IL-4Rα Polymorphism Is Associated With Myasthenia Gravis in Chinese Han Population

Identification and validation of lncRNA mutation hotspot SNPs associated with myasthenia gravis susceptibility

Background

Myasthenia gravis (MG) is an autoimmune disorder caused by antibodies that target the postsynaptic muscle membrane. Recent evidence suggests that genetic variants and long noncoding RNAs (lncRNAs) play crucial roles in the pathogenesis of MG. The purpose of this study was to investigate the associations between lncRNA-related single-nucleotide polymorphisms (SNPs) and MG susceptibility in Chinese populations.

Methods

First, we identified lncRNA mutation hotspot regions based on the improved Kolmogorov‒Smirnov test and the cumulative hypergeometric distribution principle. Next, we further identified lncRNA mutation hotspot SNPs by calculating conservative scores. Finally, experiments were conducted to verify the associations between lncRNA mutation hotspot SNPs and MG susceptibility. A total of 82 patients with MG and 82 healthy controls were recruited for genotyping of lncRNA mutation hotspot SNPs using the SNaPshot technique. Quantitative real-time PCR was used to investigate lncRNA expression in 34 patients with MG and 37 healthy controls.

Results

In the multistep calculation, 14 candidate SNPs of 3 lncRNAs (AL031686.1, NONHSAT028539.2 and AC245014.3) in MG were identified as mutation hotspot SNPs. The genotyping results of the 14 SNPs in our study revealed no statistically significant differences in the frequencies of genotypes and alleles between patients with MG and controls. However, in the lncRNA AL031686.1, rs1000383 and rs6094353 were in perfect linkage disequilibrium (LD) and were associated with an increased risk of ocular MG. Additionally, rs6094347 was associated with an increased risk of ocular MG. Nevertheless, no SNP was found to be associated with factors such as sex, age, the presence or absence of thymoma, or the genetic model of MG. Further experiments revealed that NONHSAT028539.2 expression was upregulated in peripheral blood mononuclear cells (PBMCs) from patients with MG compared with those from healthy controls.

Conclusion

In our study, we did not find an association between the 14 mutation hotspot SNPs of lncRNAs and susceptibility to MG. However, we observed that the rs6094347 and rs1000383/rs6094353 polymorphisms in the lncRNA AL031686.1 were associated with the risk of ocular MG.

IL-4Rα (rs1801275) A>G polymorphism in Egyptian immune thrombocytopenia (ITP) patients: a single center experience

INTRODUCTION

Chronic immune thrombocytopenia (cITP) is characterized by dysregulation of the immune response. Until recently, the role of Th2-related cytokine gene polymorphisms was unclear. Interleukin 4 (IL-4) exerts its functions by binding to three types of IL-4 receptor (IL-4R) complexes. We aimed to explore the potential association between the gene polymorphism of IL-4Rα and cITP.

METHODS

We investigated the clinical impact of the IL-4Rα (rs1801275) A>G single nucleotide polymorphism (SNP) using the polymerase chain reaction (PCR) followed by the restriction fragment length polymorphism (RFLP) method in 82 cITP patients and 60 healthy controls (HCs).

RESULTS

The IL-4Rα (rs1801275) A>G polymorphism analysis showed the mutant GG genotype was significantly higher in control females (p = 0.033). The wild AA genotype had a higher bleeding score (p = 0.02) in the adulthood onset group. Furthermore, the wild AA genotype in the cITP childhood onset group was significantly associated with the disease severity, as well as the response to treatment (p = 0.040).

CONCLUSION

The mutant G allele is protective against the susceptibility to cITP in the Egyptian females. The IL-4Rα (rs1801275) A>G polymorphism may affect the clinical severity of cITP and treatment response in the Egyptian population.

Vitamin D receptor gene polymorphisms are associated with the risk and features of myasthenia gravis in the Han Chinese population

Vitamin D receptor gene (VDR) polymorphisms are candidate genetic variants for susceptibility to autoimmune diseases. Here, we explored the association between VDR polymorphisms and myasthenia gravis (MG) susceptibility and disease features in a Han Chinese population. A total of 151 patients with MG and 146 healthy controls were genotyped for VDR rs1544410, rs2228570, rs731236, and rs7975232 polymorphisms using the improved multiple ligase detection reaction. Information regarding age at onset, acetylcholine receptor (AChR-Ab) and muscle-specific kinase (MuSK-Ab) antibody status, thymus status, involved muscles at onset, and Osserman type at maximum worsening during 2-year follow-up was obtained and used for subclassification grouping. Intergroup comparisons of allele and genotype frequencies and haplotype distributions were performed between the MG and control groups and between each pair of MG subgroups. The VDR rs7975232 polymorphism was associated with the risk of MG in allele, codominant (CC vs. CA), and dominant models (p = 0.040, p = 0.018, and p = 0.018, respectively). Moreover, subjects with the ACC haplotype (order of rs731236, rs7975232, rs1544410) were more likely to develop MG than those with other haplotypes (OR = 1.486, 95% CI: 1.017-2.171, p = 0.040). In a dominant model, the rs7975232 CC genotype frequency was significantly higher in the ocular MG group than in the generalized MG group (p = 0.019). The study findings suggest that the VDR rs7975232 C allele and the ACC haplotype can be associated to an increased susceptibility to the development of MG. Trial registration: NCT05380128.

What Is Different in Acute Hematologic Malignancy-Associated ARDS? An Overview of the Literature

Background and Objectives: Acute hematologic malignancies are a group of heterogeneous blood diseases with a high mortality rate, mostly due to acute respiratory failure (ARF). Acute respiratory distress syndrome (ARDS) is one form of ARF which represents a challenging clinical condition. The paper aims to review current knowledge regarding the variable pathogenic mechanisms, as well as therapeutic options for ARDS in acute hematologic malignancy patients. Data collection: We provide an overview of ARDS in patients with acute hematologic malignancy, from an etiologic perspective. We searched databases such as PubMed or Google Scholar, including articles published until June 2022, using the following keywords: ARDS in hematologic malignancy, pneumonia in hematologic malignancy, drug-induced ARDS, leukostasis, pulmonary leukemic infiltration, pulmonary lysis syndrome, engraftment syndrome, diffuse alveolar hemorrhage, TRALI in hematologic malignancy, hematopoietic stem cell transplant ARDS, radiation pneumonitis. We included relevant research articles, case reports, and reviews published in the last 18 years. Results: The main causes of ARDS in acute hematologic malignancy are: pneumonia-associated ARDS, leukostasis, leukemic infiltration of the lung, pulmonary lysis syndrome, drug-induced ARDS, radiotherapy-induced ARDS, diffuse alveolar hemorrhage, peri-engraftment respiratory distress syndrome, hematopoietic stem cell transplantation-related ARDS, transfusion-related acute lung injury. Conclusions: The short-term prognosis of ARDS in acute hematologic malignancy relies on prompt diagnosis and treatment. Due to its etiological heterogeneity, precision-based strategies should be used to improve overall survival. Future studies should focus on identifying the relevance of such etiologic-based diagnostic strategies in ARDS secondary to acute hematologic malignancy.

Vitamin D Receptor Polymorphism and Myasthenia Gravis in Chinese Han Population

Myasthenia gravis (MG) is an autoimmune disease in which antibodies bind to acetylcholine receptors (AChR) or other functional molecules in the postsynaptic membrane at the neuromuscular junction. Vitamin D (VD) has a number of pluripotent effects, which include immune-regulation and bone metabolism. The immunomodulatory actions of 1,25(OH)2D3 are mediated by its binding to a vitamin D receptor (VDR). In the study, we undertook a case-control study to explore the association between VDR gene polymorphism and the susceptibility and severity of MG patients. Four hundred and eighty MG patients and 487 healthy controls were included and gene polymorphisms of VDR were determined with improved multiplex ligation detection reaction technique and SNPscan^TM technique. MG patients were classified into subgroups by essential clinical features and by a comprehensive classification. The frequencies of alleles and genotypes were compared between the MG group and the control group, between each MG subgroup and the control group, and between each pair of MG subgroups. There were no significant differences in frequencies of alleles and genotypes between MG patients and healthy controls, between MG subgroups and healthy controls, or between each pair of MG subgroups in the analysis of subgroups classified by essential clinical features (onset age, gender, thymoma, AChRAb positivity, onset involvement) and the maximal severity (modified Oosterhuis score). In the analysis of subgroups with a comprehensive classification, the frequencies of alleles and genotypes in rs731236 showed significant differences between adult non-thymoma AChRAb negative MG subgroup and the control group, as well as the adult non-thymoma AChRAb positive MG group. In the Chinese Han population, rs731236 was found to be possibly associated with adult non-thymoma AChRAb negative MG patients, although this needs further confirmation.

Associations of BAFF rs2893321 polymorphisms with myasthenia gravis susceptibility

Background

Myasthenia gravis (MG) is an autoimmune diseases characterized by fatigue and weakness of skeletal muscles. B-lymphocyte-activating factor (BAFF), an essential factor for B cell differentiation and development, is important in the progression of MG. The current study aimed to investigate the association between single nucleotide polymorphism rs2893321 in BAFF with MG susceptibility in Chinese Han population.

Methods

One hundred forty-nine patients with MG and 148 healthy controls were recruited. Using improved multiple ligase detection reaction technology, the polymorphisms of rs2893321 between groups and among MG subgroups have been compared.

Results

A significant differences between the MG group and the healthy control group was observed. Additionally, rs2893321 was found to be associated with gender and age in patients with MG.

Conclusion

Genetic variations of rs2893321 in BAFF might be associated with susceptibility to MG in the Chinese Han population.

Identifying the culprits in neurological autoimmune diseases

The target organ of neurological autoimmune diseases (NADs) is the central or peripheral nervous system. Multiple sclerosis (MS) is the most common NAD, whereas Guillain-Barré syndrome (GBS), myasthenia gravis (MG), and neuromyelitis optica (NMO) are less common NADs, but the incidence of these diseases has increased exponentially in the last few years. The identification of a specific culprit in NADs is challenging since a myriad of triggering factors interplay with each other to cause an autoimmune response. Among the factors that have been associated with NADs are genetic susceptibility, epigenetic mechanisms, and environmental factors such as infection, microbiota, vitamins, etc. This review focuses on the most studied culprits as well as the mechanisms used by these to trigger NADs.

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Neurological autoimmune diseases are caused by a complex interaction between genes, environmental factors, and epigenetic deregulation.

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Infectious agents can cause an autoimmune reaction to myelin epitopes through molecular mimicry and/or bystander activation.

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Gut microbiota dysbiosis contributes to neurological autoimmune diseases.

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Smoking increases the risk of NADs through inflammatory signaling pathways, oxidative stress, and Th17 differentiation.

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Deficiency in vitamin D favors NAD development through direct damage to the central and peripheral nervous system.