IL-23/IL-17 immune axis in Guillain Barré Syndrome: Exploring newer vistas for understanding pathobiology and therapeutic implications

Current Biomarker Strategies in Autoimmune Neuromuscular Diseases

Inflammatory neuromuscular disorders encompass a diverse group of immune-mediated diseases with varying clinical manifestations and treatment responses. The identification of specific biomarkers has the potential to provide valuable insights into disease pathogenesis, aid in accurate diagnosis, predict disease course, and monitor treatment efficacy. However, the rarity and heterogeneity of these disorders pose significant challenges in the identification and implementation of reliable biomarkers. Here, we aim to provide a comprehensive review of biomarkers currently established in Guillain-Barré syndrome (GBS), chronic inflammatory demyelinating polyneuropathy (CIDP), myasthenia gravis (MG), and idiopathic inflammatory myopathy (IIM). It highlights the existing biomarkers in these disorders, including diagnostic, prognostic, predictive and monitoring biomarkers, while emphasizing the unmet need for additional specific biomarkers. The limitations and challenges associated with the current biomarkers are discussed, and the potential implications for disease management and personalized treatment strategies are explored. Collectively, biomarkers have the potential to improve the management of inflammatory neuromuscular disorders. However, novel strategies and further research are needed to establish clinically meaningful biomarkers.

Extensive cytokine biomarker analysis in serum of Guillain-Barré syndrome patients

Guillain-Barré syndrome (GBS) is an acute idiopathic polyneuropathy which is related to infection and immune mechanism. The exact pathogenesis of the disease is unknown and treatment is limited. Thus, the purpose of the study is to identify biomarkers of GBS serum and elucidate their involvement in the underlying pathogenesis of GBS that could help to treat GBS more accurately. Antibody array technology was used to detect the expression levels of 440 proteins in serum of 5 GBS group and 5 healthy control group. Sixty-seven differentially expressed proteins (DEPs) were identified by antibody array, among which FoLR1, Legumain, ErbB4, IL-1α, MIP-1α and IGF-2 were down-regulated, while 61 proteins were up-regulated. Bioinformatics analysis indicated that most DEPs were associated with leukocytes, among which IL-1α, SDF-1b, B7-1, CD40, CTLA4, IL-9, MIP-1α and CD40L were in the center of protein-protein interaction (PPI) network. Subsequently, the ability of these DEPs to distinguish GBS from healthy control was further evaluated. CD23 was identified by means of Random Forests Analysis (RFA) and verified by enzyme-linked immunosorbent assay (ELISA). The ROC curve result of CD23 respectively displayed that its sensitivity, specificity and AUC were 0.818, 0.800 and 0.824. We speculate that activation of leukocyte proliferation and migration in circulating blood might be associated with inflammatory recruitment of peripheral nerves, leading to the occurrence and development of GBS, but this conclusion still requires deeper confirmation. More importantly, central proteins may play a pivotal role in the pathogenesis of GBS. In addition, we detected IL-1α, IL-9, and CD23 in the serum of GBS patients for the first time, which may be promising biomarkers for the treatment of GBS.

Sex differences in Guillain Barré syndrome, chronic inflammatory demyelinating polyradiculoneuropathy and experimental autoimmune neuritis

Guillain Barré syndrome (GBS) and its variants, and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP and its variants, are regarded as immune mediated neuropathies. Unlike in many autoimmune disorders, GBS and CIDP are more common in males than females. Sex is not a clear predictor of outcome. Experimental autoimmune neuritis (EAN) is an animal model of these diseases, but there are no studies of the effects of sex in EAN. The pathogenesis of GBS and CIDP involves immune response to non-protein antigens, antigen presentation through non-conventional T cells and, in CIDP with nodopathy, IgG4 antibody responses to antigens. There are some reported sex differences in some of these elements of the immune system and we speculate that these sex differences could contribute to the male predominance of these diseases, and suggest that sex differences in peripheral nerves is a topic worthy of further study.

Effect of Electromyographic Biofeedback Therapy on Muscle Strength Recovery in Children with Guillain-Barré Syndrome

GBS, as an immune-mediated acute inflammatory peripheral neuropathy (Tan and Halpin et al.), with the characteristics of acute onset and rapid progression, is mainly manifested with damages in nerve root and peripheral nerve. The purpose of the study was to investigate the effect of electromyographic biofeedback therapy on muscle strength recovery in children with Guillain–Barré syndrome (GBS). A total of 62 GBS children patients admitted to our hospital from June 2014 to December 2018 were selected and divided into control group (n = 30) and experimental group (n = 32) according to the order of admission. The children patients in the control group received physical therapy combined with occupational therapy (PT + OT), while based on the treatment in the control group, the experimental group children patients were treated with electromyographic biofeedback therapy. After that, the recovery of nerve and muscle at different time points, muscle strength score, gross motor function measure (GMFM) score, and Barthel index (BI) score of the children patients before and after treatment were compared between the two groups. There were no significant differences in the recovery of nerve and muscle of the children patients between the two groups at T₀ and T₁ (P > 0.05), and the recovery of nerve and muscle of the children patients in the experimental group was significantly better than that in the control group at T₂, T₃, and T₄ (P < 0.001); the muscle strength score, GMFM score, and BI score of the children patients in the experimental group were significantly better than those in the control group after treatment (P < 0.001). The application of electromyographic biofeedback therapy for the treatment of GBS can effectively relieve clinical symptoms, promote rapid recovery, and improve treatment efficacy in children patients, which is worthy of application and promotion.

Mechanobiology of immune cells: Messengers, receivers and followers in leishmaniasis aiding synthetic devices

Cytokines are influential molecules which can direct cells behavior. In this review, cytokines are referred as messengers, immune cells which respond to cytokine stimulus are referred as receivers and the immune cells which gets modulated due to their plasticity induced by infectious pathogen leishmania, are referred as followers. The advantage of plasticity of cells is taken by the parasite to switch them from parasite eliminating form to parasite survival favoring form through a process called as reciprocity which is undergone by cytokines, wherein pro-inflammatory to anti-inflammatory switch occur rendering immune cell population to switch their phenotype. Detailed study of this switch can help in identification of important targets which can help in restoring the phenotype to parasite eliminating form and this can be done through synthetic circuit, finding its wider applicability in therapeutics.

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Cytokines as messengers for governing reciprocity in infection.

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Leishmania induces reciprocity modulating the immune cells plasticity.

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Reciprocity of cytokines identifies important target for therapeutics.

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Therapeutic targets aiding the design of synthetic devices to combat infection.

Biomolecule sulphation and novel methylations related to Guillain-Barré syndrome-associated Campylobacter jejuni serotype HS:19

Campylobacter jejuni strains that produce sialylated lipooligosaccharides (LOS) can cause the immune-mediated disease Guillain-Barré syndrome (GBS). The risk of GBS after infection with C. jejuni Penner serotype HS:19 is estimated to be at least six times higher than the average risk. Aside from LOS biosynthesis genes, genomic characteristics that promote an increased risk for GBS following C. jejuni HS:19 infection, remain uncharacterized. We hypothesized that strains with the HS:19 serotype have unique genomic features that explain the increased risk for GBS. We performed genome sequencing, alignments, single nucleotide polymorphisms' analysis and methylome characterization on a subset, and pan-genome analysis on a large number of genomes to compare HS:19 with non-HS:19 C. jejuni genome sequences. Comparison of 36 C. jejuni HS:19 with 874 C. jejuni non-HS:19 genome sequences led to the identification of three single genes and ten clusters containing contiguous genes that were significantly associated with C. jejuni HS:19. One gene cluster of seven genes, localized downstream of the capsular biosynthesis locus, was related to sulphation of biomolecules. This cluster also encoded the campylobacter sialyl transferase Cst-I. Interestingly, sulphated bacterial biomolecules such as polysaccharides can promote immune responses and, therefore, (in the presence of sialic acid) may play a role in the development of GBS. Additional gene clusters included those involved in persistence-mediated pathogenicity and gene clusters involved in restriction-modification systems. Furthermore, characterization of methylomes of two HS:19 strains exhibited novel methylation patterns (5′-CATG-3 and 5′-^m6AGTNNNNNNRTTG-3) that could differentially effect gene-expression patterns of C. jejuni HS:19 strains. Our study provides novel insight into specific genetic features and possible virulence factors of C. jejuni associated with the HS:19 serotype that may explain the increased risk of GBS.

Anti-IL-23 exerted protective effects on cerebral ischemia-reperfusion injury through JAK2/STAT3 signaling pathway

Ischemia-reperfusion frequently occurs in ischemic cerebral vascular disease, during which the inflammatory signaling plays essential roles. The aim of this study was to discover the efficacy of the antibody to a key immune cytokine IL-23 (anti-IL-23) for the therapy of cerebral ischemia-reperfusion injury. We established the cerebral ischemia-reperfusion injury model by middle cerebral artery occlusion (MCAO). Anti-IL-23 injection attenuated lesions indicated by histology study. RT-PCR and Western blot were employed to detect the mRNA and protein expression of JAK2 and STAT3 after anti-IL-23 treatment. ELISA was utilized to measure the levels of MDA (malondialdehyde) and superoxide dismutase (SOD). Moreover, curcumin and IL-6 were implicated in the endogenous intervention of IL-23 signaling in vivo. Our data demonstrated that the treatment of anti-IL-23 might transcriptionally activate the classic immune pathway in the brain. Anti-IL-23 augmented phosphorylation levels of both JAK2 and STAT3, suggesting the amplification signaling of JAK/STAT after exogenous IL-23 intervention. Anti-IL-23 reduced ROS molecules of STAT downstream in the serum and brain. It also alleviated the injury by bringing down levels of MDA and SOD in the serum. JAK2 inhibitor could abolish the effect of anti-IL-23 whereas JAK3 ameliorated the injury. The combination of anti-IL-23 and JAK3i could reduce infarct volume more effectively. In summary, this study indicated that anti-IL-23 had protective effects against cerebral ischemia-reperfusion injury by targeting the immune specific JAK2-STAT3 in JAK/STAT pathway.

Evaluation of Expression of STAT Genes in Immune-Mediated Polyneuropathies

Immune-mediated polyneuropathies are acquired conditions that can be categorized to acute and chronic forms based on the disease course. Although the basic mechanism of these conditions has not been clarified yet, genes that regulate immune responses are putative contributors in their development. In the current study, we assessed expression of signal transducer and activator of transcription (STAT)1-3 and STAT5a genes in peripheral blood of 51 patients and 40 healthy subjects. Expression of STAT1 was higher in female patients compared with female controls (Posterior Beta = 3.622, P = 0.044). The gender*group interaction was significant for this gene which indicates different direction of association in males and females. Expressions of other STAT genes were not different between cases and controls. The diagnostic power of STAT1 in female subjects was estimated to be 0.72 with sensitivity of 68.75% and specificity of 84.62%. There was no significant correlation either between expression of different STAT genes or between their expression and age of study participants. The current study potentiates STAT1 as a putative factor in the pathophysiology of acquired immune-mediated polyneuropathies in females and suggests conduction of further functional studies to elaborate the molecular mechanism of this contribution.

Fulminant Guillain-Barré Syndrome and Spontaneous Intraventricular Hemorrhage: A Case Report and Literature Review

Guillain–Barré syndrome (GBS) is an acute, immune-mediated inflammatory peripheral polyneuropathy that is characterized by flaccid paralysis. A few cases have reported that GBS can be caused by head trauma or neurosurgery, but it has never been associated with intraventricular hemorrhage. Here, we report an uncommon case of fulminant GBS that occurred after spontaneous intraventricular hemorrhage. A 73-year-old woman was admitted to the hospital after sudden unconsciousness and vomiting. A head computed tomography (CT) scan following the incident showed a newly developed intraventricular hemorrhage, which led to an immediate ventriculostomy. After 5 days, the endotracheal tube was removed. Two days later, the external ventricular drainage tube was also removed. At this time, the patient was alert and the neurological examination was normal. However, the patient suddenly presented with acute respiratory failure and bilateral limb weakness 3 days later. An analysis of the patient’s cerebrospinal fluid (CSF) revealed that albuminocytologic dissociation was present. The patient was treated with intravenous immunoglobulin (0.4 g/kg/day) for 5 days. Despite timely medical intervention in the hospital, the patient passed away 2 months later. After a cerebral hemorrhagic injury, limb and respiratory muscle weakness can occur on occasion in the ICU. In this context, the potential involvement of GBS should not be ignored. Importantly, the pathogenic mechanism of GBS has been discussed for over a century, and it still remains a mystery. We speculate that the TLR4/NF-κB signaling pathway may be involved in the pathogenesis of GBS following intraventricular hemorrhage. The prognosis of most patients with GBS is usually good, but cerebral hemorrhage and mechanical ventilation may serve as risk factors that exacerbate the condition. This case is reported to remind clinicians to consider the possibility of GBS when patients present limb and respiratory muscle weakness after intraventricular hemorrhage, and to provide a starting point to discuss potential mechanisms of GBS after intraventricular hemorrhage.

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.

Riemerella anatipestifer infection in ducks induces IL-17A production, but not IL-23p19

R. anatipestifer (RA) is one of the most harmful bacterial pathogens affecting the duck industry, and infection is associated with the production of proinflammatory cytokines, including IL-17A. Another proinflammatory cytokine, IL-23, is critical for the development of Th17 cells, which produce IL-17. However, IL-23 roles have not been studied in this infection. Here, we describe the identification and mRNA expression analysis of duck IL-23p19 (duIL-23p19) in splenic lymphocytes and macrophages stimulated with killed RA and in spleens of RA-infected ducks. Expression of duIL-23p19 transcript identified in this study was relatively high in livers of healthy ducks and was upregulated in mitogen-activated splenic lymphocytes as well as in splenic lymphocytes and macrophages stimulated with killed RA. In spleens of RA-infected ducks, expression levels of duIL-23p19 transcript were unchanged at all time points except on days 4 and 7 post-infection; however, duIL-17A and IL-17F expression levels were upregulated in both spleens of RA-infected ducks and splenic lymphocytes and macrophages stimulated with killed RA. In sera collected at 24 h after this infection, duIL-23p19 expression levels were unchanged, whereas IL-17A significantly upregulated. These results suggest that IL-23p19 does not play a critical role in the IL-17A response in early stages of RA-infected ducks.

Visceral white adipose tissue and serum proteomic alternations in metabolically healthy obese patients undergoing bariatric surgery

Metabolically healthy obesity is characterized as a comorbidity-free obesity status, however the exact pathogenetic mechanisms implicated in its transition to unhealthy obesity have not yet been unveiled. Our aim was to investigate the effect of metabolic health on the proteomic profile both in serum and visceral fat of morbidly obese subjects. 28 patients undergoing bariatric surgery were prospectively enrolled. They were divided into two groups: metabolically healthy (MHO, n = 18) and unhealthy (MUO, n = 10) obese patients. 30 biomarkers were measured in serum and visceral adipose tissue with the use of targeted proteomic analysis (Luminex assays). TNF weak inducer of apoptosis (TWEAK) (p = 0.043), TNF related apoptosis inducing ligand (TRAIL) (p = 0.037), Growth differentiation factor-15 (GDF-15) (p = 0.04), Resistin (RETN) (p = 0.047), Matrix metalloproteinase-9 (MMP-9) (p = 0.011) and C-terminal telopeptide (ICTP) (p = 0.022) were up-regulated in the MUO group in the visceral white adipose tissue. Moreover, C-C motif ligand-3 (CCL-3) (p = 0.056), Interleukin-20 (IL-20) (p = 0.04), Prokineticin-1 (PROK-1) (p = 0.028) and TWEAK (p = 0.016) were found to be suppressed in the serum of MHO group. Significant correlations between serum and adipose tissue levels of certain cytokines were also observed, while 16 biomarkers were associated with BMI. Our results indicate metabolic health substantially attenuates the expression of TWEAK, TRAIL, GDF-15, RETN, MMP-9 and ICTP expression locally, in the visceral white adipose tissue, and the expression of CCL-3, IL-20, PROK-1 and TWEAK in the peripheral blood. Intriguingly, different cytokines -except for TWEAK- are up-regulated in each site, suggesting that obesity is not a homogenous but a multi-dimensional disease.

Targeting the IL-23/IL-17 Pathway in Psoriasis: the Search for the Good, the Bad and the Ugly

New promising treatments have been developed for psoriasis that target different parts of the interleukin (IL)-23/IL-17 pathway. This approach is believed to be more disease specific, and sparing the T helper 1 pathway might prevent serious long-term adverse events. Moreover, superior Psoriasis Area and Severity Index improvements are observed, which has redefined treatment goals in psoriasis. The new molecules can be divided into different categories, according to the target: blocking agents can target the upstream cytokine IL-23 or the downstream IL-17. In the latter, a variety of targets exist, such as the ligands IL-17A and IL-17F, or a combination thereof, or a subunit of the receptor, IL-17RA. Each target seems to have its own set of advantages and pitfalls, which will impact the treatment decision in clinical practice. In this review, we summarize the current knowledge on the different inhibitors of the IL-23/IL-17 pathway. Furthermore, we briefly discuss the role of IL-17 in other diseases and comorbidities. Finally, we discuss how comprehensive knowledge is needed for the prescribing physician in order to make the most appropriate therapeutic choice for each individual patient.

Comprehensive cytokine profiling provides evidence for a multi-lineage Th responses in Guillain Barré Syndrome

Guillain Barré Syndrome (GBS) is one of the commonest acquired immune-mediated neuropathies, often preceded by infections. Although cellular immune responses are shown to substantially account for the pathophysiology of GBS, the precise mechanistic basis of risk and disease course remains enigmatic till date. Cytokines are best known for their abilities to drive cellular immunity and inflammation through their co-ordinated actions. Data obtained from clinical and animal model studies suggest important implications of some of the cytokines in the progression and recovery of GBS. However, these studies were performed on few cytokines and small set of GBS patients, thereby lacking a complete understanding of the patterns of association of cytokines representing Th1, Th2, and Th17 responses with GBS. We studied 65 well-characterized GBS patients and 73 age- and sex-matched healthy controls. A panel of 15 cytokines representing Th1, Th2 and Th17 pathways was assayed using Multiplex Suspension Array platform. Plasma levels of five cytokines were found to be altered in GBS patients compared to healthy control subjects: (i) IL-1β exhibited reduced levels, and (ii) IFN-γ, IL-4, IL-21 and IL-33 were elevated in GBS patients. The most important finding of this study was up-regulated expression of IL-21 and IL-33 in patients with GBS. Given the role of IL-33 as an alarmin, the elevated level of this cytokine provides important indication about a much broader role of cytokines in GBS. This study also provides evidence towards a multi-lineage Th cells (Th1, Th2 and Th17) associated cytokine responses in the pathophysiology of GBS.