BLK and BANK1 polymorphisms and interactions are associated in Mexican patients with systemic lupus erythematosus

Interactions between TNFAIP3, PTPN22, and TRAF1-C5 gene polymorphisms in patients with primary Sjögren's syndrome

Objectives

The aim of our study was to investigate whether TNFAIP3, PTPN22, and TRAF1-5 single nucleotide polymorphisms (SNPs) are associated with susceptibility, severity, or serological markers in primary Sjögren's syndrome (pSS).

Patients and methods

The cases and controls study was conducted between December 2021 and June 2022. TNFAIP3 rs10499194C/T, rs6920220G/A, and rs2230926T/G, PTPN22 rs2476601C/T and rs33996649G/A, and TRAF1-C5 rs10818488G/A polymorphisms were genotyped in 154 female pSS patients (mean age: 45.2±6.8 years) and 313 female control subjects (mean age: 50.3±7.5 years) using the TaqMan® SNP genotyping assay. An association analysis between TNFAIP3, PTPN22, and TRAF1-C5 SNPs and susceptibility, clinical characteristics, and serological markers of pSS was performed. Interactions between TNFAIP3, PTPN22, and TRAF1-C5 SNPs were also evaluated in patients and controls.

Results

The genotype and allele frequencies showed no association with susceptibility, severity, or serological markers of pSS. Nevertheless, several interactions between TNFAIP3 and TRAF1-C5 or TNFAIP3, PTPN22, and TRAF1-C5 genotypes were associated with susceptibility to pSS (p<0.01).

Conclusion

Individual TNFAIP3, PTPN22, and TRAF1-C5 SNPs are not associated with susceptibility, severity, or serological markers of pSS. However, genetic interactions between TRAF1-C5 and TNFAIP3 or TNFAIP3, PTPN22, and TRAF1-C5 SNPs are risk factors for pSS.

Dynamic Changes of an Anodized FeNi Alloy during the Oxygen Evolution Reaction under Alkaline Conditions

An efficient and durable oxygen evolution reaction (OER) catalyst is necessary for the water-splitting process toward energy conversion. The OER through water oxidation reactions could provide electrons for H2O, CO2, and N2 reduction and produce valuable compounds. Herein, the FeNi (1:1 Ni/Fe) alloy as foam, after anodizing at 50 V in a two-electrode system in KOH solution (1.0 M), was characterized by Raman spectroscopy, diffuse reflectance spectroscopy (DRS), X-ray absorption spectroscopy (XAS), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDX), transmission electron microscopy (TEM), high-angle annular dark-field imaging (HAADF)-scanning transmission electron microscopy (STEM) and used as an efficient and durable OER electrocatalyst in KOH solution (1.0 M). The overpotential for the onset of the OER based on extrapolation of the Tafel plot was 225 mV. The overpotentials for the current densities of 10 and 30 mA/cm2 are observed at 270 and 290 mV, respectively. In addition, a low Tafel slope is observed, 38.0 mV per decade, for the OER. To investigate the mechanism of the OER, in situ surface-enhanced Raman spectroscopy was used to detect FeNi hydroxide and characteristic peaks of H2O. Impurities in KOH can adsorb onto the electrode surface during the OER. Peaks corresponding to Ni(III) (hydr)oxide and FeO42- can be detected during the OER, but high-valent FeNi (hydr)oxides are unstable and reduce under the open circle potential. Metal hydroxide transformations during the OER and anion adsorption should be carefully considered. In addition, Fe3O4 may convert to γ-Fe2O3 during the OER. This study aims to offer logical perspectives on the dynamic changes that occur during the OER under alkaline conditions in an anodized FeNi alloy. These changes encompass variations in morphology, surface oxidation, the generation of high-valent species, and phase conversion during the OER.

Weighted gene co-expression network analysis identifies dysregulated B-cell receptor signaling pathway and novel genes in pulmonary arterial hypertension

Background

Pulmonary arterial hypertension (PAH) is a devastating cardio-pulmonary vascular disease in which chronic elevated pulmonary arterial pressure and pulmonary vascular remodeling lead to right ventricular failure and premature death. However, the exact molecular mechanism causing PAH remains unclear.

Methods

RNA sequencing was used to analyze the transcriptional profiling of controls and rats treated with monocrotaline (MCT) for 1, 2, 3, and 4 weeks. Weighted gene co-expression network analysis (WGCNA) was employed to identify the key modules associated with the severity of PAH. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed to explore the potential biological processes and pathways of key modules. Real-time PCR and western blot analysis were used to validate the gene expression. The hub genes were validated by an independent dataset obtained from the Gene Expression Omnibus database.

Results

A total of 26 gene modules were identified by WGCNA. Of these modules, two modules showed the highest correlation with the severity of PAH and were recognized as the key modules. GO analysis of key modules showed the dysregulated inflammation and immunity, particularly B-cell-mediated humoral immunity in MCT-induced PAH. KEGG pathway analysis showed the significant enrichment of the B-cell receptor signaling pathway in the key modules. Pathview analysis revealed the dysregulation of the B-cell receptor signaling pathway in detail. Moreover, a series of humoral immune response-associated genes, such as BTK, BAFFR, and TNFSF4, were found to be differentially expressed in PAH. Additionally, five genes, including BANK1, FOXF1, TLE1, CLEC4A1, and CLEC4A3, were identified and validated as the hub genes.

Conclusion

This study identified the dysregulated B-cell receptor signaling pathway, as well as novel genes associated with humoral immune response in MCT-induced PAH, thereby providing a novel insight into the molecular mechanisms underlying inflammation and immunity and therapeutic targets for PAH.

TNFSF4 is a risk factor for rheumatoid arthritis but not for primary Sjögren's syndrome in the Mexican population

PURPOSE

Rheumatoid arthritis (RA) and primary Sjögren's syndrome (pSS) are autoimmune diseases (ADs) characterized by joint damage and involvement of the salivary glands, respectively. ADs share some susceptibility loci, such as TNFSF4, which is a classical susceptibility gene associated with systemic lupus erythematosus, but its role in RA and pSS is not yet clear. Thus, the aim of this study was to determine whether three TNFSFS4 polymorphisms are associated with RA and pSS.

METHODS

Our case-control study included 500 controls, 459 patients with RA, and 210 patients with pSS from Mexico. TNFSF4 single nucleotide polymorphisms (SNPs) rs1234315C/T, rs2205960G/T, and rs704840T/G were genotyped using TaqMan probes and discrimination allelic assay.

RESULTS

The three TNFSF4 SNPs were associated with susceptibility to RA (rs1234315C/T: odds ratio [OR] 1.4, p = 0.01; rs2205960G/T: OR 1.23, p = 0.03; rs704840T/G: OR 1.24, p = 0.02). An association between TNFSF4 rs1234315C/T and pSS was also observed (OR 1.28, p = 0.04), however, after Bonferroni correction, this association was lost.

CONCLUSION

Our data suggest that TNFSF4 could be a risk factor in RA but not pSS in a Mexican population.

Variants in BANK1 are associated with lupus nephritis of European ancestry

The genetic background of lupus nephritis (LN) has not been completely elucidated. We performed a case-only study of 2886 SLE patients, including 947 (33%) with LN. Renal biopsies were available from 396 patients. The discovery cohort (Sweden, n = 1091) and replication cohort 1 (US, n = 962) were genotyped on the Immunochip and replication cohort 2 (Denmark/Norway, n = 833) on a custom array. Patients with LN, proliferative nephritis, or LN with end-stage renal disease were compared with SLE without nephritis. Six loci were associated with LN (p < 1 × 10⁻⁴, NFKBIA, CACNA1S, ITGA1, BANK1, OR2Y, and ACER3) in the discovery cohort. Variants in BANK1 showed the strongest association with LN in replication cohort 1 (p = 9.5 × 10⁻⁴) and proliferative nephritis in a meta-analysis of discovery and replication cohort 1. There was a weak association between BANK1 and LN in replication cohort 2 (p = 0.052), and in the meta-analysis of all three cohorts the association was strengthened (p = 2.2 × 10⁻⁷). DNA methylation data in 180 LN patients demonstrated methylation quantitative trait loci (meQTL) effects between a CpG site and BANK1 variants. To conclude, we describe genetic variations in BANK1 associated with LN and evidence for genetic regulation of DNA methylation within the BANK1 locus. This indicates a role for BANK1 in LN pathogenesis.

The Role of BANK1 in B Cell Signaling and Disease

The B cell scaffold protein with ankyrin repeats (BANK1) is expressed primarily in B cells and with multiple but discrete roles in B cell signaling, including B cell receptor signaling, CD40-related signaling, and Toll-like receptor (TLR) signaling. The gene for BANK1, located in chromosome 4, has been found to contain genetic variants that are associated with several autoimmune diseases and also other complex phenotypes, in particular, with systemic lupus erythematosus. Common genetic variants are associated with changes in BANK1 expression in B cells, while rare variants modify their capacity to bind efferent effectors during signaling. A BANK1-deficient model has shown the importance of BANK1 during TLR7 and TLR9 signaling and has confirmed its role in the disease. Still, much needs to be done to fully understand the function of BANK1, but the main conclusion is that it may be the link between different signaling functions within the B cells and they may act to synergize the various pathways within a cell. With this review, we hope to enhance the interest in this molecule.

Polymorphisms in TNFAIP3, but not in STAT4, BANK1, BLK, and TNFSF4, are associated with susceptibility to Takayasu arteritis

BACKGROUND

Takayasu arteritis (TAK) is considered a rare disease characterized by nonspecific inflammation of the large arteries, especially the aorta and its major branches. Because TAK is an autoimmune disease (AD), it could share susceptibility loci with other pathologies such as systemic lupus erythematosus (SLE), and rheumatoid arthritis (RA), among others. Widely explored polymorphisms in non-HLA genes, including TNFAIP3, STAT4, TNFSF4, BANK1, and BLK have been consistently associated with both SLE and RA, but they have not been evaluated in TAK.

OBJECTIVE

The aim of our study was to investigate whether TNFAIP3, STAT4, BANK1, BLK, and TNFSF4 polymorphisms are associated with susceptibility to TAK.

METHODS

The TNFAIP3 rs2230926T/G and rs5029924C/T, STAT4 rs7574865G/T, BANK1 10516487G/A, BLK rs2736340T/C, rs13277113A/G, and TNFS4 rs2205960G/T polymorphisms were genotyped in 101 cases and 276 controls by using a TaqMan SNP genotyping assay. An association analysis was performed.

RESULTS

The TNFAIP3 rs2230926T/G and rs5029924C/T polymorphisms were in complete linkage disequilibrium and turned out to be risk factors for TAK (OR = 4.88, p = 0.0001). The STAT4, BANK1, BLK, and TNFSF4 polymorphisms were not associated with the disease.

CONCLUSIONS

This is the first study documenting an association of TNFAIP3 rs2230926T/G and rs5029924C/T with TAK. Our results provide new information on the genetic bases of TAK.

TLR4 and TLR9 polymorphisms are not associated with either rheumatoid arthritis or systemic lupus erythematosus in Mexican patients

Toll-like receptor (TLR)-mediated signaling pathways induce a proinflammatory microenvironment to eradicate pathogens. However, in rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), TLRs can promote chronic inflammation. It has been shown that some TLR4 and TLR9 single nucleotide polymorphisms (SNPs) are risk factors for RA and SLE, but these findings have not been replicated in all populations; thus, results are inconclusive. We evaluated the TLR4 Asp299Gly, Thr399Ile, - 1892G/A SNPs, and the TLR9 Pro545Pro SNP to assess potential associations with RA and SLE in Mexican patients. This study included 474 patients with RA, 283 patients with SLE, and 424 healthy controls. We used a 5' nuclease allelic discrimination assay to genotype individuals for the four TLR4 and TLR9 polymorphisms. We found that the genotype or allelic frequencies of the TLR4 Asp299Gly, Thr399Ile, - 1892G/A, and TLR9 Pro545Pro polymorphisms were similar between patients and controls. We found no association under different genetic models. A haplotype analysis of TLR4 showed no association with either RA or SLE. We found no significant differences in the allelic or genotypic frequencies of TLR4 Asp299Gly, Thr399IIe, - 1892G/A, or TLR9 Pro545Pro between patients and controls. These findings suggested that these variants are not risk factors for RA or SLE in Mexican patients.

BLK and BANK1 variants and interactions are associated with susceptibility for primary Sjögren's syndrome and with some clinical features

BLK and BANK1 in primary Sjögren's syndrome (pSS) have scarcely been evaluated and the results are inconclusive. The aim of our study was to determine whether single nucleotide variants (SNVs) located within BLK or BANK1 are associated with susceptibility, clinical and serological features, and smoking in pSS. BLK rs13277113A/G, BANK1 rs10516487G/A and rs3733197G/A were genotyped in 203 cases and 424 controls using a TaqMan® SNP genotyping assay. The BLK rs13277113A allele showed association with pSS under the allelic (OR 1.35, p = 0.02), and recessive (OR 1.83, p = 0.003) model, while, BANK1 rs3733197G/A showed association under the dominant model (OR 2.90, p = 0.043). Interactions between BANK1 and BLK genotypes also showed association (OR 2.36, p < 0.0001). In addition, BLK rs13277113A/G was associated with protection against arthritis and BANK1 rs10516487G/A with both arthritis and keratoconjunctivitis sicca, meanwhile, BANK1 rs3733197G/A was associated with smoking in patients with pSS. This is the first study to describe an association between BLK and susceptibility to pSS in a Latin-American population. Our data also shows a first evidence of association between interactions of BLK and BANK1 in pSS, and association of BLK and BANK1with arthritis, keratoconjunctivitis sicca and smoking in patients with pSS.

Meta-analysis of genome-wide association study identifies FBN2 as a novel locus associated with systemic lupus erythematosus in Thai population

BACKGROUND

Differences in the expression of variants across ethnic groups in the systemic lupus erythematosus (SLE) patients have been well documented. However, the genetic architecture in the Thai population has not been thoroughly examined. In this study, we carried out genome-wide association study (GWAS) in the Thai population.

METHODS

Two GWAS cohorts were independently collected and genotyped: discovery dataset (487 SLE cases and 1606 healthy controls) and replication dataset (405 SLE cases and 1590 unrelated disease controls). Data were imputed to the density of the 1000 Genomes Project Phase 3. Association studies were performed based on different genetic models, and pathway enrichment analysis was further examined. In addition, the performance of disease risk estimation for individuals in Thai GWAS was assessed based on the polygenic risk score (PRS) model trained by other Asian populations.

RESULTS

Previous findings on SLE susceptible alleles were well replicated in the two GWAS. The SNPs on HLA class II (rs9270970, A>G, OR = 1.82, p value = 3.61E-26), STAT4 (rs7582694, C>G, OR = 1.57, p value = 8.21E-16), GTF2I (rs73366469, A>G, OR = 1.73, p value = 2.42E-11), and FAM167A-BLK allele (rs13277113, A>G, OR = 0.68, p value = 1.58E-09) were significantly associated with SLE in Thai population. Meta-analysis of the two GWAS identified a novel locus at the FBN2 that was specifically associated with SLE in the Thai population (rs74989671, A>G, OR = 1.54, p value = 1.61E-08). Functional analysis showed that rs74989671 resided in a peak of H3K36me3 derived from CD14+ monocytes and H3K4me1 from T lymphocytes. In addition, we showed that the PRS model trained from the Chinese population could be applied in individuals of Thai ancestry, with the area under the receiver-operator curve (AUC) achieving 0.76 for this predictor.

CONCLUSIONS

We demonstrated the genetic architecture of SLE in the Thai population and identified a novel locus associated with SLE. Also, our study suggested a potential use of the PRS model from the Chinese population to estimate the disease risk for individuals of Thai ancestry.