Myasthenia gravis with tongue muscle atrophy: A case series.

Here, we presented 6 patients who were admitted to our institution and diagnosed as myasthenia gravis (MG) with tongue muscle atrophy. All these 6 patients developed symptoms of bulbar muscle weakness in acetylcholine receptor antibodies positive MG (AChR-MG) (3/6), muscle-specific receptor tyrosine kinase antibodies positive MG (MuSK-MG) (1/6), and sero-negative MG (2/6). Most of patients had "triple-furrowed" tongue except for patient 2 with irregular atrophy of tongue muscle. Tongue muscle atrophy occurs in patients with MuSK-MG, AChR-MG, and sero-negative MG. Atrophied tongue muscles of five patients with MG were reversible after immunotherapy.

Batoclimab vs Placebo for Generalized Myasthenia Gravis: A Randomized Clinical Trial.

Importance: Myasthenia gravis (MG) is caused by autoantibodies that disrupt the neuromuscular junction. The neonatal fragment crystallizable receptor (FcRn) antagonists, efgartigimod and rozanolixizumab, reduce immunoglobulin G (IgG) level in the circulation and alleviate symptoms in patients with generalized MG. Objective: To examine the efficacy and safety profile of batoclimab, a monoclonal IgG1 antibody, in patients with generalized MG. Design, Setting, and Participants: This was a multicenter randomized clinical trial conducted from September 15, 2021, to June 29, 2022, at 27 centers in China. Adult patients 18 years or older with generalized MG were screened, and those who were antibody positive were enrolled. Intervention: Eligible patients received batoclimab or matching placebo in addition to standard of care. Each treatment cycle consisted of 6 weekly subcutaneous injections of batoclimab, 680 mg, or matching placebo followed by 4 weeks of observation. A second treatment cycle was conducted in patients who required continuing treatment. Main Outcome and Measure: The primary outcome was sustained improvement, as defined by a 3-point or greater reduction in the Myasthenia Gravis Activities of Daily Living (MG-ADL) score from baseline for 4 or more consecutive weeks in the first cycle in individuals who were positive for acetylcholine receptor or muscle-specific kinase antibodies. Results: A total of 178 adult patients with generalized MG were screened, 132 were randomly assigned, 131 tested positive for antibodies, and 1 tested negative for antibodies. A total of 132 patients (mean [SE] age, 43.8 [13.6] years; 88 women [67.2%]) were enrolled. The rate of sustained MG-ADL improvement in the first cycle in antibody-positive patients was 31.3% (20 of 64) in the placebo group vs 58.2% (39 of 67) in the batoclimab group (odds ratio, 3.45; 95% CI, 1.62-7.35; P = .001). The MG-ADL score diverged between the 2 groups as early as week 2. The mean (SE) maximum difference in MG-ADL score reduction occurred 1 week after the last dose (day 43, 1.7 [0.3] in the placebo group vs 3.6 [0.3] in the batoclimab group; group difference, -1.9; 95% CI, -2.8 to -1.0; nominal P < .001). The rates of treatment-related and severe treatment-emergent adverse events in patients were 36.9% (24 of 65) and 7.7% (5 of 65) in the placebo group vs 70.1% (47 of 67) and 3.0% (2 of 67) in the batoclimab group, respectively. Conclusions and Relevance: Batoclimab increased the rate of sustained MG-ADL improvement and was well tolerated in adult patients with generalized MG. Clinical effects and the extent of IgG reduction were similar to those previously reported for efgartigimod and rozanolixizumab. Future studies of large sample size are needed to further understand the safety profile of batoclimab. Trial Registration: ClinicalTrials.gov Identifier: NCT05039190.

Causal relationship between the immune phenotype of monocytes and myasthenia gravis: A Mendelian randomization study.

Background: Monocytes play an essential role in developing autoimmune diseases; however, their association with myasthenia gravis (MG) development is unclear. Methods: We performed a two-sample Mendelian randomization analysis to assess the causal relationship between monocyte-associated traits and MG, reviewing summary statistics of genome-wide association studies (GWAS). Results: Using the inverse variance weighted method, the following were found to be causally associated with MG: HLA-DR on monocytes (OR, 1.363; 95% CI, 1.158-1.605; P = 2E-04), HLA-DR on CD14+ monocytes (OR, 1.324; 95% CI, 1.183-1.482; P = 1.08E-06), HLA-DR on CD14+CD16- monocytes (OR, 1.313; 95% CI, 1.177-1.465; P = 1.07E-06), CD40 on monocytes (OR, 1.135; 95% CI, 1.012-1.272; P < 0.05), CD40 on CD14+CD16- monocytes (OR, 1.142; 95% CI, 1.015-1.285; P < 0.05), CD40 on CD14+CD16+ monocytes (OR, 1.142; 95% CI, 1.021-1.278; P < 0.05), CD64 on CD14+CD16+ monocytes (OR, 1.286; 95% CI, 1.019-1.623; P < 0.05). Conclusions: The present study suggests a causal relationship between the upregulation of CD40, HLA-DR, and CD64 on monocytes and the development of MG. Altered monocyte function may potentially be a risk factor for MG and a therapeutic target.

Altered serum levels of cytokines in patients with myasthenia gravis.

Background: Myasthenia gravis (MG) is an autoimmune disease characterized by generalized skeletal muscle contraction weakness due to autoantibodies targeting neural-muscular junctions. Here, we investigated the relationship between key cytokines and MG type, disease course, antibodies, and comorbidities. Method: Cytokine levels in serum samples collected from MG (n = 45) and healthy control (HC, n = 38) patients from January 2020 to June 2022 were quantified via flow cytometry. Results: Levels of IL-6 were higher in the MG group versus healthy individuals (p = 0.026) and in patients with generalized versus ocular MG (p = 0.019). IL-6 levels were positively correlated with QMG score. In patients with MG with both AChR and Titin antibodies, serum levels of sFas and granulysin were higher than in those with AChR alone (p = 0.036, and p = 0.028, respectively). LOMG had a reduction in serum levels of IL-2 compared to EOMG (p = 0.036). LOMG patients with diabetes had lower serum levels of IL-2, IL-4, and IFN-γ (p = 0.044, p = 0.038, and p = 0.047, respectively) versus those without diabetes. sFas in the MG with Abnormal thymus were reduced compared to those in MG with Normal thymus (p = 0.008). Conclusions: This study revealed a positive correlation between IL-6 level and MG status. Serum cytokine levels of the AChR + Titin MG group differed from those of the AChR group. LOMG had a lower IL-2 level. Comorbidities affect some cytokines in peripheral blood in MG serum.

Neuroprotective Effects of Melittin Against Cerebral Ischemia and Inflammatory Injury via Upregulation of MCPIP1 to Suppress NF-κB Activation In Vivo and In Vitro.

Melittin, a principal constituent of honeybee venom, exhibits diverse biological effects, encompassing anti-inflammatory capabilities and neuroprotective actions against an array of neurological diseases. In this study, we probed the prospective protective influence of melittin on cerebral ischemia, focusing on its anti-inflammatory activity. Mechanistically, we explored whether monocyte chemotactic protein-induced protein 1 (MCPIP1, also known as ZC3H12A), a recently identified zinc-finger protein, played a role in melittin-mediated anti-inflammation and neuroprotection. Male C57/BL6 mice were subjected to distal middle cerebral artery occlusion to create a focal cerebral cortical ischemia model, with melittin administered intraperitoneally. We evaluated motor functions, brain infarct volume, cerebral blood flow, and inflammatory marker levels within brain tissue, employing quantitative real-time polymerase chain reaction, enzyme-linked immunosorbent assays, and western blotting. In vitro, an immortalized BV-2 microglia culture was stimulated with lipopolysaccharide (LPS) to establish an inflammatory cell model. Post-melittin exposure, cell viability, and cytokine expression were examined. MCPIP1 was silenced using siRNA in LPS-induced BV-2 cells, with the ensuing nuclear translocation of nuclear factor-κB assessed through cellular immunofluorescence. In vivo, melittin enhanced motor functions, diminished infarction, fostered blood flow restoration in ischemic brain regions, and markedly inhibited the expression of inflammatory cytokines (interleukin-1ß, interleukin-6, tumor necrosis factor-α, and nuclear factor-κB). In vitro, melittin augmented MCPIP1 expression in LPS-induced BV-2 cells and ameliorated inflammation-induced cell death. The neuroprotective effect conferred by melittin was attenuated upon MCPIP1 knockdown. Our findings establish that melittin-induced tolerance to ischemic injury is intrinsically linked with its anti-inflammatory capacity. Moreover, MCPIP1 is, at the very least, partially implicated in this process.

Value evaluation of serum (sdLDLc*HCYc)/HDLc ratio in the stability of intracranial arterial plaques in patients with acute cerebral infarction.

BACKGROUND: We aimed to analyze the value of serum (sdLDLc*HCYc)/HDLc ratio in the stability of intracranial arterial plaques among patients with acute cerebral infarction. METHODS: A retrospective analysis was conducted on 140 patients with acute cerebral infarction admitted to the neurology department and 101 healthy individuals for regular examinations in our hospital from 2013 to 2019, who were respectively allocated into the study group and the control group. Participants in both groups were measured for serum sdLDLc, HDLc, and HCYc using peroxidase method, enzyme-linked immunosorbent assay, and enzyme method, respectively. The laboratory indexes of the two groups were compared. The multivariate logistic regression analysis was done to analyze the influencing factors of the stability of intracranial artery plaque in patients with acute cerebral infarction. The value of high-density lipoprotein cholesterol (HDL-C), homocysteine, sdLDLc, (sdLDLc*HCYc)/HDLc in diagnosing the stability of intracranial artery plaque was also evaluated in patients with acute cerebral infarction. RESULTS: There was no distinct difference in height, hypertension, diabetes, coronary heart disease, smoking history and drinking history between the two groups (P>0.05). The study group showed statistically significant differences in age, gender, weight, and BMI (P<0.05). The current study demonstrated no statistical difference in the levels of TG, low-density lipoprotein cholesterol (LDL-C), α-lipoprotein, and HCYc between the two groups (P>0.05). However, the levels of TC, HDL-C, sdLDLc, (sdLDLc*HCYc)/HDLc in the study group were significantly different when comparing with the control group (P<0.05). No statistically significant difference was found in the levels of TG, triglycerides, LDL-C, α-lipoprotein, and HCYc among patients with different degrees of stenosis in the study group (P>0.05). The level of HDL-C was significantly lower in cases of severe stenosis compared to no stenosis, mild stenosis and moderate stenosis, with severe stenosis showing the lowest levels; mild stenosis had lower levels than no stenosis, while moderate stenosis had lower levels than both no stenosis and mild stenosis (P<0.05). The levels of sdLDLc, (sdLDLc*HCYc)/HDLc exhibited a significant increase in cases of severe stenosis as compared tono stenosis, mild stenosis, and moderate stenosis. Furthermore, the levels of sdLDLc, (sdLDLc*HCYc)/HDLc were found to be higher in moderate stenosis as compared to no stenosis and mild stenosis. Similarly, the levels of sdLDLc, (sdLDLc*HCYc)/HDLc were observed to be higher in mild stenosis than no stenosis (P<0.05).The independent variables were set as the indicators with difference in single factor comparison, including age, gender, BMI, TC, LDL-C, HDL-C, HCYc, sdLDLc, (sdLDLc*HCYc)/HDLc. The dependent variable was the stability of intracranial artery plaque in patients with acute cerebral infarction. After variable selection, the results showed that the factors influencing the stability of intracranial artery plaque in patients with acute cerebral infarction were age, BMI, (sdLDLc*HCYc)/HDLc. The degree of plaque enhancement was used as a criterion to reflect the stability of plaque. ROC curve analysis showed that (sdLDLc*HCYc)/HDLc had a higher evaluation value for the stability of intracranial artery plaque than HDL-C, homocysteine, and sdLDLc in patients with acute cerebral infarction. CONCLUSION: The serum (sdLDLc*HCYc)/HDLc ratio was found to have potential in evaluating the stability of intracranial arterial plaques in patients with acute cerebral infarction.

U-shaped association between serum Klotho and accelerated aging among the middle-aged and elderly US population: a cross-sectional study.

BACKGROUND: Phenotypic age acceleration, which reflects the difference between phenotypic age and chronological age, is an assessment to measure accelerated aging. Klotho is a protein related to slower aging, but its association with accelerated aging remains unclear. METHODS: Based on data from the 2007-2010 National Health and Nutrition Examination Survey, phenotypic age was calculated using chronological age and 9 aging-related biomarkers. A total of 4388 participants aged 40 to 79 years with measured serum Klotho and calculated phenotypic age were enrolled. The association between serum Klotho and phenotypic age acceleration was estimated using multivariable linear regression models. The possible nonlinear relationship was examined with smooth curve fitting. We also conducted a segmented regression model to examine the threshold effect. RESULTS: The association between serum Klotho and phenotypic age acceleration followed a U-shaped curve (p for nonlinearity < 0.001), with the inflection point at 870.7 pg/ml. The phenotypic age acceleration significantly decreased with the increment of serum Klotho (per SD increment: ß -1.77; 95% CI, -2.57 ~ -0.98) in participants with serum Klotho < 870.7 pg/ml, and increased with the increment of serum Klotho (per SD increment:ß, 1.03; 95% CI: 0.53 ~ 1.54) in participants with serum Klotho ≥ 870.7 pg/ml. CONCLUSION: There was a U-shaped association between serum Klotho and accelerated aging among the middle-aged and elderly US population.

Extracellular vesicles encapsulated with caspase-1 inhibitor ameliorate experimental autoimmune myasthenia gravis through targeting macrophages.

Cysteinyl aspartate-specific proteinase-1 (caspase-1) is a multifunctional inflammatory mediator in many inflammation-related diseases. Previous studies show that caspase-1 inhibitors produce effective therapeutic outcomes in a rat model of myasthenia gravis. However, tissue toxicity and unwanted off-target effects are the major disadvantages limiting their clinical application as therapeutic agents. This study shows that dendritic cell-derived extracellular vesicles (EVs) loaded with a caspase-1 inhibitor (EVs-VX-765) are phagocytized mainly by macrophages, and caspase-1 is precisely expressed in macrophages. Furthermore, EVs-VX-765 demonstrates excellent therapeutic effects through a macrophage-dependent mechanism, and it notably inhibits the level of interleukin-1ß and subsequently inhibits Th17 response and germinal center (GC) reactions. In addition, EVs-VX-765 demonstrates better therapeutic effects than routine doses of VX-765, although drug loading is much lower than routine doses, consequently reducing tissue toxicity. In conclusion, this study's findings suggest that EV-mediated delivery of caspase-1 inhibitors is effective for treating myasthenia gravis and is promising for clinical applications.

Methylglyoxal suppresses microglia inflammatory response through NRF2-IκBζ pathway.

Methylglyoxal (MGO) is a highly reactive metabolite generated by glycolysis. Although abnormal accumulation of MGO has been reported in several autoimmune diseases such as multiple sclerosis and rheumatoid arthritis, the role of MGO in autoimmune diseases has not yet been fully investigated. In this study, we found that the intracellular MGO levels increased in activated immune cells, such as microglia and lymphocytes. Treatment with MGO inhibited inflammatory cell accumulation in the spinal cord and ameliorated the clinical symptoms in EAE mice. Further analysis indicated that MGO suppressed M1-polarization of microglia cells and diminished their inflammatory cytokine production. MGO also inhibited the ability of microglial cells to recruit and activate lymphocytes by decreasing chemokine secretion and expression of co-stimulatory molecules. Furthermore, MGO negatively regulated glycolysis by suppressing glucose transporter 1 expression. Mechanically, we found that MGO could activate nuclear factor erythroid 2-related factor 2 (NRF2) pathway and NRF2 could bind to the promoter of IκBζ gene and suppressed its transcription and subsequently pro-inflammatory cytokine production. In conclusion, our results showed that MGO acts as an immunosuppressive metabolite by activating the NRF2-IκBζ.

Epstein-Barr virus: To be a trigger of autoimmune glial fibrillary acidic protein astrocytopathy?

BACKGROUND: Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy is a novel autoimmune disease of central nervous system (CNS). It is unclear whether Epstein-Barr virus (EBV) is related to autoimmune GFAP astrocytopathy. OBJECTIVE: To describe the clinical, laboratory, and imaging characteristics of patients with autoimmune GFAP astrocytopathy. METHODS: The clinical, laboratory, and imaging findings of patients are presented. The levels of GFAP in CSF were detected by ELISA. T and B cell subsets in CSF were detected by flow cytometry. GFAP-IgG in serum and cerebrospinal fluid (CSF) were tested by cell-based assay (CBA) and tissue-based assay (TBA). RESULTS: All three patients had fever, cognitive dysfunction, limb weakness, and positive GFAP-IgG with EBV infection in CSF. Enteric glia cells may involve in this disease. Typical imaging findings include the gadolinium enhancement of linear perivascular radial perpendicular to the ventricle, meningeal enhancement (especially in midbrain interpeduncal fossa), longitudinally extensive lesions involving spindle cords, and more T2/Flair-hyperintense lesions in the periventricular white matter at late stage. The patients had poor response to antiviral treatment and strong response to steroid pulse therapy. CONCLUSION: EBV could induce CNS autoimmune response in autoimmune GFAP astrocytopathy. The detection of GFAP-IgG and EBV may facilitate the early diagnosis in these patients.

Association and mediating mechanism between remnant cholesterol and first-ever stroke among the Chinese general population.

Background: Remnant cholesterol (RC) has been suggested to be implicated in atherosclerosis. The objective of the study was to evaluate the association between RC and first-ever stroke in the Chinese general population and to investigate whether the association is mediated via hypertension or diabetes. Methods: This study is a retrospective cohort analysis of participants from the China Health and Nutrition Survey. Participants without previous stroke and myocardial infarction in 2009 were enrolled and followed up in 2011 and 2015. Logistic regression analyses were adopted to explore the association of RC with stroke risk. Propensity score methods and doubly robust estimation method were used to ensure the robustness of our findings. Potential mediators were identified by mediation analyses. Results: A total of 7,035 participants were involved, and during 6 years of follow-up, 78 (1.1%) participants experienced a first-ever stroke. Participants with high RC had a significantly higher incidence of stroke (1.4% versus 0.8%; p = 0.007). High RC was associated with 74% higher stroke risk after adjusting for multiple relevant variables (odds ratio [OR], 1.74; 95% CI, 1.06-2.85). The association was consistent in analyses using propensity score methods and doubly robust estimation method. Hypertension showed a significant mediating effect on the association between RC and stroke, while the mediating effect of diabetes was not significant. Conclusion: High RC increased the risk of first-ever stroke in the Chinese general population without previous stroke and myocardial infarction, partially through the pathway of hypertension. RC might be a potential target for the primary prevention of stroke.

Type 2 diabetes mellitus as a possible risk factor for myasthenia gravis: a case-control study.

Background: A certain number of myasthenia gravis (MG) patients clinically had type 2 diabetes mellitus (T2DM) prior to MG onset, which suggests that the onset of MG may correlate with the history of T2DM. This study aimed to examine the correlation between MG and T2DM. Methods: In a single-center, retrospective, 1:5 matched case-control study, all 118 hospitalized patients with a diagnosis of MG from 8 August 2014 to 22 January 2019 were enrolled. In total, four datasets with different sources of the control group were retrieved from the electronic medical records (EMRs). Data were collected at the individual level. A conditional logistic regression analysis was used to test the risk of MG associated with T2DM. Findings: The risk of MG was significantly associated with T2DM, and there were notable differences by sex and age. Whether compared to the general population, general hospitalized patients without autoimmune diseases (AIDs), or patients with other AIDs except MG, women aged over 50 years with T2DM had an increased risk of MG. The mean onset age of diabetic MG patients was more than that of the non-diabetic MG patients. Interpretation: This study demonstrates that T2DM is strongly associated with the subsequent risk of MG and varies significantly by sex and age. It reveals that diabetic MG may be a unique subtype that is different from the conventional MG subgroup classification. More clinical and immunological features of diabetic MG patients need to be explored in further studies.

Circulating CXCR5+ natural killer cells are expanded in patients with myasthenia gravis.

Objectives: Myasthenia gravis (MG) is a classic autoantibody-mediated disease in which pathogenic antibodies target postsynaptic membrane components, causing fluctuating skeletal muscle weakness and fatigue. Natural killer (NK) cells are heterogeneous lymphocytes that have gained increasing attention owing to their potential roles in autoimmune disorders. This study will investigate the relationship between the distinct NK cell subsets and MG pathogenesis. Methods: A total of 33 MG patients and 19 healthy controls were enrolled in the present study. Circulating NK cells, their subtypes and follicular helper T cells were analysed by flow cytometry. Serum acetylcholine receptor (AChR) antibody levels were determined by ELISA. The role of NK cells in the regulation of B cells was verified using a co-culture assay. Results: Myasthenia gravis patients with acute exacerbations had a reduced number of total NK cells, CD56dim NK cells and IFN-γ-secreting NK cells in the peripheral blood, while CXCR5+ NK cells were significantly elevated. CXCR5+ NK cells expressed a higher level of ICOS and PD-1 and a lower level of IFN-γ than those in CXCR5- NK cells and were positively correlated with Tfh cell and AChR antibody levels. In vitro experiments demonstrated that NK cells suppressed plasmablast differentiation while promoting CD80 and PD-L1 expression on B cells in an IFN-γ-dependent manner. Furthermore, CXCR5- NK cells inhibited plasmablast differentiation, while CXCR5+ NK cells could more efficiently promote B cell proliferation. Conclusion: These results reveal that CXCR5+ NK cells exhibit distinct phenotypes and functions compared with CXCR5- NK cells and might participate in the pathogenesis of MG.

Short-term outcome prediction for myasthenia gravis: an explainable machine learning model.

Background: Myasthenia gravis (MG) is an autoimmune disease characterized by muscle weakness and fatigability. The fluctuating nature of the disease course impedes the clinical management. Objective: The purpose of the study was to establish and validate a machine learning (ML)-based model for predicting the short-term clinical outcome in MG patients with different antibody types. Methods: We studied 890 MG patients who had regular follow-ups at 11 tertiary centers in China from 1 January 2015 to 31 July 2021 (653 patients for derivation and 237 for validation). The short-term outcome was the modified post-intervention status (PIS) at a 6-month visit. A two-step variable screening was used to determine the factors for model construction and 14 ML algorithms were used for model optimisation. Results: The derivation cohort included 653 patients from Huashan hospital [age 44.24 (17.22) years, female 57.6%, generalized MG 73.5%], and the validation cohort included 237 patients from 10 independent centers [age 44.24 (17.22) years, female 55.0%, generalized MG 81.2%]. The ML model identified patients who were improved with an area under the receiver operating characteristic curve (AUC) of 0.91 [0.89-0.93], 'Unchanged' 0.89 [0.87-0.91], and 'Worse' 0.89 [0.85-0.92] in the derivation cohort, whereas identified patients who were improved with an AUC of 0.84 [0.79-0.89], 'Unchanged' 0.74 [0.67-0.82], and 'Worse' 0.79 [0.70-0.88] in the validation cohort. Both datasets presented a good calibration ability by fitting the expectation slopes. The model is finally explained by 25 simple predictors and transferred to a feasible web tool for an initial assessment. Conclusion: The explainable, ML-based predictive model can aid in forecasting the short-term outcome for MG with good accuracy in clinical practice.

Diabetes mellitus aggravates humoral immune response in myasthenia gravis by promoting differentiation and activation of circulating Tfh cells.

Myasthenia gravis (MG) is a T-cell-dependent, antibody-mediated autoimmune disease. Diabetes mellitus (DM) is a chronic metabolic disease characterized by hyperglycemia and emerging evidence indicates its profound impacts on the immune homeostasis. Previous studies and our data showed DM might serve as an independent risk factor of MG, yet the underlying immune and molecular mechanisms remain to be addressed. Our study observed that circulating Tfh (cTfh) cells were increased in MG patients with DM and expressed a high level of ICOS. Besides, positive correlations between activated cTfh cells and plasmablasts were documented. Further studies demonstrated hyperglycemia promoted the differentiation and activation of Tfh cells which, in turn, caused abnormal plasmablasts differentiation and antibody secretion through the mTOR signaling pathway. These results indicated DM might aggravate the aberrant humoral immunity in MG patients by augmenting Tfh cells differentiation and function and tight glycemic control might be beneficial for MG patients with DM.

Therapeutic Effects of Batoclimab in Chinese Patients with Generalized Myasthenia Gravis: A Double-Blinded, Randomized, Placebo-Controlled Phase II Study.

INTRODUCTION: We investigated the safety and explore potential efficacy of batoclimab administered subcutaneously in Chinese patients with generalized myasthenia gravis (gMG). METHODS: A randomized, double-blinded, placebo-controlled, parallel phase II study was conducted. First, in the double-blinded treatment period, eligible patients received batoclimab (680 mg), batoclimab (340 mg), or placebo on days 1, 8, 15, 22, 29, and 36. In the open-label treatment period, patients received batoclimab (340 mg) on days 50, 64, and 78. In the follow-up period, patients were examined on days 92, 106, and 120. The primary endpoint was Myasthenia Gravis Activities of Daily Living (MG-ADL) score change on day 43 from baseline. RESULTS: In total, 30 eligible patients were enrolled, with 11, 10, and 9 patients in the batoclimab 680 mg, batoclimab 340 mg, and placebo groups, respectively. MG-ADL score changes from baseline to day 43 were -2.2 ± 0.9, -4.7 ± 0.6, and -4.4 ± 1.0 in the placebo, batoclimab 340 mg, and 680 mg groups, respectively. Similar changes were observed in Quantitative Myasthenia Gravis, Myasthenia Gravis Composite, and 15-item Myasthenia Gravis Quality of Life scores in the placebo, batoclimab 340 mg, and 680 mg groups, respectively. The proportion of patients with clinically significant improvement on day 43 was higher in the batoclimab groups. On day 120, all four scales in the placebo group had more significant improvement compared with the batoclimab groups, with total serum IgG levels reaching a plateau. No death or treatment-emergent adverse events (TEAEs) led to study discontinuation. CONCLUSION: Batoclimab is effective and safe in Chinese patients with gMG. TRIAL REGISTRATION: This study was registered at ClinicalTrials.gov (NCT04346888) on 15 April 2020, with the first patient enrolled on 23 July 2020.

Diabetes mellitus exacerbates experimental autoimmune myasthenia gravis via modulating both adaptive and innate immunity.

BACKGROUND: Diabetes mellitus (DM) is a common concomitant disease of late-onset myasthenia gravis (MG). However, the impacts of DM on the progression of late-onset MG were unclear. METHODS: In this study, we examined the immune response in experimental autoimmune myasthenia gravis (EAMG) rats with DM or not. The phenotype and function of the spleen and lymph nodes were determined by flow cytometry. The serum antibodies, Tfh cells, and germinal center B cells were determined by ELISA and flow cytometry. The roles of advanced glycation end products (AGEs) in regulating Tfh cells were further explored in vitro by co-culture assays. RESULTS: Our results indicated clinical scores of EAMG rats were worse in diabetes rats compared to control, which was due to the increased production of anti-R97-116 antibody and antibody-secreting cells. Furthermore, diabetes induced a significant upregulation of Tfh cells and the subtypes of Tfh1 and Tfh17 cells to provide assistance for antibody production. The total percentages of B cells were increased with an activated statue of improved expression of costimulatory molecules CD80 and CD86. We found CD4+ T-cell differentiation was shifted from Treg cells towards Th1/Th17 in the DM+EAMG group compared to the EAMG group. In addition, in innate immunity, diabetic EAMG rats displayed more CXCR5 expression on NK cells. However, the expression of CXCR5 on NKT cells was down-regulated with the increased percentages of NKT cells in the DM+EAMG group. Ex vivo studies further indicated that Tfh cells were upregulated by AGEs instead of hyperglycemia. The upregulation was mediated by the existence of B cells, the mechanism of which might be attributed the elevated molecule CD40 on B cells. CONCLUSIONS: Diabetes promoted both adaptive and innate immunity and exacerbated clinical symptoms in EAMG rats. Considering the effect of diabetes, therapy in reducing blood glucose levels in MG patients might improve clinical efficacy through suppressing the both innate and adaptive immune responses. Additional studies are needed to confirm the effect of glucose or AGEs reduction to seek treatment for MG.