TNFα -857 C/T and TNFR2 +587 T/G polymorphisms are associated with cystic fibrosis in Iranian patients

Lung Inflammatory Genes in Cystic Fibrosis and Their Relevance to Cystic Fibrosis Transmembrane Conductance Regulator Modulator Therapies

Cystic fibrosis (CF) is a monogenic syndrome determined by over 2000 mutations in the CF Transmembrane Conductance Regulator (CFTR) gene harbored on chromosome 7. In people with CF (PWCF), lung disease is the major determinant of morbidity and mortality and is characterized by a clinical phenotype which differs in the presence of equal mutational assets, indicating that genetic and environmental modifiers play an important role in this variability. Airway inflammation determines the pathophysiology of CF lung disease (CFLD) both at its onset and progression. In this narrative review, we aim to depict the inflammatory process in CF lung, with a particular emphasis on those genetic polymorphisms that could modify the clinical outcome of the respiratory disease in PWCF. The natural history of CF has been changed since the introduction of CFTR modulator therapies in the clinical arena. However, also in this case, there is a patient-to-patient variable response. We provide an overview on inflammatory/immunity gene variants that affect CFLD severity and an appraisal of the effects of CFTR modulator therapies on the inflammatory process in lung disease and how this knowledge may advance the optimization of the management of PWCF.

Association of tumor necrosis factor-alpha promoter region gene polymorphism at positions -308G/A, -857C/T, and -863C/A with etanercept response in Iraqi rheumatoid arthritis patients

Objectives

This study aims to evaluate the association between polymorphisms in the promoter region of the tumor necrosis factor-alpha (TNF-α) gene at locations -308G/A, -857C/T, and -863C/A with the tendency of being non-responder to etanercept.

Patients and methods

Between October 2020 and August 2021, a total of 80 patients (10 males, 70 females; mean age: 50 years; range, 30 to 72 years) with rheumatoid arthritis (RA) receiving etanercept for at least six months were included. The patients were divided into two groups responders and non-responders, based on their response after six months of continuous treatment. Following polymerase chain reaction amplification of the extracted deoxyribonucleic acid, sequencing by Sanger method was performed to identify the polymorphism at the TNF-α promoter region.

Results

In the responder group, the GG genotype of (-308G/A) and the AA genotype of (-863C/A) were both significantly present. The CC genotype of (-863C/A) was significantly present in the non-responders group. The CC of (-863C/A) SNP was the only genotype that appeared to increase the likelihood of being resistant to etanercept. The GG genotype of (-308G/A) was negatively correlated with the likelihood of being a non-responder. The (-857CC) and (-863CC) genotypes were significantly more prevalent in the non-responders group.

Conclusion

The presence of the (-863CC) genotype, alone or in combination with (-857CC), is linked to an increased likelihood of becoming a non-responder to etanercept. The GG genotype of -308G/A and the AA genotype of -863C/A significantly increase the likelihood of becoming responder to etanercept.

TNFRSF1B and TNF variants are associated with differences in soluble TNF receptors' levels in patients with severe COVID-19

BACKGROUND

The impact of genetic variants in the expression of TNF-α and its receptors in COVID-19 severity has not been previously explored. We evaluated the association of TNF (rs1800629 and rs361525), TNFRSF1A (rs767455 and rs1800693), and TNFRSF1B (rs1061622 and rs3397) variants with COVID-19 severity, assessed as invasive mechanical ventilation (IMV) requirement, and the plasma levels of soluble TNF-α, TNFR1, and TNFR2 in patients with severe COVID-19.

METHODS

The genetic study included 1,353 patients. Taqman assays assessed the genetic variants. ELISA determined the soluble TNF, TNFR1, and TNFR2 in plasma samples from 334 patients.

RESULTS

Patients carrying TT (TNFRSF1B rs3397) exhibited lower PaO2/FiO2 levels than those with CT+CC genotypes. Differences in plasma levels of TNFR1 and TNFR2 were observed according to the genotype of TNFRSF1B rs1061622, TNF rs1800629, and rs361525. According to the studied genetic variants, there were no differences in the soluble TNF-α levels. Higher soluble TNFR1 and TNFR2 levels were detected in patients with COVID-19 requiring IMV.

CONCLUSION

Genetic variants in TNF and TNFRSFB1 influence the plasma levels of soluble TNFR1 and TNFR2, implicated in the COVID-19 severity.

Mucosal Immunity in Cystic Fibrosis

The highly complex and variable genotype-phenotype relationships observed in cystic fibrosis (CF) have been an area of growing interest since the discovery of the CF transmembrane conductance regulator (CFTR) gene >30 y ago. The consistently observed excessive, yet ineffective, activation of both the innate and adaptive host immune systems and the establishment of chronic infections within the lung, leading to destruction and functional decline, remain the primary causes of morbidity and mortality in CF. The fact that both inflammation and pathogenic bacteria persist despite the introduction of modulator therapies targeting the defective protein, CFTR, highlights that we still have much to discover regarding mucosal immunity determinants in CF. Gene modifier studies have overwhelmingly implicated immune genes in the pulmonary phenotype of the disease. In this context, we aim to review recent advances in our understanding of the innate and adaptive immune systems in CF lung disease.

Cystic Fibrosis: Systems Biology Analysis from Homozygous p.Phe508del Variant Patients' Samples Reveals Perturbations in Tissue-Specific Pathways

Cystic fibrosis (CF) is an autosomal recessive disorder, caused by diverse genetic variants for the CF transmembrane conductance regulator (CFTR) protein. Among these, p.Phe508del is the most prevalent variant. The effects of this variant on the physiology of each tissue remains unknown. This study is aimed at predicting cell signaling pathways present in different tissues of fibrocystic patients, homozygous for p.Phe508del. The study involved analysis of two microarray datasets, E-GEOD-15568 and E-MTAB-360 corresponding to the rectal and bronchial epithelium, respectively, obtained from the ArrayExpress repository. Particularly, differentially expressed genes (DEGs) were predicted, protein-protein interaction (PPI) networks were designed, and centrality and functional interaction networks were analyzed. The study reported that p.Phe508del-mutated CFTR-allele in homozygous state influenced the whole gene expression in each tissue differently. Interestingly, gene ontology (GO) term enrichment analysis revealed that only “neutrophil activation” was shared between both tissues; however, nonshared DEGs were grouped into the same GO term. For further verification, functional interaction networks were generated, wherein no shared nodes were reported between these tissues. These results suggested that the p.Phe508del-mutated CFTR-allele in homozygous state promoted tissue-specific pathways in fibrocystic patients. The generated data might further assist in prediction diagnosis to define biomarkers or devising therapeutic strategies.

Association of TNF-α -308G > A polymorphism with susceptibility to tendinopathy in athletes: a case-control study

BACKGROUND

High levels of the tumor necrosis factor alpha (TNF-α) induce apoptosis and pro-inflammatory effects for primary degeneration of tendon and development of tendinopathy. The aim of this study was to investigate the association between the TNF-α polymorphisms and tendinopathy in athletes.

METHODS

Two hundred and seventy athletes (135 tendinopathy cases and 135 controls) were included and genotyped (TNF-α -1031T > C; -857 C > T; -308G > A) using TaqMan validated assays. The association of the polymorphisms with tendinopathy was evaluated by a multivariate logistic regression model, using odds ratios (OR) and 95 % confidence intervals (CI).

RESULTS

The variant allele - 308 A was significantly associated with patellar (OR: 1.9; 95 % CI: 1.01-3.6) or Achilles tendinopathies (OR: 2.7; 95 % CI: 1.1-6.7). No significant differences were found in allele or genotype distributions of the - 1031T > C and - 857 C > T polymorphisms between cases and controls. TNF-α TCA haplotype was associated with increased tendinopathies risk, either considering all cases (OR: 2.6, 95 % CI: 1.3-5.3), patellar (OR: 3.3, 95 % CI: 1.5-7.3), rotator cuff (OR: 3.1, 95 % CI: 1.4-7.2) or Achilles tendinopathies (OR: 3.8, 95 % CI: 1.1-12.7).

CONCLUSIONS

These results suggest that the TNF-α polymorphisms could influence the susceptibility to developing tendinopathy among athletes. Knowledge of the TNF-α polymorphisms associated to tendinopathy in athletes can further understanding of the inflammatory role in the early stages of the disease and contribute for sports injury surveillance programmes, in which athletes with TNF-α TCA haplotype could be early subjected to cryotherapy after training and competition to avoid tendinopathy development.

Association of IL-10 gene promoter polymorphisms with susceptibility to pseudoexfoliation syndrome, pseudoexfoliative and primary open-angle glaucoma

Background

The involvement of cytokines in pathogenesis of pseudoexfoliation syndrome and glaucoma has been demonstrated in several studies. The aim of the present study was to explore the association between three promoter polymorphisms −592C/A (rs1800872), − 819C/T (rs1800871) and -1082A/G (rs1800896) of interleukin 10 (IL-10) gene with susceptibility to pseudoexfoliation syndrome (PEX), pseudoexfoliative glaucoma (PEXG), and primary open-angle glaucoma (POAG).

Methods

In this study, 114 PEX, 118 PEXG, 114 POAG patients and 126 healthy individuals from Iranian population were participated. Detailed ophthalmic examinations by an ophthalmologist including slit-lamp bio-microscopic examination, dilated examination of the lens, gonioscopy, and funduscopy were carried out on patients and controls. Genomic DNA was extracted from the blood samples and ARMS–PCR was performed to detect promoter polymorphisms of IL-10.

Results

In all three SNPs studied, there was a significant difference in the genotype distribution between patients and control subjects. Results revealed that the AA genotype of IL-10 -592C/A SNP is associated with PEX. However, TT genotype of −819C/T and AA genotype of -1082A/G SNP are significantly associated with susceptibility to either PEX or PEXG and POAG disorders. Furthermore, the ACC haplotype containing the IL-10 -1082A allele was associated with PEX (P = 0.02, OR = 5.76, 95% CI = 5.17–24.49), PEXG (P = 0.006, OR = 7.54, 95% CI = 6.62–30.76) and POAG (P = 0.003, OR = 8.11, 95% CI = 7.13–33.15).

Conclusions

Our results demonstrated that IL-10 gene promoter polymorphisms are associated with susceptibility to PEX, PEXG and POAG in Iranian population. Considering the fact that IL-10 polymorphisms are associated with various IL-10 expressions, further research is needed to explain its involvement in these disorders and the formation of extracellular fibrillar amyloid deposits in PEX and PEXG.