospectively analyzed (Clinical trial registration: ChiCTR2100053540). Risk factors were determined through logistic regression. Smoothing curves, receiver-operating characteristic curves, and forest plots were drawn.

Results

We included 136 GBS patients and 211 controls. NLR, as a continuous variable, was associated with GBS risk (OR, 2.32; 95% CI, 1.68-3.21; p < 0.001), severe functional disability (OR, 1.23; 95% CI, 1.06-1.43; p = 0.006), severe weakness (OR, 1.19; 95% CI, 1.06-1.35, p = 0.004), and short-term prognosis (OR, 1.21; 95% CI, 1.08-1.36; p = 0.001). NLR was more strongly associated with GBS risk in older (≥60 years) (OR, 7.17; 95% CI, 2.38-21.61) or male (OR, 2.88; 95% CI, 1.78-4.64) patients than in younger (<60 years) (OR, 1.88; 95% CI, 1.37-2.57) or female (OR, 1.85; 95% CI, 1.24-2.77) patients. NLR was significantly associated with severe functional disability in faster disease progression (OR, 1.53; 95% CI, 1.03-12.29) and male patients (OR, 1.41; 95% CI, 1.03-1.92) versus in slower disease progression (OR, 1.12; 95% CI, 0.77-1.64) and female patients (OR, 1.12; 95% CI, 0.77-1.64).

Conclusions

NLR may be an independent GBS risk factor and predictor of severe functional disability, severe weakness, and short-term prognosis.

Is there a causal nexus between COVID-19 infection, COVID-19 vaccination, and Guillain-Barré syndrome?

Guillain-Barré syndrome (GBS) is an immune-mediated inflammatory polyradiculoneuropathy, which commonly leads to a very high level of neurological disability. Especially, after the global outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, the causation between GBS and SARS-CoV-2 infection and the coronavirus disease 2019 (COVID-19) vaccination have aroused widespread concern. In the review, we analyzed the impacts of SARS-CoV-2 infection and COVID-19 vaccination on GBS globally, aiming to further understand the characteristics of GBS associated with COVID-19. Based on the electrophysiological data, patients suffering from GBS related to COVID-19 manifested as an acute inflammatory demyelinating polyneuropathy (AIDP). Moreover, we summarized the current findings, which may evidence GBS linking to SARS-CoV-2 infection and COVID-19 vaccination, and discussed the underlying mechanisms whether and how the SARS-CoV-2 virus and COVID-19 vaccination can induce GBS and its variants.

Siponimod ameliorates experimental autoimmune neuritis

BACKGROUND

Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating polyneuropathy (CIDP) are human autoimmune peripheral neuropathy. Besides humoral immunity, cellular immunity is also believed to contribute to these pathologies, especially CIDP. Sphingosine-1-phosphate receptor 1 (S1PR1) regulates the maturation, migration, and trafficking of lymphocytes. As of date, the therapeutic effect of sphingosine-1-phosphate receptor (S1PR) agonists on patients with GBS or CIDP remains unclear.

METHODS

To evaluate the effect of siponimod, an agonist of S1PR1 and S1PR5, on experimental autoimmune neuritis (EAN), an animal model of autoimmune peripheral neuropathy, was used. Lewis rats were immunized with 125 μg of synthetic peptide from bovine P2 protein. Rats in the siponimod group were orally administered 1.0 mg/kg siponimod and those in the EAN group were administrated the vehicle on days 5-27 post-immunization (p.i.) daily. The symptom severity was recorded daily. The changes in the expression of cytokines and transcription factors in the lymph nodes and cauda equina (CE) which correlate with the pathogenesis of EAN and recovery of injured nerve were measured using reverse transcription quantitative PCR. Histological study of CE was also performed.

RESULTS

Flaccid paralysis developed on day 11 p.i. in both groups. Siponimod relieved the symptom severity and decreased the expression of interferon-gamma and IL-10 mRNAs in lymph nodes and CE compared with that in the EAN group. The expression of Jun proto-oncogene (c-Jun) mRNA increased from the peak to the recovery phase and that of Sonic hedgehog signaling molecule (Shh) and Glial cell line-derived neurotrophic factor (Gdnf) increased prior to increase in c-Jun with no difference observed between the two groups. Histologically, siponimod also reduced demyelinating lesions and inflammatory cell invasion in CE.

CONCLUSIONS

Siponimod has a potential to ameliorate EAN. Shh and Gdnf, as well as C-Jun played a significant role during the recovery of injured nerves.

Relationship between Hypoxic and Immune Pathways Activation in the Progression of Neuroinflammation: Role of HIF-1α and Th17 Cells

Neuroinflammation is a common event in degenerative diseases of the central and peripheral nervous system, triggered by alterations in the immune system or inflammatory cascade. The pathophysiology of these disorders is multifactorial, whereby the therapy available has low clinical efficacy. This review propounds the relationship between the deregulation of T helper cells and hypoxia, mainly Th17 and HIF-1α molecular pathways, events that are involved in the occurrence of the neuroinflammation. The clinical expression of neuroinflammation is included in prevalent pathologies such as multiple sclerosis, Guillain-Barré syndrome, and Alzheimer's disease, among others. In addition, therapeutic targets are analyzed in relation to the pathways that induced neuroinflammation.

Case Report: Chlamydia psittaci pneumonia complicated by Guillain-Barré syndrome detected using metagenomic next-generation sequencing

Psittacosis and Guillain-Barré syndrome are both rare clinical diseases with low incidence, and their combination has rarely been reported. Here, we report a case of Chlamydia psittaci pneumonia combined with Guillain-Barré syndrome. The patient initially presented with high fever, difficulty breathing, and fatigue. Chest computerised tomography indicated large consolidation opacities in both lungs. Metagenomic next-generation sequencing clearly identified the pathogen as C. psittaci. The patient's fever subsided after targeted antibiotic treatment, but difficulty breathing and fatigue worsened, and the patient developed symmetric limb numbness and weakness. Lumbar puncture, electrophysiological examination, and clinical characteristics were suggestive of Guillain-Barré syndrome, and the symptoms improved after treatment with human immunoglobulin. The results of this study suggest that metagenomic next-generation sequencing is useful for the rapid diagnosis of pulmonary infectious agents. Psittacosis is closely associated with the development of Guillain-Barré syndrome; however, more cases are needed to support this conclusion, and early targeted antibiotic treatment, immunotherapy, and basic supportive treatment are essential for improving outcomes.

Observation on the efficacy of sublingual immunotherapy with dust mite allergen for perennial allergic rhinitis and the mechanism of action on ILCs with ILC1s and ILC2s and ILC3s

BACKGROUND

Allergic rhinitis (AR) is considered to be 1 of the most difficult diseases to treat globally. It has a serious impact on the quality of life and social economy of patients and has become an important global health problem. Several drugs have been recommended to treat AR, but their effectiveness and mechanism of action in these patients remain unclear. The purpose of this study will be to compare the efficacy and mechanism of action of 2 drugs for the treatment of AR (moderate to severe): a Dermatophagoides Farinae Drops Sublingual Immunotherapy and a Momethasone Furoate nasal spray as an adjunct to the treatment of subjects with AR.

METHODS

A randomized, prospective, double-blind (patient and evaluator) clinical trial. The participants (n = 60) will be randomly distributed into 2 groups. The experimental group will receive a sublingual Immunotherapy for 3 months. The control group will receive the mometasone furoate nasal spray for 3 months. Before treatment, 1 month and 3 months after treatment, total nasal symptom score scale, Visual analogue Scale and Quality of Life questionnaire of rhinoconjunctivitis will be measured and Changes of the serums of IgE, interferon-γ, IL-4, IL-17, tumor necrosis factor-α, IL-5, IL-9, IL-13, IL-25, IL-33, vascular endothelial growth factor, TSLP and IL-22 in both groups. The measurements will be performed by the same researcher who was unaware of the participants' subgroup.

DISCUSSION

We believe that the treatment of perennial AR with sublingual Immunotherapy and nasal hormones will be more effective in these patients. Furthermore, the sublingual Immunotherapy mainly acts mostly on the cellular immunity, while nasal hormones mainly act on local inflammatory responses. We expect to clarify which treatments are more effective and how they work in improving perennial AR.

Immune Modifying Effect of Drug Free Biodegradable Nanoparticles on Disease Course of Experimental Autoimmune Neuritis

Guillain-Barre syndrome (GBS) is an autoimmune disease of demyelination and inflammation of peripheral nerves. Current treatments are limited to plasma exchange and intravenous immunoglobulins. Cargo-free nanoparticles (NPs) have been evaluated here for their therapeutic benefit on the disease course of experimental autoimmune neuritis (EAN), mimicking the human GBS. NPs prepared from poly-lactic co-glycolic acid (PLGA) with variable size and surface charge (i.e., 500 nm vs. 130 nm, polyvinyl alcohol (PVA) vs. sodium cholate), were intravenously administered in before- or early-onset treatment schedules in a rat EAN model. NP treatment mitigated distinctly the clinical severity of EAN as compared to the P2-peptide control group (P2) in all treatments and reduced the trafficking of inflammatory monocytes at inflammatory loci and diverted them towards the spleen. Therapeutic treatment with NPs reduced the expression of proinflammatory markers (CD68 (P2: 34.8 ± 6.6 vs. NP: 11.9 ± 2.3), IL-1β (P2: 18.3 ± 0.8 vs. NP: 5.8 ± 2.2), TNF-α (P2: 23.5 ± 3.7 vs. NP: 8.3 ± 1.7) and elevated the expression levels of anti-inflammatory markers CD163 (P2: 19.7 ± 3.0 vs. NP: 41.1 ± 6.5; all for NP-PVA of 130 nm; relative to healthy control). These results highlight the therapeutic potential of such cargo-free NPs in treating EAN, which would be easily translatable into clinical use due to their well-known low-toxicity profile.

Role of lymphocyte-related immune-inflammatory biomarkers in detecting early progression of Guillain-Barré syndrome

OBJECTIVES

This study aimed to investigate the role of peripheral neutrophil to lymphocyte ratio (NLR), monocyte to lymphocyte ratio (MLR), and platelet to lymphocyte ratio (PLR) in the progression and severity of the Guillain-Barré syndrome (GBS).

METHODS

47 GBS patients and 50 age and sex-matched healthy controls (HC) were retrospectively included. Demographic and clinical assessment data were reviewed and abstracted. NLR, MLR, and PLR were calculated based on the peripheral blood tests by reviewing clinical data. The relationship between the Hughes' score and NLR, MLR, PLR levels was investigated.

RESULTS

The GBS patients had higher NLR levels (P < 0.001), MLR levels (P = 0.001) and PLR levels (P < 0.001) than those in HC. And patients with severe disability score (Hughes' score ≥ 3) had significantly higher NLR (P = 0.007), MLR (P = 0.04), PLR (P = 0.013). Spearman correlation analysis indicated that NLR was positively associated with the Hughes' score (r = 0.331, P = 0.023). In the patients with acute inflammatory demyelinating polyneuropathy (AIDP), Spearman correlation analysis indicated that NLR, MLR and PLR were positively associated to the Hughes' score (r = 0.825, P = 0.001 for NLR, r = 0.727, P = 0.005 for MLR, and r = 0.723, P = 0.005 for PLR).

CONCLUSIONS

NLR, MLR, and PLR may be indicators of disease activity in patients with GBS or AIDP. These parameters may benefit the active treatment of GBS patients with a high degree of disability.

Intestinal Immune Development Is Accompanied by Temporal Deviation in Microbiota Composition of Newly Hatched Pigeon Squabs

Identifying the interaction between intestinal mucosal immune system development and commensal microbiota colonization in neonates is of paramount importance for understanding how early life events affect resistance to disease later in life. However, knowledge about this interaction during the early posthatch development period in altrices is limited. To fill this gap, samples of intestinal content and tissue were collected from newly hatched pigeon squabs at four time points (days 0, 7, 14, and 21) for microbial community analysis and genome-wide transcriptome profiling, respectively. We show that the first week after hatching seems to be the critical window for ileal microbiota colonization and that a potentially stable microbiota has not yet been well established at 21 days of age. Regional transcriptome differences revealed that the jejunum rather than the ileum plays a crucial role in immunity at both the innate and adaptive levels. In the ileum, temporal deviation in innate immune-related genes mainly occurs in the first week of life and is accompanied by a temporal change in microbiota composition, indicating that the ileal innate mucosal immune system development regulated by microbial colonization occurs mainly in this period. Furthermore, we provide evidence that colonization by Escherichia and Lactobacillus within the first week of life is likely one of the causative factors for the induction of proinflammatory cytokine expression in the ileum. We also demonstrate that cellular adaptive immune responses mediated by Th17 cells following commensal-induced proinflammatory cytokine production in the ileum begin as early as the first week posthatch, but this cellular immunity seems to be less effective in terms of maintaining the inflammatory response balance. Because the induction of high levels of mucosal secretory IgA (SIgA) seems to take approximately 3 weeks, we favor the idea that humoral adaptive immunity might be less active, at least, during the first 2 weeks of life. Our data may help to explain the phenomenon of the occurrence of intestinal infections mainly in the ileum of pigeon squabs during the early posthatch period. IMPORTANCE The pigeon (Columba livia), an altricial bird, is one of the most economically important farmed poultry for table purposes. Identifying the interaction between intestinal mucosal immune system development and commensal microbiota colonization in neonates is of paramount importance for understanding how early life events affect resistance to disease and potential productivity later in life. However, knowledge about this interaction during the early posthatch development period in altricial birds is limited. The study described herein is the first to try to provide insights into this interaction. Our data provide evidence on the mutual relationship between intestinal mucosal immune system development and commensal microbiota colonization in pigeon squabs and may help to explain the phenomenon of the occurrence of intestinal infections mainly in the ileum of pigeon squabs during the early posthatch period.

Guillain-Barré syndrome with transition from hashimoto's to graves' disease: a case report

BACKGROUND

On rare occasions, there can be a transition from Hashimoto's to Graves' disease. However, there are no reported cases of transition from Hashimoto's to Graves' disease triggered by the onset of Guillain-Barré syndrome.

CASE PRESENTATION

Sixteen years prior, a 55-year-old woman was diagnosed with Hashimoto's disease and followed up without medication. One week after the appearance of signs of intestinal inflammation, weakness in the extremities was observed, and a cerebrospinal fluid test was positive for anti-GM1 IgG antibody, leading to the diagnosis of Guillain-Barré syndrome. In addition, hyperthyroidism was observed at the time of admission, and Graves' disease was diagnosed based on autoantibodies and thyroid echoes. Numbness in the extremities was relieved by high-dose intravenous gamma globulin.

CONCLUSION

With the onset of Guillain-Barré syndrome, helper T cells became predominantly type 1, effector B cells increased in number, and thyroid-stimulating antibodies were produced, leading to the conclusion that Hashimoto's disease progressed to Graves' disease. Therefore, it is necessary to pay attention to the transition of thyroid function during Guillain-Barré syndrome.

Computer simulation of the Receptor-Ligand Interactions of Mannose Receptor CD206 in Comparison with the Lectin Concanavalin A Model

Computer modeling of complexation of mono- and oligosaccharide ligands with the main (fourth) carbohydrate-binding domain of the mannose receptor CD206 (CRD4), as well as with the model receptor concanavalin A (ConA), was carried out for the first time, using methods of molecular dynamics and neural network analysis. ConA was shown to be a relevant model of CD206 (CRD4) due to similarity of the structural organization of the binding sites and high correlation of the values of free energies of complexation between the literature data and computer modeling (r > 0.9). Role of the main factors affecting affinity of the ligand–receptor interactions is discussed: the number and nature of carbohydrate residues, presence of Me-group in the O1 position, type of the glycoside bond in dimannose. Complexation of ConA and CD206 with ligands is shown to be energetically caused by electrostatic interactions (E) of the charged residues (Asn, Asp, Arg) with oxygen and hydrogen atoms in carbohydrates; contributions of hydrophobic and van der Waals components is lower. Possibility of the additional stabilization of complexes due to the CH–π stacking interactions of Tyr with the Man plane is discussed. The role of calcium and manganese ions in binding ligands has been studied. The values of free energies of complexation calculated in the course of molecular dynamics simulation correlate with experimental data (published for the model ConA): correlation coefficient r = 0.68. The Pafnucy neural network was trained based on the set of PDBbind2020 ligand–receptor complexes, which significantly increased accuracy of the energy predictions to r = 0.8 and 0.82 for CD206 and ConA receptors, respectively. A model of normalization of the complexation energy values for calculating the relevant values of ΔG_bind, K_d is proposed. Based on the developed technique, values of the dissociation constants of a series of CD206 complexes with nine carbohydrate ligands of different structures were determined, which were not previously known. The obtained data open up possibilities for using computer modeling for the development of optimal drug carriers capable of active macrophage targeting, and also determine the limits of applicability of using ConA as a relevant model for studying parameters of the CD206 binding to various carbohydrate ligands.

Role of Toll-Like Receptors in Neuroimmune Diseases: Therapeutic Targets and Problems

Toll-like receptors (TLRs) are a class of proteins playing a key role in innate and adaptive immune responses. TLRs are involved in the development and progression of neuroimmune diseases via initiating inflammatory responses. Thus, targeting TLRs signaling pathway may be considered as a potential therapy for neuroimmune diseases. However, the role of TLRs is elusive and complex in neuroimmune diseases. In addition to the inadequate immune response of TLRs inhibitors in the experiments, the recent studies also demonstrated that partial activation of TLRs is conducive to the production of anti-inflammatory factors and nervous system repair. Exploring the mechanism of TLRs in neuroimmune diseases and combining with developing the emerging drug may conquer neuroimmune diseases in the future. Herein, we provide an overview of the role of TLRs in several neuroimmune diseases, including multiple sclerosis, neuromyelitis optica spectrum disorder, Guillain-Barré syndrome and myasthenia gravis. Emerging difficulties and potential solutions in clinical application of TLRs inhibitors will also be discussed.

Case Report: Plasma Biomarkers Reflect Immune Mechanisms of Guillain-Barré Syndrome

This case series reported a group of patients with Guillain-Barré syndrome (GBS) and their plasma cytokine changes before and after immunotherapy. We aimed to understand GBS's pathogenesis and pathophysiology through observing the interval differences of the representative cytokines, which were the thymus and activation regulated chemokine (TARC) for T-cell chemotaxis, CD40 ligand (CD40L) for cosimulation of B and T cells, activated complement component C5/C5a, and brain-derived neurotrophic factor (BDNF) for survival and regenerative responses to nerve injuries. The fluorescence magnetic bead-based multiplexing immunoassay simultaneously quantified the five cytokines in a single sample. From June 2018 to December 2019, we enrolled five GBS patients who had completed before-after blood cytokine measurements. One patient was diagnosed with paraneoplastic GBS and excluded from the following cytokine analysis. The BDNF level decreased consistently in all the patients and made it a potential biomarker for the acute stage of GBS. Interval changes of the other four cytokines were relatively inconsistent and possibly related to interindividual differences in the immune response to GBS triggers, types of GBS variants, and classes of antiganglioside antibodies. In summary, utilizing the multiplexing immunoassay helps in understanding the complex immune mechanisms of GBS and the variation of immune responses in GBS subtypes; this method is feasible for identifying potential biomarkers of GBS.

Surfactant protein A modulates the activities of the JAK/STAT pathway in suppressing Th1 and Th17 polarization in murine OVA-induced allergic asthma

Asthma is an allergic inflammatory lung disease affecting nearly 300 million people worldwide. To better understand asthma, new regulators must be identified. We conducted a study to investigate the effect and mechanisms of action of surfactant protein A (SPA) in OVA-induced asthmatic mice. Treatment with SPA delayed the onset of asthma, decreased its severity, as well as notably suppressed pro-inflammatory cytokine production. Furthermore, SPA-treated mice possessed more leukocytes; more CD4+ T cells infiltrated the spleen in the SPA-treated mice than in the control mice, and there were decreased percentages of Th1 and Th17 cells in vivo. In addition, expression levels of the T-bet (Th1 transcription factor) and RORγt (Th17 transcription factor) genes were significantly downregulated by SPA treatment. Moreover, SPA reduced the production and mRNA expression of pro-inflammatory cytokine mRNAs in activated T cells in vivo. Mechanistically, SPA could inhibit STAT1/4 and STAT3 phosphorylation, resulting in the differentiation of Th1 and suppression of Th17 cells, respectively. In the presence of CD3/CD28 expression, STAT1/4 and STAT3 were activated but suppressed by SPA, which was responsible for the augmentation of Th1 and Th17 differentiation. This result showed that SPA can effectively modulate the JAK/STAT pathway by suppressing Th1 and Th17 differentiation, thus preventing asthma. The present study reveals the novel immunomodulatory activity of SPA and highlights the importance of further investigating the effects of SPA on asthma.

Loss of direct adrenergic innervation after peripheral nerve injury causes lymph node expansion through IFN-γ

Peripheral nerve injury can cause debilitating disease and immune cell-mediated destruction of the affected nerve. While the focus has been on the nerve-regenerative response, the effect of loss of innervation on lymph node function is unclear. Here, we show that the popliteal lymph node (popLN) receives direct neural input from the sciatic nerve and that sciatic denervation causes lymph node expansion. Loss of sympathetic, adrenergic tone induces the expression of IFN-γ in LN CD8 T cells, which is responsible for LN expansion. Surgery-induced IFN-γ expression and expansion can be rescued by β2 adrenergic receptor agonists but not sensory nerve agonists. These data demonstrate the mechanisms governing the pro-inflammatory effect of loss of direct adrenergic input on lymph node function.

SARS-CoV-2 Infection and Guillain-Barré Syndrome

Severe acute respiratory syndrome coronavirus strain 2 (SARS-CoV-2) is a beta-coronavirus that emerged as a global threat and caused a pandemic following its first outbreak in Wuhan, China, in late 2019. SARS-CoV-2 causes COVID-19, a disease ranging from relatively mild to severe illness. Older people and those with many serious underlying medical conditions such as diabetes, heart or lung conditions are at higher risk for developing severe complications from COVID-19 illness. SARS-CoV-2 infections of adults can lead to neurological complications ranging from headaches, loss of taste and smell, to Guillain-Barré syndrome, an autoimmune disease characterized by neurological deficits. Herein we attempt to describe the neurological manifestations of SARS-CoV2 infection with a special focus on Guillain-Barré syndrome.

Assessment of Expression of SOCS Genes in Acquired Immune-Mediated Polyneuropathies

Acquired immune-mediated polyneuropathies are classified to some subtypes among them are acute and chronic inflammatory demyelinating polyradiculoneuropathies (AIDP and CIDP). These two conditions share some common signs and underlying mechanisms. Based on the roles of Suppressor of cytokine signaling (SOCS) genes in the modulation of immune system reactions, these genes might be involved in the pathogenesis of these conditions. We evaluated expression of SOCS1-3 and SOCS5 genes in the leukocytes of 32 cases of CIDP, 19 cases of AIDP and 40 age- and sex-matched controls using real time PCR method. The Bayesian regression model was used to estimate differences in mean values of genes expressions between cases and control group. Expression levels of SOCS1 and SOCS2 were significantly lower in male patients compared with controls. This sex-specific pattern was also observed for SOCS3 down-regulation. Based on the area under curve values in Receiver Operating Characteristics (ROC) curve, diagnostic powers of SOCS1, SOCS2, SOCS3 and SOCS5 genes in the mentioned disorder were 0.61, 0.73, 0.68 and 0.58, respectively. Expression of none of genes was correlated with age of enrolled cases. The current study shows evidences for participation of SOCS genes in the pathophysiology of acquired immune-mediated polyneuropathies.

Guillain-Barré syndrome associated with Covid-19: A close relationship or just a coincidence? (Review)

Several neurological complications affecting the central and peripheral nervous system were described secondary to COVID-19 infection such as hyposmia, headache, nausea, impaired consciousness, psychosis, neurocognitive syndromes and even cerebrovascular accidents. The mechanism of these complications is not fully understood, but heterogenous mechanisms such as cytokine storm, secondary hypercoagulability and direct neurotropism of the virus are thought to be involved. Guillain-Barré syndrome is a heterogeneous disease that frequently follows a bacterial or viral infection. During the ongoing SARS-CoV-2 pandemic, several isolated case reports and case series have suggested an association between this viral infection and the occurrence of Guillain-Barré syndrome. The main mechanism of Guillain-Barré syndrome is probably post-viral dysregulation of the immune system generated by SARS-CoV-2. The clinical characteristics and disease evolution seem to be similar to those observed in Guillain-Barré syndrome secondary to other etiologies. The aim of the present review is to summarize the relevant literature regarding SARS-CoV-2-related Guillain-Barré syndrome.

Nuclear factor kappa B inhibitor suppresses experimental autoimmune neuritis in mice via declining macrophages polarization to M1 type

Guillain-Barré syndrome (GBS) is an acute inflammatory and immune-mediated demyelinating disease of the peripheral nervous system (PNS). Macrophages play a central role in its animal model, experimental autoimmune neuritis (EAN), which has been well accepted. Additionally, nuclear factor (NF)-κB inhibitors have been used to treat cancers and have shown beneficial effects. Here, we investigated the therapeutic effect of M2 macrophage and the NF-κB pathway's correlation with macrophage activation in EAN in C57BL/6 mice. We demonstrate that M2 macrophage transfusion could alleviate the clinical symptoms of EAN by reducing the proportion of M1 macrophage in the peak period, inhibiting the phosphorylation of NF-κB p65. The NF-κB inhibitor (BAY-11-7082) could alleviate the clinical symptoms of EAN and shorten the duration of symptoms by reducing the proportion of M1 macrophages and the expression of proinflammatory cytokines. Consequently, BAY-11-7082 exhibits strong potential as a therapeutic strategy for ameliorating EAN by influencing the balance of M1/M2 macrophages and inflammatory cytokines.

SARS-CoV-2 Infection and Guillain-Barré Syndrome: A Review on Potential Pathogenic Mechanisms

Since December 2019, the world has been facing an outbreak of a new disease called coronavirus disease 2019 (COVID-19). The COVID-19 pandemic is caused by a novel beta-coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The SARS-CoV-2 infection mainly affects the respiratory system. Recently, there have been some reports of extra-respiratory symptoms such as neurological manifestations in COVID-19. According to the increasing reports of Guillain-Barré syndrome following COVID-19, we mainly focused on SARS-CoV-2 infection and Guillain-Barré syndrome in this review. We tried to explain the possibility of a relationship between SARS-CoV-2 infection and Guillain-Barré syndrome and potential pathogenic mechanisms based on current and past knowledge.

Inhibition of TLR4 signaling protects mice from sensory and motor dysfunction in an animal model of autoimmune peripheral neuropathy

BACKGROUND

While the etiology remains elusive, macrophages and T cells in peripheral nerves are considered as effector cells mediating autoimmune peripheral neuropathy (APN), such as Guillain-Barre syndrome. By recognizing both pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) signals, TLRs play a central role in the initiation of both innate and adaptive immune responses. In this study, we aimed to understand the involvement of TLR4 in the pathogenesis of APN and explore the potential of TLR4 as a drug target for therapeutic use.

METHODS

APN was induced by a partial ligation on one of the sciatic nerves in B7.2 (L31) transgenic mice which possess a predisposed inflammatory background. APN pathology and neurological function were evaluated on the other non-injured sciatic nerve.

RESULTS

TLR4 and its endogenous ligand HMGB1 were highly expressed in L31 mice, in circulating immune cells and in peripheral nerves. Enhanced TLR4 signaling was blocked with TAK 242, a selective TLR4 inhibitor, before and after disease onset. Intraperitoneal administration of TAK 242 not only inhibited monocyte, macrophage and CD8⁺ T cell activation, but also reduced the release of pro-inflammatory cytokines. TAK 242 protected mice from severe myelin and axonal loss, resulting in a remarkable improvement in mouse motor and sensory functions. TAK 242 was effective in alleviating the disease in both preventive and reversal paradigms.

CONCLUSION

The study identified the critical contribution of TLR4-mediated macrophage activation in disease course and provided strong evidence to support TLR4 as a useful drug target for treating inflammatory autoimmune neuropathy.

The therapeutic effects of ginkgolides in Guillain-Barré syndrome and experimental autoimmune neuritis

BACKGROUND

Guillain-Barré syndrome (GBS) is an acquired immune-mediated inflammatory peripheral neuropathy. The immune regulation of ginkgolides have been revealed in recent years. We herein investigate the potential therapeutic effects of ginkgolides both on GBS and its animal model, experimental autoimmune neuritis (EAN).

METHODS

EAN in C57BL/6 mice induced by subcutaneous injection with peripheral nerve myelin P0 protein peptide 180-199 (P0 peptide) were treated with ginkgolides at three different doses. GBS patients were randomly divided into two groups, the experimental group and the control group. The experimental group were treated with ginkgolides as soon as diagnosed.

RESULTS

Our data indicated that ginkgolides administration daily ameliorated the score of EAN and delayed the peak of disease in EAN mice. Ginkgolides also down-regulated the proportions of T helper (Th) 17 cells in EAN spleens. Furthermore, we also found that administration of ginkgolides significantly decreased the levels of interferon (IFN)-γ and interleukin-12 (IL)-12 in GBS patients.

CONCLUSIONS

Our results suggested that ginkgolides ameliorated the clinical score of EAN through down-regulating the proportions of Th 17 cells. Ginkgolides also suppressed inflammation response by decreasing pro-inflammatory cytokines IFN-γ and IL-12, suggesting ginkgolides had potential therapeutic effects on GBS patients and EAN in the future.

Immune function changes of the IDPN-induced Tourette syndrome rat model

There may be immunologic alternations during Tourette syndrome (TS) development. This study aimed to determine the immune function changes in different aspects (spleen or thymus index, plasma cytokines, and T cell) in an 3,3'-iminodipropionitrile (IDPN)-induced rat model of TS. Male Sprague-Dawley rats were assigned to control and TS groups. The control group received intraperitoneal infections of normal saline (5 ml kg^-1  day^-1 ), and the TS rats were injected with IDPN (150 mg kg^-1  day^-1 ). The spleen and thymus indices were calculated. The expression of anti-inflammatory cytokines and inflammatory cytokines TNF-α, in peripheral blood were measured by ELISA and Western blotting. The proportion of CD3+, CD4+, CD8+, Treg, Th1, and Th2 cells were determined by fluorescence-activated cell sorting analysis. After 1 week of IDPN treatment, TS rats had decreased spleen and thymus weights versus control. The plasma levels of IL-4, IL-10, IL-12, IFN-γ, and TNF-α were significantly increased, while no significant difference in TGF-β was found. Flow cytometry analysis demonstrated that TS rats had significantly reduced CD3+ and CD4+ cells in spleen, without any change in the proportion of CD8+ cells. Furthermore, the ratio of Treg cells (CD4+/CD25+/FoxP3+) was decreased in TS rats; simultaneously, Th1 cells (CD4+/IFN-γ+) and Th2 cells (CD4+/IL4+) were dramatically increased. Together, IDPN can trigger immune dysfunction through impairment of matured Th cells, in particular for the Treg subset.

Role of Ginkgolides in the Inflammatory Immune Response of Neurological Diseases: A Review of Current Literatures

The inflammatory immune response (IIR) is a physiological or excessive systemic response, induced by inflammatory immune cells according to changes in the internal and external environments. An excessive IIR is the pathological basis for the generation and development of neurological diseases. Ginkgolides are one of the important medicinal ingredients in Ginkgo biloba. Many studies have verified that ginkgolides have anti-platelet-activating, anti-apoptotic, anti-oxidative, neurotrophic, and neuroimmunomodulatory effects. Inflammatory immunomodulation is mediated by inhibition of the mitogen-activated protein kinase (MAPK) and nuclear factor-kappa B (NF-κB) signaling pathways. They also inhibit the platelet-activating factor (PAF)-mediated signal transduction to attenuate the inflammatory response. Herein, we reviewed the studies on the roles of ginkgolides in inflammatory immunomodulation and suggested its potential role in novel treatments for neurological diseases.

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.

Role of Resolvins in the Inflammatory Resolution of Neurological Diseases

The occurrence of neurological diseases including neurodegenerative disorders, neuroimmune diseases, and cerebrovascular disorders is closely related to neuroinflammation. Inflammation is a response against infection or injury. Genetic abnormalities, the aging process, or environmental factors can lead to dysregulation of the inflammatory response. Our immune system can cause massive damage when the inflammatory response becomes dysregulated. Inflammatory resolution is an effective process that terminates the inflammatory response to maintain health. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are omega-three polyunsaturated fatty acids that play a crucial regulatory role in the development of inflammation. Resolvins (Rvs) derived from EPA and DHA constitute the Rvs E and Rvs D series, respectively. Numerous studies on the effect of Rvs over inflammation using animal models reveal that they have both anti-inflammatory and pro-resolving capabilities. Here, we review the current knowledge on the classification, biosynthesis, receptors, mechanisms of action, and role of Rvs in neurological diseases.

The dynamic expression of canonical Wnt/β-catenin signalling pathway in the pathologic process of experimental autoimmune neuritis

Background: Guillain-Barré syndrome (GBS), an autoimmune disease and an acute inflammation disorder, is currently the most frequent cause of acute flaccid paralysis worldwide. EAN, an animal model of GBS, is a CD4+ T cell-mediated autoimmune disease of the PNS. Wnt/β-catenin signals are critically important to several fundamental aspects of peripheral nerve development and play a crucial role in Schwann cell proliferation. Here, we investigate the role of Wnt/β-catenin signalling cascades in EAN rats.Methods: 28 male Lewis rats weighing 170 ± 10 g were randomly divided into control group (n = 7) and EAN groups (Early group; Peak group and Recovery group. n = 7 per group). EAN rats were immunized with P2_57-81 peptide; weighed daily, and the neurologic signs of EAN were evaluated every day. The sciatic nerve was taken on the days 10, 17, and 30 p.i. for H&E staining, transmission electron microscopy and immunohistochemical staining; blood samples were collected weekly from caudal vein to detect IFN-γ, IL-4, TGF-β1; and the sciatic nerve was taken to examinate the dynamics expression of Wnt/β-catenin pathway molecules.Results: In our study, we chose tail-root injection to better model GBS. Moreover, we observed that IFN-γ levels paralleled clinical EAN, and the levels of TGF-β1 and IL-4 gradually increased and peaked in the recovery phase. In addition, we have shown that canonical Wnt signalling is upregulated and reached a peak in the late recovery phase.Conclusion: Our findings suggest that Wnt/β-catenin signalling is associated with the promotion of remyelination in EAN rats.

Effect of fasudil on experimental autoimmune neuritis and its mechanisms of action

This study aimed to investigate the therapeutic effect of fasudil on treating experimental autoimmune neuritis (EAN). Twenty-four EAN mice were randomly assigned to fasudil treatment (Fasudil group) or saline treatment (EAN model group) for 28 days. Clinical symptom score was evaluated every other day; inflammatory cell infiltration, demyelination, anti-myelin basic protein (MBP), inflammatory cytokines, inducible nitric oxide synthase (iNOS), and arginase-1 were detected in sciatic nerves at day 28. Th1, Th2, Th17, and Tregs proportions in splenocytes were detected at day 28. Clinical symptom score was found to be attenuated in the Fasudil group compared to the EAN model group from day 12 to day 28. Sciatic nerve inflammatory cell counts by HE staining and demyelination by luxol fast blue staining were both reduced, while MBP was increased in the Fasudil group compared to the EAN model group at day 28. Interferon γ (IFN-γ) and interleukin (IL)-17 were reduced, while IL-4 and IL-10 were elevated in the Fasudil group at day 28. Sciatic nerve M1 macrophages marker iNOS was decreased while M2 macrophages marker arginase-1 was increased in the Fasudil group at day 28. CD4⁺IFN-γ⁺ (Th1) and CD4⁺IL-17⁺ (Th17) cell proportions were both decreased, CD4⁺IL-4⁺ (Th2) cell proportion was similar, while CD25+FOXP3+ (Treg) cell proportion in splenocytes was increased in the Fasudil group. In summary, fasudil presented a good therapeutic effect for treating EAN by attenuating Th1/Th17 cells and promoting Tregs activation as well as M2 macrophages polarization.

Interleukin-6 signaling pathway involved in major depressive disorder: selective serotonin reuptake inhibitor regulates IL-6 pathway

Background

Evidence indicates that pro-inflammatory Th17 and Th1 cells are involved in major depressive disorder (MDD) pathogenesis. Development of Th17 and Th1 are regulated by IL-6 and IFN-γ, respectively. In this study, the levels of IL-6 and IFN-γ, and mRNA expression of related signaling components and, Th17/Th1 transcription factors were investigated in MDD patients with/without selective serotonin reuptake inhibitor (SSRI) medication.

Materials and methods

Forty-six patients and 38 healthy controls (HCs) were recruited. Twenty patients were received the SSRI (sertraline 50–200 mg/day) for at least 1 year, and 26 patients were not received medication. Expression of IL-6R, IFN-γR, JAK1, JAK2, TYK2, STAT1, STAT3, T-bet and RORγt were assessed with Real-Time-PCR. Serum and supernatant levels of IL-6 and IFN-γ were determined using ELISA.

Results and discussion

The serum and supernatant levels of IL-6 were increased in patients without (SSRI−) compared with HCs, while its levels was reduced in SSRI+. Elevated expressions of IL-6R, STAT3 and RORγt were observed in SSRI− compared with HCs. Expressions of IL-6R, STAT3, RORγt and IFN-γR, were decreased in SSRI+ compared to SSRI− patients.

Conclusion

Increased IL-6 involved in MDD, and SSRI regulates IL-6 pathway and IL-6 production. MDD patients may benefit from IL-6/IL-6R targeted therapeutic intervention.

Th17 cells and their cytokines serve as potential therapeutic target in experimental autoimmune neuritis

BACKGROUND

Accumulating evidence has pointed that T helper 17 cells and their cytokines are pathogenic in Guillain-Barré syndrome (GBS). However, little is known concerning the IL-17 expression change trend during the whole course of disease, and whether drugs specially targeting Th17 cells or their cytokines have potential effects on experimental autoimmune neuritis (EAN) is uncertain.

METHODS

We explored the IL-17 and receptor-related orphan receptor-gamma-t (RORγt) expression change trends in EAN rats to identify the stage of effect of Th17 pathway in EAN, and further, we investigated the effect of RORγt inhibitors by assessing clinical score, histological staining, and IL-17 and RORγt expression change trends in serum and tissues.

RESULTS

The expression level of IL-17 and RORγt in serum and tissues increased with the progression of the disease in the EAN group and decreased after the disease reaching its peak. RORγt-IN-1 treatment strikingly reduced the neurological deficits by ameliorating inflammatory cell infiltration, deceased the serum IL-17 and RORγt levels, and further downregulated the expression of IL-17 and RORγt mRNA in spleen, lymphnodes, and sciatic nerve.

CONCLUSIONS

Th17 cells and their cytokines are closely associated with the onset of GBS and the novel RORγt inhibitors may be prospective strategies in treating GBS.

Effects of Treatment with the Hypomethylating Agent 5-aza-2'-deoxycytidine in Murine Type II Collagen-Induced Arthritis

The emerging role of epigenetics in the pathogenesis of autoimmune diseases has recently attracted much interest on the possible use of epigenetic modulators for the prevention and treatment of these diseases. In particular, we and others have shown that drugs that inhibit DNA methylation, such as azacitidine (AZA) and decitabine (DAC), already used for the treatment of acute myeloid leukemia, exert powerful beneficial effects in rodent models of type 1 diabetes, multiple sclerosis, and Guillain Barrè syndrome. Along this line of research, we have presently studied the effects of DAC in a murine model of rheumatoid arthritis induced by type II collagen and have demonstrated that DAC administration was associated with a significant amelioration of the clinical condition, along with in vivo and ex vivo modification of the immunological profile of the so-treated mice, that exhibited a diminished production of Th1 and Th17 pro-inflammatory cytokines and reduction of anti-type II collagen autoantibodies.

The effects of IVIg therapy on serum levels of neuropeptide Y and cytokines in Guillain-Barré syndrome

BACKGROUND

Guillain-Barré syndrome (GBS) is a common acute immune-mediated inflammatory disorder affecting the peripheral nervous system (PNS) of humans. Studies in humans and in animal models revealed that neuropeptide Y (NPY) levels are altered in some neurodegenerative and neuroimmune disorders. Herein, we investigated the levels of NPY and cytokines in the serum of GBS patients and explored the roles of NPY in the disease severity and its short-term prognosis.

METHODS

Twenty patients with GBS (case group) and twenty healthy individuals (control group) were enrolled in this study. NPY levels were analyzed by enzyme-linked immunosorbent assay (ELISA). The levels of pro- and anti-inflammatory cytokines (including interferon-γ (IFN-γ), interleukin (IL)-4, IL-10, IL-12p70, IL-17A, and tumor necrosis factor-α (TNF-α)) were analyzed using cytometric beads array (CBA). The clinical characteristics, disease severity, and short-term prognosis were compared between the two groups.

RESULTS

Compared with the control group, the levels of NPY and cytokines were significantly increased in the serum of patients with GBS. NPY levels in the serum of GBS patients were correlated with the disease severity.

CONCLUSION

Our results suggest that NPY and cytokines are involved in the pathogenesis of GBS. The levels of NPY can help to predict the severity of the disease.

Intravenous immunoglobulin promotes the proliferation of CD4+CD25+ Foxp3+ regulatory T cells and the cytokines secretion in patients with Guillain-Barré syndrome in vitro

Intravenous immunoglobulin (IVIg) serves as the first line therapy in Guillain-Barré syndrome (GBS), however, its action mechanism remains unknown. We hereby stimulated peripheral blood mononuclear cells (PBMCs) from patients with GBS and healthy controls using IVIg and an IgG-derived natural Treg epitopes, namely Tregitopes. Our results showed that IVIg significantly promoted both the expansion of CD4⁺CD25⁺Foxp3⁺ regulatory T cells (Tregs) and secretion of IL-10 and TGF-β1 while Tregitopes promoted secretion of IL-10 and TGF-β1 only. Further study is necessary to elucidate the molecular mechanism of IVIg and Tregitopes on Tregs and the secretion of IL-10 and TGF-β1 in GBS.

Roles of Neuropeptide Y in Neurodegenerative and Neuroimmune Diseases

Neuropeptide Y (NPY) is a neurotransmitter or neuromodulator that mainly exists in the nervous system. It plays a neuroprotective role in organisms and widely participates in the regulation of various physiological processes in vivo. Studies in both humans and animal models have been revealed that NPY levels are altered in some neurodegenerative and neuroimmune disorders. NPY plays various roles in these diseases, such as exerting a neuroprotective effect, increasing trophic support, decreasing excitotoxicity, regulating calcium homeostasis, and attenuating neuroinflammation. In this review, we will focus on the roles of NPY in the pathological mechanisms of neurodegenerative and neuroimmune diseases, highlighting NPY as a potential therapeutic target in these diseases.

Alnus Sibirica Extracts Suppress the Expression of Inflammatory Cytokines Induced by Lipopolysaccharides, Tumor Necrosis Factor-α, and Interferon-γ in Human Dermal Fibroblasts

The effects of Alnus sibirica (AS) extracts on cytokine expression induced by inflammatory stimulants were examined in human dermal fibroblasts (HDFs) and RAW264.7 cells. The anti-oxidative effect and effect on cell viability of AS extracts were evaluated, and four extracts with the highest anti-oxidative effects were selected. HDFs and RAW264.7 cells were treated with inflammatory stimulants, and the expression of cytokines involved in acute (IL-6 and IL-10) and chronic (IL-18) inflammation, the initiation of the immune response (IL-33), and non-specific immune responses (IL-1β, IL-8, and TNF-α) were determined using a reverse-transcription polymerase chain reaction. LPS increased the expression of all the cytokines, except for IL-18; however, AS extracts, particularly AS2 and AS4, reduced this increase, and TNF-α treatment markedly increased the expression of cytokines related to non-specific immune responses. IFN-γ treatment induced no significant changes, except for increased IL-33 expression in HDFs. AS extracts inhibited the increase in the expression of IL-33 and other cytokines in HDFs. Thus, the exposure of HDFs and RAW264.7 cells to inflammatory stimulants increased the expression of cytokines related to all the inflammatory processes. HDFs are involved not only in simple tissue regeneration but also in inflammatory reactions in the skin. AS2 and AS4 may offer effective therapy for related conditions.

Correspondence: Guillain-Barré syndrome and hemorrhagic fever with renal syndrome

Jiao and colleagues reported a case of hemorrhagic fever with renal syndrome who developed respiratory failure and symmetrical flaccid paralysis of all extremities. Electrophysiology revealed peripheral nerve injuries mainly in axons. They reached a diagnosis of Guillain-Barré syndrome (GBS) associated with hemorrhagic fever with renal syndrome. Although the case is interesting, the diagnosis of GBS in such a patient should be with caution. Critical illness polyneuropathy (CIP) is an important and common differential diagnosis of GBS, especially in intensive care settings. Differentiating CIP from the axonal variants of GBS may be difficult on purely clinical grounds. Albumino-cytologic dissociation in CSF can help differentiate GBS from other disorders.

Transcriptomes in rat sciatic nerves at different stages of experimental autoimmune neuritis determined by RNA sequencing

Guillain-Barré syndrome (GBS) is characterized by acute immune-mediated peripheral neuropathy, which may result in rapidly progressive paralysis and fatal respiratory failure. As the underlying pathological mechanisms of GBS are unclear, we surveyed the transcriptome of rats with experimental autoimmune neuritis (EAN), a model of GBS. Briefly, sciatic nerves on both sides were collected from 8-10-week-old Lewis rats during early (10 days post-induction), peak (19 days) and late neuritis (30 days). Total RNA was sequenced to identify differentially expressed genes. Compared to control rats without induced neuritis, 33 genes were differentially expressed in the early phase (14 up-regulated and 19 down-regulated), with an adjusted P-value < 0·05 and |log₂ fold-change| >1, as were 137 genes in the peak phase (126 up-regulated and 11 down-regulated) and 60 genes in the late phase (58 up-regulated and two down-regulated). Eleven of these genes were common to all stages, suggesting their crucial roles throughout the disease course. Analysis of protein-protein interactions revealed Fos, Ccl2, Itgax and C3 as node genes at different stages. Functional analysis of differentially expressed genes identified biological processes and pathways that are activated as neuritis progresses. This is the first genomewide gene expression study of peripheral nerves in experimental autoimmune neuritis model. Dynamic gene expression and significantly altered biological functions were detected in different phases of the disease, increasing our understanding of the molecular mechanisms underlying EAN and highlighting potential targets for its diagnosis and treatment.

Upregulation of IL-1 Receptor Antagonist in a Mouse Model of Migraine

Migraine is a disorder characterized by attacks of monolateral headaches, often accompanied by nausea, vomiting, and photophobia. Around 30% of patients also report aura symptoms. The cause of the aura is believed to be related to the cortical spreading depression (CSD), a wave of neuronal and glial depolarization originating in the occipital cortex, followed by temporary neuronal silencing. During a migraine attack, increased expression of inflammatory mediators, along with a decrease in the expression of anti-inflammatory genes, have been observed. The aim of this study was to evaluate the expression of inflammatory genes, in particular that of IL-1 receptor antagonist (IL-1RN), following CSD in a mouse model of familial hemiplegic migraine type 1 (FHM-1). We show here that the expression of IL-1RN was upregulated after the CSD, suggesting a possible attempt to modulate the inflammatory response. This study allows researchers to better understand the development of the disease and aids in the search for new therapeutic strategies in migraine.

Peripheral Blood and Cerebrospinal Fluid Cytokine Levels in Guillain Barré Syndrome: A Systematic Review and Meta-Analysis

Background: Guillain Barré Syndrome (GBS) is an autoimmune disorder caused by the immune-mediated damage of the peripheral nervous system. Increasing evidence suggests that inflammatory cytokines are important mediators for the onset and progression of GBS. A number of clinical studies have demonstrated elevated levels of T helper-1 (Th1-), Th2-, and Th17-related cytokines in patients with GBS; however, the results were inconsistent across studies.

Methods: We performed a systematic review and a meta-analysis of studies comparing the levels of inflammatory cytokines in the cerebrospinal fluid and peripheral blood between patients with GBS and healthy individuals, using Comprehensive Meta-Analysis Version 2 software. A database search identified 30 studies comprising 1,302 patients with GBS and 1,073 healthy controls.

Results: The random-effects meta-analysis demonstrated that peripheral blood tumor necrosis factor-α (Hedges g, 1.544; 95% confidence interval (CI), 0.923–2.165; p < 0.001), interleukin-1β (IL-1β; Hedges g, 0.678; 95% CI, 0.183–1.172; p = 0.007), IL-6 (Hedges g, 0.630; 95% CI, 0.100–1.160; p = 0.02), IL-4 (Hedges g, 0.822; 95% CI, 0.220–1.423; p = 0.007), IL-17 (Hedges g, 1.452; 95% CI, 0.331–2.573; p = 0.011), interferon-γ (Hedges g, 1.104; 95% CI, 0.490–1.719; p < 0.001), and C-reactive protein (Hedges g, 0.909; 95% CI, 0.453–1.365; p < 0.001) levels were significantly increased in patients with GBS when compared with healthy controls. Contrastingly, the blood IL-10 and transforming growth factor-β levels were not significantly associated with GBS. Furthermore, the meta-analysis found that cerebrospinal fluid IL-17 levels were significantly associated with GBS (Hedges g, 1.882; 95% CI, 0.104–3.661; p = 0.038).

Conclusion: Altogether, our results clarified the circulating inflammatory cytokine profile in patients with GBS, and revealed that Th1-, Th2-, and Th17-related cytokines were highly elevated in the GBS patients, suggesting the potential use of these cytokines as biomarkers for GBS.