Inflammation and autoimmune myasthenia gravis

Decoding myasthenia gravis: advanced diagnosis with infrared spectroscopy and machine learning

Myasthenia Gravis (MG) is a rare neurological disease. Although there are intensive efforts, the underlying mechanism of MG still has not been fully elucidated, and early diagnosis is still a question mark. Diagnostic paraclinical tests are also time-consuming, burden patients financially, and sometimes all test results can be negative. Therefore, rapid, cost-effective novel methods are essential for the early accurate diagnosis of MG. Here, we aimed to determine MG-induced spectral biomarkers from blood serum using infrared spectroscopy. Furthermore, infrared spectroscopy coupled with multivariate analysis methods e.g., principal component analysis (PCA), support vector machine (SVM), discriminant analysis and Neural Network Classifier were used for rapid MG diagnosis. The detailed spectral characterization studies revealed significant increases in lipid peroxidation; saturated lipid, protein, and DNA concentrations; protein phosphorylation; PO2-asym + sym /protein and PO2-sym/lipid ratios; as well as structural changes in protein with a significant decrease in lipid dynamics. All these spectral parameters can be used as biomarkers for MG diagnosis and also in MG therapy. Furthermore, MG was diagnosed with 100% accuracy, sensitivity and specificity values by infrared spectroscopy coupled with multivariate analysis methods. In conclusion, FTIR spectroscopy coupled with machine learning technology is advancing towards clinical translation as a rapid, low-cost, sensitive novel approach for MG diagnosis.

Telitacicept: A novel horizon in targeting autoimmunity and rheumatic diseases

BLyS and APRIL have the capability to bind to B cells within the body, allowing these cells to evade elimination when they should naturally be removed. While BLyS primarily plays a role in B cell development and maturation, APRIL is linked to B cell activation and the secretion of antibodies. Thus, in theory, inhibiting BLyS or APRIL could diminish the population of aberrant B cells that contribute to SLE and reduce disease activity in patients. Telitacicept functions by binding to and neutralizing the activities of both BLyS and APRIL, thus hindering the maturation and survival of plasma cells and fully developed B cells. The design of telitacicept is distinctive; it is not a monoclonal antibody but a TACI-Fc fusion protein generated through recombinant DNA technology. This fusion involves merging gene segments of the TACI protein, which can target BLyS/APRIL simultaneously, with the Fc gene segment of the human IgG protein. The TACI-Fc fusion protein exhibits the combined characteristics of both proteins. Currently utilized for autoimmune disease treatment, telitacicept is undergoing clinical investigations globally to assess its efficacy in managing various autoimmune conditions. This review consolidates information on the mechanistic actions, dosing regimens, pharmacokinetics, efficacy, and safety profile of telitacicept-a dual-targeted biological agent. It integrates findings from prior experiments and pharmacokinetic analyses in the treatment of RA and SLE, striving to offer a comprehensive overview of telitacicept's research advancements.

FOSL1-mediated LINC01566 negatively regulates CD4+ T-cell activation in myasthenia gravis

BACKGROUND

Myasthenia gravis (MG) is an autoimmune disease characterized by pathogenic antibodies that target structures of the neuromuscular junction. The evidence suggests that the regulation of long noncoding RNAs (lncRNAs) that is mediated by transcription factors (TFs) plays a key role in the pathophysiology of MG. Nevertheless, the detailed molecular mechanisms of lncRNAs in MG remain largely undetermined.

METHODS

Using microarray analysis, we analyzed the lncRNA levels in MG. By bioinformatics analysis, LINC01566 was found to potentially play an important role in MG. First, qRT‒PCR was performed to verify the LINC1566 expressions in MG patients. Then, fluorescence in situ hybridization was conducted to determine the localization of LINC01566 in CD4 + T cells. Finally, the impact of LINC01566 knockdown or overexpression on CD4 + T-cell function was also analyzed using flow cytometry and CCK-8 assay. A dual-luciferase reporter assay was used to validate the binding of the TF FOSL1 to the LINC01566 promoter.

RESULTS

Based on the lncRNA microarray and differential expression analyses, we identified 563 differentially expressed (DE) lncRNAs, 450 DE mRNAs and 19 DE TFs in MG. We then constructed a lncRNA-TF-mRNA network. Through network analysis, we found that LINC01566 may play a crucial role in MG by regulating T-cell-related pathways. Further experiments indicated that LINC01566 is expressed at low levels in MG patients. Functionally, LINC01566 is primarily distributed in the nucleus and can facilitate CD4 + T-cell apoptosis and inhibit cell proliferation. Mechanistically, we hypothesized that LINC01566 may negatively regulate the expressions of DUSP3, CCR2, FADD, SIRPB1, LGALS3 and SIRPB1, which are involved in the T-cell activation pathway, to further influence the cellular proliferation and apoptosis in MG. Moreover, we found that the effect of LINC01566 on CD4 + T cells in MG was mediated by the TF FOSL1, and in vitro experiments indicated that FOSL1 can bind to the promoter region of LINC01566.

CONCLUSIONS

In summary, our research revealed the protective roles of LINC01566 in clinical samples and cellular experiments, illustrating the potential roles and mechanism by which FOSL1/LINC01566 negatively regulates CD4 + T-cell activation in MG.

The Application Potential of the Regulation of Tregs Function by Irisin in the Prevention and Treatment of Immune-Related Diseases

Irisin is a muscle factor induced by exercise, generated through the proteolytic cleavage of the membrane protein fibronectin type III domain-containing protein 5 (FNDC-5). Numerous studies have shown that irisin plays a significant role in regulating glucose and lipid metabolism, inhibiting oxidative stress, reducing systemic inflammatory responses, and providing neuroprotection. Additionally, irisin can exert immunomodulatory functions by regulating regulatory T cells (Tregs). Tregs are a highly differentiated subset of mature T cells that play a key role in maintaining self-immune homeostasis and are closely related to infections, inflammation, immune-related diseases, and tumors. Irisin exerts persistent positive effects on Treg cell functions through various mechanisms, including regulating Treg cell differentiation and proliferation, improving their function, modulating the balance of immune cells, increasing the production of anti-inflammatory cytokines, and enhancing metabolic functions, thereby helping to maintain immune homeostasis and prevent immune-related diseases. As an important myokine, irisin interacts with receptors on the cell membrane, activating multiple intracellular signaling pathways to regulate cell metabolism, proliferation, and function. Although the specific receptor for irisin has not been fully identified, integrins are considered potential receptors. Irisin activates various signaling pathways, including AMPK, MAPK, and PI3K/Akt, through integrin receptors, thereby exerting multiple biological effects. These research findings provide important clues for understanding the mechanisms of irisin's action and theoretical basis for its potential applications in metabolic diseases and immunomodulation. This article reviews the relationship between irisin and Tregs, as well as the research progress of irisin in immune-related diseases such as multiple sclerosis, myasthenia gravis, acquired immune deficiency syndrome, type 1 diabetes, sepsis, and rheumatoid arthritis. Studies have revealed that irisin plays an important role in immune regulation by improving the function of Tregs, suggesting its potential application value in the treatment of immune-related diseases.

Serum globulin in children with myasthenia gravis: predicting relapse and prognosis

OBJECTIVE

Serum globulin is associated with inflammatory or immune disorders. However, it has not been established whether it is associated with myasthenia gravis (MG). We investigated the association between globulin with relapse and prognosis in children with MG.

METHODS

A cohort of 148 MG cases and 150 healthy children were retrospectively enrolled from January 2015 to December 2021. Multivariate logistic and Cox regression models were used to analyze the treatment outcomes and recurrence of case group, exploring the influence of globulin.

RESULTS

Compared with the control group, globulin levels in the MG group were slightly increased (t = 7.244, p < 0.001). After a mean follow-up of 2.25 ± 1.05 years, 35 cases relapsed, with a relapse rate of 23.65%. Logistic regression analysis showed that globulin levels at admission [adjusted odds ratio (OR) = 1.233, 95% confidence interval (CI) 1.028-1.472, p = 0.018] were independent risk factors for relapse. Cox regression analysis confirmed that globulin levels at admission affects relapse-free time [adjusted hazard ratio (HR) = 0.552, 95% CI 0.357-0.852, p = 0.007]. Receiver operating characteristic curve determined 25.10 as the optimal cutoff value for globulin. Cox regression showed that high globulin levels (>25.10) at admission (adjusted HR = 0.607, 95% CI 0.383-0.961, p = 0.033) were independent risk factors for poor therapeutic outcomes at follow-up. Ordinal logistic regression showed that globulin affects the treatment plan (OR = 1.445, 95% CI 1.223-1.847, p = 0.014).

CONCLUSIONS

Elevated globulin levels in children with MG on admission predicts a high relapse rate and poor long-term therapeutic efficacies.

Coexistence of Parkinson's disease and myasthenia gravis: A case report and literature review

The coexistence of Parkinson's disease (PD) and myasthenia gravis (MG) is rare. When similar symptoms of both diseases overlap, it is challenging to make a concomitant diagnosis of PD and MG. The present study describes the case of a patient with concomitant PD and MG. In addition, a systematic literature review was conducted by searching PubMed and Embase for reports on all patients with concomitant PD and MG, which were then grouped and compared according to different preexisting diseases. Finally, a total of 47 cases of concomitant PD and MG (35 men; 12 women), including the present case, were analyzed. The median age of the patients at first diagnosis was 66.59±9.91 years. The interval between the two diseases varied from 2 months to 22 years. Based on the sequential occurrence of these two diseases, the patients were categorized into three groups: The prePD-MG (30 cases), preMG-PD (12 cases), and coPD-MG (5 cases) groups. In the prePD-MG group, the onset age of MG was older and head drop was more common. In the preMG-PD group, the patients were more likely to have comorbid immune diseases.

Increased serum interleukin-41 correlates with disease severity in myasthenia gravis

BACKGROUND

Myasthenia gravis (MG) is an autoimmune disease mediated by pathogenic antibodies produced by abnormally activated B cells, resulting in neuromuscular junction transmission dysfunction. Interleukin-41 (IL-41) is a novel immunomodulatory cytokine that has been implicated in various metabolic, inflammatory, and autoimmune diseases. The role of IL-41 in MG is still unclear up to now, our study aimed to investigate the level of IL-41 in MG patients and its correlation with clinical features and inflammatory indicators.

METHODS

Totally, 60 MG patients and 30 healthy controls (HC) were recruited. Baseline data and laboratory parameters were routinely recorded through electronic medical systems. IL-41 levels were measured by enzyme-linked immunosorbent assay. Proportions of T-cell and B-cell subsets and natural killer cells were analyzed by flow cytometry. The correlation between serum IL-41 and MG related parameters was investigated, and the clinical value of IL-41 in the diagnosis of MG was evaluated by receiver operator characteristic curve (ROC) analysis.

RESULTS

Serum IL-41 levels in MG patients were higher than in HC, and were higher in Myasthenia Gravis Foundation of America (MGFA) III + IV group than that in MGFA I + II group. Serum IL-41 was positively correlated with MG-specific activities of daily living scale (MG-ADL), MGFA classification, platelet to lymphocyte ratio (PLR), and proportion of CD19+ B cells, while it was negatively correlated with high-sensitive C-reactive protein (hs-CRP) and circulatory plasma cells in MG patients. Serum IL-41 levels increased in patients who were treated with efgartigimod during the first cycle of therapy. However, compared to disease initiation, serum IL-41 levels decreased when clinical features steadily improved. ROC analysis showed that IL-41 had a diagnostic value for MG.

CONCLUSION

The present findings suggested that serum IL-41 was increased in MG patients and was positively associated with the severity of the disease. IL-41 may be essential to the immunopathological mechanism of MG and a potential biomarker for MG.

Dynamic changes of peripheral inflammatory markers link with disease severity and predict short-term poor outcome of myasthenia gravis

The relationship between peripheral inflammatory markers, their dynamic changes, and the disease severity of myasthenia gravis (MG) is still not fully understood. Besides, the possibility of using it to predict the short-term poor outcome of MG patients have not been demonstrated. This study aims to investigate the relationship between peripheral inflammatory markers and their dynamic changes with Myasthenia Gravis Foundation of America (MGFA) classification (primary outcome) and predict the short-term poor outcome (secondary outcome) in MG patients. The study retrospectively enrolled 154 MG patients from June 2016 to December 2021. The logistic regression was used to investigate the relationship of inflammatory markers with MGFA classification and determine the factors for model construction presented in a nomogram. Finally, net reclassification improvement (NRI) and integrated discrimination improvement (IDI) were utilized to evaluate the incremental capacity. Logistic regression revealed significant associations between neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), aggregate index of systemic inflammation (AISI) and MGFA classification (p = 0.013, p = 0.032, p = 0.017, respectively). Incorporating dynamic changes of inflammatory markers into multivariable models improved their discriminatory capacity of disease severity, with significant improvements observed for NLR, systemic immune-inflammation index (SII) and AISI in NRI and IDI. Additionally, AISI was statistically associated with short-term poor outcome and a prediction model incorporating dynamic changes of inflammatory markers was constructed with the area under curve (AUC) of 0.953, presented in a nomograph. The inflammatory markers demonstrate significant associations with disease severity and AISI could be regarded as a possible and easily available predictive biomarker for short-term poor outcome in MG patients.

A new gene signature associated with disulfidptosis that forecasts myasthenia gravis and suggests infiltration of immune microenvironment in thymoma patients

Introduction

The mechanism of thymoma-associated myasthenia gravis (TAMG) is currently unknown, although patients with TAMG experience more severe myasthenic symptoms and have worse prognoses compared to regular thymoma patients. The objective of this research is to create a transcriptome map of TAMG using genes linked to disulfidptosis, detect possible biomarkers, and examine the disparities in the tumor immune microenvironment (TIME) among different thymoma patients. The findings will offer valuable knowledge for personalized treatment alternatives.

Methods

Thymoma samples' RNA-seq data, along with their corresponding clinical data, were acquired from the TCGA database using methods. Next, genes and disulfidptosis-related lncRNAs(DRLs) were chosen through correlation analysis. Then, a prediction model of TAMG was established by LASSO regression. Subsequent to that, an analysis of the mutation data, the tumor mutational burden (TMB), and the assessment of immune and stromal elements within the tumor microenvironment were conducted.

Results

A total of 87 patients diagnosed with thymoma were included in the study, with 29 of them having TAMG. We discovered a group of 325 lncRNAs in this sample that showed significant associations with genes related to disulfidptosis, with 25 of them displaying significantly altered expression. Moreover, utilizing LASSO regression, we constructed a predictive model incorporating 11 DRLs. The analysis revealed an area under the curve (AUC) of 0.934 (CI 0.879-0.989), a cut-off value of 0.797, along with a sensitivity of 82.8 % and specificity of 93.1 %. Furthermore, we examined the TIME in both the high-risk and low-risk groups, and observed noteworthy disparities in B cells, T cells, and APC among the two groups (p < 0.05).

Conclusion

This research offers the initial examination of genes associated with disulfidptosis and TAMG through genomic and transcriptomic analysis. Furthermore, a strong risk forecasting model was created and the significance of TIME in TAMG was also clarified. The discoveries offer significant understanding into the molecular processes of TAMG and present possible indicators for categorizing risk.

Systemic Inflammatory Response Index, a Potential Inflammatory Biomarker in Disease Severity of Myasthenia Gravis: A Pilot Retrospective Study

Purpose

Myasthenia gravis (MG) is a chronic autoimmune disease caused by neuromuscular junction (NMJ) dysfunction. Our current understanding of MG's inflammatory component remains poor. The systemic inflammatory response index (SIRI) presents a promising yet unexplored biomarker for assessing MG severity. This study aimed to investigate the potential relationship between SIRI and MG disease severity.

Patients and Methods

We conducted a retrospective analysis of clinical data from 171 MG patients admitted between January 2016 and June 2021. Patients with incomplete data, other autoimmune diseases, or comorbidities were excluded. Disease severity was evaluated using the Myasthenia Gravis Foundation of America (MGFA) classification and Myasthenia Gravis Activities of Daily Living (MG-ADL) on admission. The association between SIRI and disease severity was assessed through logistic regression analysis, along with receiver operating characteristic (ROC) curve and decision curve analysis (DCA) comparisons with established inflammation indicators.

Results

After exclusion, 143 patients were analyzed in our study. SIRI levels significantly differed between patients with higher and lower disease severity (p < 0.001). Univariate logistic regression showed that SIRI had a significant effect on high disease severity (OR = 1.376, 95% CI 1.138-1.664, p = 0.001). This association remained significant even after adjusting for age, sex, disease duration, history of MG medication and thymoma (OR = 1.308, 95% CI 1.072-1.597, p = 0.008). Additionally, a positive correlation between SIRI and MG-ADL was observed (r = 0.232, p = 0.008). Significant interactions were observed between SIRI and immunosuppressor (p interaction = 0.001) and intravenous immunoglobulin (p interaction = 0.005). DCA demonstrated the superior net clinical benefit of SIRI compared to other markers when the threshold probability was around 0.2.

Conclusion

Our findings indicate a strong independent association between SIRI and disease severity in MG, suggesting SIRI's potential as a valuable biomarker for MG with superior clinical benefit to currently utilized markers.

Neurometabolic and Brain Functional Alterations Associated with Cognitive Impairment in Patients with Myasthenia Gravis: A Combined 1H-MRS and fMRI Study

Whether patients with myasthenia gravis (MG) exhibit cognitive impairment is controversial. Also the underlying mechanisms are unknown. We aimed to investigate alterations in cognitive function, neurometabolite levels, and brain function in patients with MG and to explore the associations between abnormal regional brain functional activity, neurometabolite concentrations in the MPFC and left thalamus, and cognitive activity in patients with MG. Neuropsychological tests, proton magnetic resonance spectroscopy, and resting-state functional magnetic resonance imaging were performed on 41 patients with MG and 45 race-, sex-, age-, and education-matched healthy controls (HCs). The results suggest that MG is accompanied by cognitive decline, as indicated by global cognitive function, visual-spatial function, language, memory, abnormalities in regional brain functional activity, and neurometabolite alterations (including GABA, NAA, and Cho) in the medial prefrontal cortex (MPFC) and left thalamus. Cognitive impairment in patients with MG may be related to abnormal regional brain functional activity and changes in neurometabolites, and regional brain functional activity may be modulated by specific neurometabolites.

Autoimmune and Non-Autoimmune Comorbidities in Myasthenic Patients of East-European Descent: A Case-Control Study

Background: As the life expectancy of patients with myasthenia gravis (MG) is improving, so the number of comorbidities continues to rise, with a potentially significant impact on the overall morbidity and mortality. The main aim of the study was to assess comorbidities of MG in a group of patients of East-European descent. Methods: We retrospectively compared 185 adult myasthenic patients with 895 sex- and age-matched controls, admitted from January 2013 to December 2021. Results: Of these patients, 60% had late-onset MG (LOMG), with a clear predominance of women in both the LOMG and early-onset (EOMG) types; and 23.8% of the patients had a radiological description consistent with thymoma. All myasthenic patients had at least one comorbidity; 20 (10.8%) of the patients associated at least one autoimmune comorbidity. Obesity (p < 0.01), type 2 diabetes (p < 0.0001), cerebrovascular diseases (p < 0.0001), essential hypertension (p < 0.01), and cardiac arrythmias (p < 0.0001) were more frequent in patients than in the control group. The granulocyte-to-lymphocyte ratio was higher in the myasthenic patients compared to the controls (p < 0.01 for LOMG). Discussion: We, thus, suggest a common chronic low-grade inflammatory background as a possible connection between MG subtypes and some of these apparently unconnected comorbidities. Conclusions: The East-European origin of the patients offered a different social and cultural angle of a disease studied mainly on populations of West-European and Asian descent.

Development of Upper Extremity Deep Vein Thrombosis in a Patient With Seronegative Myasthenia Gravis: A Case Report and Review of Literature

We present the case report of a patient with seronegative myasthenia gravis (MG) who was admitted for metabolic encephalopathy and acute on chronic hypoxic respiratory failure secondary to an MG crisis three days after an intravenous immunoglobulin treatment. In the intensive care unit, her MG was managed with intravenous immunoglobulin, plasmapheresis, prednisone, and pyridostigmine. During the course of her visit, she had urosepsis along with a left chest port that had cultured positive for Pseudomonas aeruginosa and developed a right upper extremity deep vein thrombosis (UEDVT) and superficial thrombosis in the left upper extremity despite being on heparin therapy. She had a transient drop in platelets to below 150,000 that resolved within a day. We analyzed the variables of this case report and reviewed the literature of similar cases to elucidate the factors that may have led to the development of the UEDVTs. The patient had many factors in her past medical history that could have contributed to her thrombosis including morbid obesity and prior history of pulmonary embolisms. It is hypothesized that MG disturbs the endothelial cell lining through an increased inflammatory state that could also be a causative factor. There is no definitive way we could link MG as a causative factor due to a lack of testing to assess alteration in the integrity or functionality of her endothelium. A case report we reviewed showed a presentation of UEDVT in an MG patient due to a thymoma compressing the subclavian vein. However, this is not the case in this example due to the patient having a history of thymectomy. She was also at risk due to her hospital stay which led to immobility and placement of a central venous catheter. We conclude the formation of the UEDVT was likely a combination of these factors.

Effects of acupuncture treatment for myasthenia gravis: A systematic review and meta-analysis

BACKGROUND

Randomized controlled trials (RCTs) of acupuncture for myasthenia gravis (MG) were searched and the efficacy of acupuncture in the treatment of MG was evaluated by meta-analysis.

METHODS

We searched for RCTs in six main electronic databases, and collected RCTs of acupuncture treatment for MG from database creation to 28 February 2023. The main outcome was the effective rate and the secondary outcome was the Traditional Chinese Medicine (TCM) relative clinical score, absolute clinical score (ACS) of MG, Quantitive myasthenia gravis score (QMG), quality of life, and adverse events. Odds ratios (ORs) and weighted mean differences (WMD) and 95% confidence intervals (CI) were used to assess pooled effect estimates using Review Manager software.

RESULTS

A total of 14 RCTs were included. Meta-analysis showed that the effective rate in the acupuncture group was significantly improved compared with conventional Western medicine alone [OR = 4.28, 95% CI (2.95, 6, 22), P<0.005]. The pooled WMDs revealed that TCM relative clinical score [WMD = -2.22, 95% CI = (-2.53, -1.90), P<0.005], ACS of MG [WMD = -3.14, 95% CI = (-3.67, -2.62), P<0.005], and QMG [WMD = -0.88, 95% CI = (-1.46, -0.29), P<0.005] in the acupuncture group was lower than the control group. Adverse reactions related to acupuncture and quality of life were less mentioned among included RCTs.

CONCLUSION

This meta-analysis demonstrated that acupuncture as an auxiliary may play a positive role in treating MG. It can improve the effective rate of treatment, and reduce TCM relative clinical score, ACS of MG, and QMG. However, the quality of included studies was generally low and caution should be exercised when considering this treatment option. In the future, more rigorous study designs and high-quality RCTs are needed to verify the efficacy of acupuncture in the treatment of MG, because the results of high-quality RCTs are more reliable and accurate.

Unlocking the Complexity of Neuromuscular Diseases: Insights from Human Pluripotent Stem Cell-Derived Neuromuscular Junctions

Over the past 20 years, the use of pluripotent stem cells to mimic the complexities of the human neuromuscular junction has received much attention. Deciphering the key mechanisms underlying the establishment and maturation of this complex synapse has been driven by the dual goals of addressing developmental questions and gaining insight into neuromuscular disorders. This review aims to summarise the evolution and sophistication of in vitro neuromuscular junction models developed from the first differentiation of human embryonic stem cells into motor neurons to recent neuromuscular organoids. We also discuss the potential offered by these models to decipher different neuromuscular diseases characterised by defects in the presynaptic compartment, the neuromuscular junction, and the postsynaptic compartment. Finally, we discuss the emerging field that considers the use of these techniques in drug screening assay and the challenges they will face in the future.