Association of IL17A and IL17F genes with rheumatoid arthritis disease and the impact of genetic polymorphisms on response to treatment

Tumor necrosis factor alpha induced protein 3, interleukin 10, tumor necrosis factor alpha, and interleukin 17 F genes polymorphisms in Algerian patients with rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) is a systemic autoimmune disease with chronic inflammation. Its pathogenesis involves immunological, genetic, and environmental factors. We investigate the association between Tumor Necrosis Factor α Protein 3 (TNFAIP3), Interleukin 10 (IL10), Tumor Necrosis Factor α (TNF α), and Interleukin 17 F (IL17F) polymorphisms with susceptibility to RA.

METHODS AND RESULTS

191 patients with RA diagnosed according to the American College of Rheumatology (ACR)/ European League Against Rheumatism (EULAR) classification and 190 healthy subjects were recruited. Rheumatoid factor (RF), anti-citrullinated peptide antibodies (ACPA), and C-reactive protein (CRP) were measured. Genotyping of the polymorphisms was performed by real-time PCR. Analysis of the allelic frequencies of TNFAIP3 showed a positive association OR (95% CI) = 1.46 (1.01-2.09); p = 0.04, but failed to meet the criteria of significance after Bonferroni Correction. The genotypic and allelic distribution of the IL10, IL17F, and TNFα showed no significant difference when comparing the RA group with controls. Furthermore, the genotype codominant model shows a moderate positive association in the presence of ACPA (OR (95% CI) = 2.82 (1.22-6.24); p = 0.01. None of the polymorphisms studied was associated with RF and CRP production.

CONCLUSION

Our results show that there is a tendency for the AG genotype of IL10-1082 to be associated with the production of ACPA in patients with RA. None of the variants studied were associated with RA susceptibility in Algerians.

Association between Interleukin-17F 7488A/G and 7383A/G polymorphisms and susceptibility to juvenile idiopathic arthritis

BACKGROUND

Interleukin-17F (IL-17F), one of the cytokines, is crucial in the pathophysiology of juvenile idiopathic arthritis (JIA). Therefore, we aimed to determine the relation between IL17F 7488A/G and IL17F 7383A/G single-nucleotide polymorphisms and JIA susceptibility and to explain their impact on the disease activity.

METHODS

Genomic DNA of 70 patients with JIA and 70 age and sex-matched controls were extracted and typed for IL17F 7488A/G and IL17F 7383A/G single-nucleotide polymorphisms, using polymerase chain reaction with sequence-specific primers method, and compared between patients and controls.

RESULTS

When compared to AA participants, children with the AG genotype of the IL17F 7488A/G and IL17F 7383A/G polymorphisms showed a substantially greater risk of JIA. Furthermore, children with the G allele were 2.8 folds more likely to have JIA than the A allele for IL17F 7488A/G polymorphism and 3.72 folds for IL17F 7383A/G polymorphism. Children with AG genotype of IL17F 7383A/G polymorphism were far more likely to have high activity JIA.

CONCLUSIONS

The G allele of both IL17F 7488A/G and IL17F7383 A/G polymorphisms is associated with increased JIA susceptibility, and JIA at High Disease Activity was more likely to develop in AG subjects of the IL17F 7383 A/G polymorphism.

IMPACT

The relationship between Interleukin-17F 7488A/G and 7383A/G polymorphisms and risk for JIA has not been recognized before. Impact of Interleukin-17F 7488A/G and 7383A/G genotypes on JIA disease activity. The G allele of both IL17F 7488A/G and IL17F7383 A/G polymorphisms are associated with increased JIA susceptibility. AG genotype of Interleukin-17F 7383 A/G polymorphism compared to AA patients, had a higher probability of developing JIA at a High Disease Activity (HDA) level.

Association of IL-17F rs2397084 (E126G), rs11465553 (V155I) and rs763780 (H161R) variants with rheumatoid arthritis and their effects on the stability of protein

Interleukin-17F (IL-17F), considered a pro-inflammatory cytokine, has been shown to contribute to skeletal tissue degradation and hence chronic inflammation in rheumatoid arthritis (RA). In this study we utilized bioinformatics tools to analyze the effect of three exonic SNPs (rs2397084, rs11465553, and rs763780) on the structure and function of the IL-17F gene, and evaluated their association with RA in Pakistani patients. The predicted deleterious and damaging effects of identified genetic variants were assessed through the utilization of multiple bioinformatics tools including PROVEAN, SNP&GO, SIFT, and PolyPhen2. Structural and functional effects of these variants on protein structures were evaluated through the use of additional tools such as I-Mutant, MutPred, and ConSurf. Three-dimensional (3D) models of both the wild-type and mutant proteins were constructed through the utilization of I-TASSER software, with subsequent structural comparisons between the models conducted through the use of the TM-align score. A total of 500 individuals, 250 cases and 250 controls, were genotyped through Tri-ARMS-PCR method and the resultant data was statistically analyzed using various inheritance models. Our bioinformatics analysis showed significant structural differences for wild type and mutant protein (TM-scores and RMSD values were 0.85934 and 2.34 for rs2397084 (E126G), 0.87388 and 2.49 for rs11465553 (V155I), and 0.86572 and 0.86572 for rs763780 (H161R) with decrease stability for the later. Overall, these tools enabled us to predict that these variants are crucial in causing disease phenotypes. We further tested each of these single nucleotide variants for their association with RA. Our analysis revealed a strong positive association between the genetic variant rs763780 and the risk of developing rheumatoid arthritis (RA) at both the genotypic and allelic levels. The genotypic association was statistically significant[χ2 = 111.8; P value <0.0001], as was the allelic level [OR 3.444 (2.539-4.672); P value 0.0008]. These findings suggest that the presence of this genetic variant may increase the susceptibility to RA. Similarly, we observed a significant distribution of the genetic variant rs11465553 at the genotypic level [χ2 = 25.24; P value = 0.0001]. However, this variant did not show a significant association with RA at the allelic level [OR = 1.194 (0.930-1.531); P value = 0.183]. However, the distribution of variant rs2397084 was more or less random across our sample with no significant association either at genotypic and or allelic level. Put together, our association study and in silico prediction of decreasing of IL17-F protein stabilty confirmed that two SNPs, rs11465553 and rs763780 are crucial to the suscetibility of and showed that these RA in Pakistani patients.

Associations of IL-17 and IL-17 receptor polymorphisms with Behçet's disease in Denizli Province of Turkey

Although the etiopathogenesis of Behçet's disease is not known, studies conducted in different populations show that it is a multifactorial disease that is thought to develop as a result of the interaction of environmental and genetic factors. IL-17 is thought to induce the neutrophilic inflammation and the tissue damage mediated by immune response in patients. Polymorphisms in the gene region encoding IL-17 and IL-17R molecules may play a critical role in the pathogenesis of the disease and contribute to the elucidation of disease mechanism. We aimed to show the association of IL-17A, IL-17F, and IL-17RC polymorphisms and haplotypes in Behçet's disease patients and its clinical features. We genotyped IL-17A (rs4711998 (A/G), rs8193036 (C/T), rs2275913 (A/G), rs3819025 (A/G), rs8193038 (A/G), rs3804513 (A/T), rs1974226 (C/T), rs3748067 (C/T)); IL-17F (rs763780 (T/C), rs2397084 (T/C)); and IL-17R (IL-17RC) (rs708567 (C/T)) polymorphisms in 88 patients with Behçet's disease and 133 healthy controls using PCR-RFLP-based approach. The results of our study showed that polymorphisms of IL-17A, rs8193036 (C/T), rs3819025 (G/A), rs3804513 (A/T), IL-17F rs2397084 (T/C), and IL-17RC rs708567 (C/T) are associated with the susceptibility to the BD. When the haplotype distributions of all loci of IL-17Aand IL-17A/IL-17F together were examined and in contrast to the data obtained from the controls, the GTGGAACC (27.84%) and GTGGAACCTT (25.57%) have the highest frequencies. In conclusion, the allele and genotype frequency differences of the IL-17A, IL-17F, and IL-17R and haplotype frequencies between Behçet's disease and controls indicate that the genetic structure of Behçet's disease may be different.

Interleukin-17 Genes Polymorphisms are Significantly Associated with Cutaneous T-cell Lymphoma Susceptibility

Tumour microenvironment has an important effect on the progression of cutaneous T-cell lymphomas. Using PCR with sequence-specific primers, this study analysed single-nucleotide polymorphisms in the interleukin-17 genes of 150 patients with cutaneous T-cell lymphoma. GG homozygote rs8193036 A/G of interleukin-17A gene occurred less commonly in the cutaneous T-cell lymphoma group; however, patients with this single-nucleotide polymorphism experience significantly intense pruritus. Conversely, the rs2397084 AG heterozygote of interleukin-17F is more common in the lymphoma population. In addition, there were significant differences in the frequencies of interleukin-17 genotypes when comparing early (Ia to IIa) and advanced stages (IIb, III and IV) of this neoplasms. A similar result has been shown in comparison between Sézary syndrome and mycosis fungoides. The current data may serve as a possible explanation for the increased bacterial infection rates in the course of cutaneous T-cell lymphoma, especially caused by Staphylococcus aureus. In summary, specific single-nucleotide polymorphisms occur with different frequencies between cutaneous T-cell lymphoma and healthy patients. Moreover, genetic predisposition of several interleukin-17 single-nucleotide polymorphisms may be a factor causing impaired immune defence in cutaneous lymphomas.

Pharmacogenomics of Monoclonal Antibodies for the Treatment of Rheumatoid Arthritis

Precision medicine refers to a highly individualized and personalized approach to patient care. Pharmacogenomics is the study of how an individual’s genomic profile affects their drug response, enabling stable and effective drug selection, minimizing side effects, and maximizing therapeutic efficacy. Rheumatoid arthritis (RA) is an autoimmune disease that causes chronic inflammation in the joints. It mainly starts in peripheral joints, such as the hands and feet, and progresses to large joints, which causes joint deformation and bone damage due to inflammation of the synovial membrane. Here, we review various pharmacogenetic studies investigating the association between clinical response to monoclonal antibody therapy and their target genetic polymorphisms. Numerous papers have reported that some single nucleotide polymorphisms (SNPs) are related to the therapeutic response of several monoclonal antibody drugs including adalimumab, infliximab, rituximab, and tocilizumab, which target tumor necrosis factor (TNF), CD20 of B-cells, and interleukin (IL)-6. Additionally, there are some pharmacogenomic studies reporting on the association between the clinical response of monoclonal antibodies having various mechanisms, such as IL-1, IL-17, IL-23, granulocyte-macrophage colony-stimulating factor (GM-CSF) and the receptor activator of nuclear factor-kappa B (RANK) inhibition. Biological therapies are currently prescribed on a “trial and error” basis for RA patients. If appropriate drug treatment is not started early, joints may deform, and long-term treatment outcomes may worsen. Pharmacogenomic approaches that predict therapeutic responses for RA patients have the potential to significantly improve patient quality of life and reduce treatment costs.

Proinflammatory Cytokines (IL-1, -6, -8, -15, -17, -18, -23, TNF-α) Single Nucleotide Polymorphisms in Rheumatoid Arthritis-A Literature Review

Conducted studies highlight that a mixture of genetic and environmental factors is responsible for rheumatoid arthritis (RA) development. This study aimed to analyze the available literature for the relationship between, on the one hand, single-nucleotide polymorphisms (SNPs) in the proinflammatory cytokines genes interleukin-1 (IL-1), -6, -8, -15, -17, -18, and -23, and tumor necrosis factor-alpha (TNF-α), and on the other hand, RA susceptibility, severity, and patients' response to applied treatment. The PubMed database was searched for sources. Preference was given to articles which were published within the past 20 years. Data indicate that the relationship between selected SNPs in proinflammatory cytokines genes and susceptibility to developing RA is inconclusive, and it depends on the ethnicity of the population. Although the allelic and genotypic frequencies of many SNPs in proinflammatory cytokines genes analyzed did not differ between RA patients and healthy controls, deeper analysis showed that these polymorphisms have a relationship with clinicopathological features of RA. SNPs in proinflammatory cytokines genes also "modify patients' response" to applied treatment. Further studies, on larger cohorts of subjects and in different populations, should be conducted to elucidate the role of SNPs in IL-1, -6, -8, -15, -17, -18, and -23, and TNF-α genes in RA patients.

Characteristics of the Gut Microbiome and Its Relationship With Peripheral CD4+ T Cell Subpopulations and Cytokines in Rheumatoid Arthritis

This study investigated the association between intestinal microbiota abundance and diversity and cluster of differentiation (CD)4⁺ T cell subpopulations, cytokine levels, and disease activity in rheumatoid arthritis RA. A total of 108 rheumatoid arthritis (RA) patients and 99 healthy control (HC) subjects were recruited. PICRUSt2 was used for functional metagenomic predictions. Absolute counts of peripheral CD4⁺ T cell subpopulations and cytokine levels were detected by flow cytometry and with a cytokine bead array, respectively. Correlations were analyzed with the Spearman rank correlation test. The results showed that the diversity of intestinal microbiota was decreased in RA patients compared to HCs. At the phylum level, the abundance of Firmicutes, Fusobacteriota, and Bacteroidota was decreased while that of Actinobacteria and Proteobacteria was increased and at the genus level, the abundance of Faecalibacterium, Blautia, and Escherichia-Shigella was increased while that of Bacteroides and Coprococcus was decreased in RA patients compared to HC subjects. The linear discriminant analysis effect size indicated that Bifidobacterium was the most significant genus in RA. The most highly enriched Kyoto Encyclopedia of Genes and Genomes pathway in RA patients was amino acid metabolism. The relative abundance of Megamonas, Monoglobus, and Prevotella was positively correlated with CD4⁺ T cell counts and cytokine levels; and the relative numbers of regulatory T cells (Tregs) and T helper (Th17)/Treg ratio were negatively correlated with disease activity in RA. These results suggest that dysbiosis of certain bacterial lineages and alterations in gut microbiota metabolism lead to changes in the host immune profile that contribute to RA pathogenesis.

Proteomic Approaches to Defining Remission and the Risk of Relapse in Rheumatoid Arthritis

Objectives

Patients with Rheumatoid Arthritis (RA) are increasingly achieving stable disease remission, yet the mechanisms that govern ongoing clinical disease and subsequent risk of future flare are not well understood. We sought to identify serum proteomic alterations that dictate clinically important features of stable RA, and couple broad-based proteomics with machine learning to predict future flare.

Methods

We studied baseline serum samples from a cohort of stable RA patients (RETRO, n = 130) in clinical remission (DAS28<2.6) and quantified 1307 serum proteins using the SOMAscan platform. Unsupervised hierarchical clustering and supervised classification were applied to identify proteomic-driven clusters and model biomarkers that were associated with future disease flare after 12 months of follow-up and RA medication withdrawal. Network analysis was used to define pathways that were enriched in proteomic datasets.

Results

We defined 4 proteomic clusters, with one cluster (Cluster 4) displaying a lower mean DAS28 score (p = 0.03), with DAS28 associating with humoral immune responses and complement activation. Clustering did not clearly predict future risk of flare, however an XGboost machine learning algorithm classified patients who relapsed with an AUC (area under the receiver operating characteristic curve) of 0.80 using only baseline serum proteomics.

Conclusions

The serum proteome provides a rich dataset to understand stable RA and its clinical heterogeneity. Combining proteomics and machine learning may enable prediction of future RA disease flare in patients with RA who aim to withdrawal therapy.

Association between the interleukin (IL)-17A rs2275913 polymorphism and rheumatoid arthritis susceptibility: a meta-analysis and trial sequential analysis

Objective

This meta-analysis was conducted to investigate the relationship between the interleukin (IL)-17A rs2275913 polymorphism and rheumatoid arthritis (RA) susceptibility.

Methods

Eligible studies were retrieved from PubMed, Embase, and Web of Science. The fixed- or random-effects model was used to calculate the pooled odds ratios (ORs) and 95% confidence intervals (95%CIs) on the basis of heterogeneity.

Results

Overall, 11 studies containing 4019 RA patients and 4137 controls were included in this meta-analysis. The results suggested a significant association between the IL-17A rs2275913 polymorphism and RA susceptibility in the overall population (allelic model A vs. G: OR = 0.89, 95%CI: 0.83–0.95; heterozygote model GA vs. GG: OR = 0.87, 95%CI: 0.78–0.96; homozygote model AA vs. GG: OR = 0.82, 95%CI: 0.71–0.96; dominant model GA + AA vs. GG: OR = 0.86, 95%CI: 0.78–0.94). In the subgroup analyses, the IL-17A rs2275913 polymorphism was significantly associated with RA risk in Europeans (allelic model A vs. G: OR = 0.87, 95%CI: 0.78–0.97; heterozygote model GA vs. GG: OR = 0.79, 95%CI: 0.68–0.93; dominant model GA + AA vs. GG: OR = 0.79, 95%CI: 0.68–0.92), but not in Africans or Americans.

Conclusion

This study suggests that the IL-17A rs2275913 polymorphism is significantly associated with RA susceptibility in Europeans.

INPLASY registration number: INPLASY202170056.

Polymorphisms within Genes Coding for IL-17A and F and Their Receptor as Clinical Hallmarks in Ankylosing Spondylitis

IL-17A and IL-17F together with their coreceptor (IL-17RA/RC) were reported to play a significant role in the pathogenesis of spondyloarthritis. The group of axial spondyloarthritis comprises ankylosing spondylitis (AS), a rheumatic disease characterized by chronic inflammation of the joints in the spine. This study is aimed at investigating IL-17A, IL-17F, IL-17RA, and IL-17RC polymorphisms as potential biomarkers of disease susceptibility, clinical parameters, and anti-TNF treatment outcome in a cohort of Polish ankylosing spondylitis patients. In total, 328 subjects, including 138 AS patients and 190 healthy volunteers, participated in the study. Genotyping of IL-17A rs2275913 (G/A), IL-17F rs763780 (A/G), IL-17RA rs4819554 (A/G), and IL-17RC rs708567 (G/A) was performed on real-time PCR instrument using LightSNiP assays. No significant differences were revealed in genotype and allele distribution between patients and controls despite the association of the IL-17RC rs708567 AA homozygosity with the earlier onset of the disease. Moreover, some relationships between IL-17F rs763780 and IL-17RA rs4819554 polymorphisms with clinical parameters related to the disease activity and anti-TNF treatment outcome were observed. IL-17F rs763780 G allele was found to be associated with high disease activity and BASDAI after 6 months and poor response to the treatment while higher VAS values were more common among IL-17RA rs4819554 G variant carriers. In conclusion, the IL-17F rs763780 polymorphism should be considered as a promising biomarker of disease activity and anti-TNF treatment outcome. The IL-17RA rs48419554 G allele may serve as a potential marker of disease severity in Polish AS patients.

IL17F: A Possible Risk Marker for Spondyloarthritis in HLA-B*27 Negative Brazilian Patients

HLA-B*27 is an important marker for spondyloarthritis (SpA), however, many SpA patients are HLA-B*27 negative. Thus, the aim of this study was to investigate the influence of IL17, TNF and VDR gene polymorphisms in SpA patients who were HLA-B*27 negative. This case-control study was conducted in 158 patients [102 patients with ankylosing spondylitis (AS) and 56 with psoriatic arthritis (PsA)] and 184 controls. HLA-B*27 genotyping was performed using PCR-SSP and IL17A (rs2275913), IL17F (rs763780), TNF-308 (rs1800629), TNF-238 (rs361525), FokI C>T (rs2228570), TaqI C>T (rs731236), ApaI A>C (rs7975232), and BsmI C>T (rs1544410) using PCR-RFLP. Statistical analyses were performed by Chi-square and logistic regression using OpenEpi and SNPStats software. The IL17F C allele frequency was higher in patients with SpA, AS and PsA compared to controls. The IL17F T/C genotype frequency was higher in SpA patients in an overdominant inheritance model and when men and women were separately analyzed. IL17A_IL17F AC haplotype was significantly associated to the risk for SpA patients. As for VDR, the ApaI a/a was a potential risk factor for SpA in men. In conclusion, IL17F C variant contributed to the risk of SpA in Brazilian patients who were HLA-B*27 negative and could be a potential marker for SpA.

Novel approaches to develop biomarkers predicting treatment responses to TNF-blockers

Introduction: Chronic inflammatory diseases (CIDs) cause significant morbidity and are a considerable burden for the patients in terms of pain, impaired function, and diminished quality of life. Important progress in CID treatment has been obtained with biological therapies, such as tumor-necrosis-factor blockers. However, more than a third of the patients fail to respond to these inhibitors and are exposed to the side effects of treatment, without the benefits. Therefore, there is a strong interest in developing tools to predict response of patients to biologics. Areas covered: The authors searched PubMed for recent studies on biomarkers for disease assessment and prediction of therapeutic responses, focusing on the effect of TNF blockers on immune responses in spondyloarthritis (SpA), and other CID, in particular rheumatoid arthritis and inflammatory bowel disease. Conclusions will be drawn about the possible development of predictive biomarkers for response to treatment. Expert opinion: No validated biomarker is currently available to predict treatment response in CID. New insight could be generated through the development of new bioinformatic modeling approaches to combine multidimensional biomarkers that explain the different genetic, immunological and environmental determinants of therapeutic responses.

Single Nucleotide Polymorphism in the IL17A Gene Is Associated with Interstitial Lung Disease Positive to Anti-Jo1 Antisynthetase Autoantibodies

Antisynthetase syndrome (ASSD) is a rare multisystemic connective tissue disease affecting the skin, joints, muscles, and lungs, characterized by anti-aminoacyl transfer-RNA-synthetases (anti-tRNA) autoantibodies production, being anti-Jo1 the most frequent. We included one-hundred twenty-one ASSD patients and 340 healthy subjects (HS), and also, we divided the case group into anti-Jo1 and non-anti-Jo1. Two single nucleotide polymorphisms (SNPs) in the IL17A gene were evaluated. Anti-Jo1 was the most common anti-tRNA antibody in our cohort, and the most frequent tomographic pattern was non-specific interstitial pneumonia (NSIP). Anti-Jo1 ASSD patients had higher levels of creatine phosphokinase than the non-anti-Jo1 group. Significant differences in genotype frequencies with rs8193036/CC between anti-Jo1 vs. non-anti-Jo1 ASSD patients (p < 0.001), maintaining the association after Bonferroni correction (p = 0.002). Additionally, in the anti-Jo1 group vs. HS comparison, we found a statistically significant difference with the same SNP (p = 0.018, OR = 2.91, 95% CI = 1.15-7.35), maintaining the association after Bonferroni correction (p = 0.036). The rs8193036/CC genotype in IL17A is associated with ASSD patients with anti-Jo1. Also, anti-Jo1 and non-anti-Jo1 patients display differences in genotype frequencies.

Association of interleukin-17 gene polymorphisms with the onset of Rheumatoid Arthritis

Rheumatoid Arthritis (RA) is an autoimmune disorder where multiple cytokines including IL-17A and IL-17F produced by T helper cell 17 (Th17), contribute to its pathogenesis. By initiating inflammatory responses in joints Th17 act as pathogenic driver leading to bone and cartilage destruction in RA patients. Hence, the planned study was aimed to estimate IL-17 gene polymorphism association with RA susceptibility in Pakistani population. The present study included 100 subjects (50 RA patients and 50 healthy controls). Blood samples were taken and DNA was isolated for genotyping purpose. Chi square and Logistic regression analysis was performed to check the association of selected SNPs with RA. For rs2397084 and rs763780 polymorphism T allele acted as significant risk factor as compared to the reference C allele. TT vs. CC comparison in rs2397084 showed that T allele is a risk factor (OR 5.538; 95%Cl 1.757-17.458) in RA susceptibility. In case of rs763780 heterozygous CT (OR 10.80; 95% Cl 3.736-31.218) and homozygous mutant TT (OR 7.50; 95% Cl 2.360-23.831) genotypes proved to be a potential risk for RA patients. The significant differences in allelic and genotypic frequencies were observed for both SNPs. While for rs2275913 significantly varied frequency was observed only for dominant model of inheritance and non significant differences were seen at allelic level. Variation at all these three polymorphic sites substituted mutant amino acids leading to further functional changes in protein structure. Three polymorphic sites rs2275913, rs763780 and rs2397084 positioned on IL-17 gene were significantly strong factors in RA incidence among Pakistani population as they alter normal function of inflammatory cytokine IL-17.

Immunogenetic markers in IL17F predict the risk of metastases spread and overall survival in rectal cancer patients treated with neoadjuvant chemoradiotherapy

BACKGROUND AND PURPOSE

The role of the immune system in tumor response to chemo-radiotherapy (CRT) is an emerging issue. This work aimed at identifying predictive and prognostic immunogenetic variants in LARC patients after preoperative (po)-CRT and surgery.

MATERIALS AND METHODS

A set of 192 polymorphisms in 34 candidate genes involved in the regulation of the immune response signalling network, was selected and analyzed in 370 LARC patients treated with po-CRT and surgery, split into a Test Set (n = 233) and a Validation Set (n = 137). Immunogenetic markers were selected based on a concordant significant effect on 2-year relapse-free survival (2-yrRFS) (bootstrapped P < 0.05) in both patients Sets. The effect of the selected immunogenetic variants on 5-year metastases-free (5yrMFS), 5-year disease-free (5yrDFS), and 10-year overall (10yrOS) survival was tested in the entire Set of 370 patients.

RESULTS

Two immunogenetic IL17F (IL17F-rs641701 and IL17F-rs9463772) markers predictive of 2yrRFS, 5yrDFS, 5yrMFS, and 10yrOS were identified. The combination of tumor regression grade (TRG) and patients genotype for IL17F-rs641701 and IL17F-rs9463772 allowed the identification of subgroups of patients with differential prognosis in term of both 5yrDFS (HR 11.29, P-value <0.001, and HR 5.86, P-value = 0.001, respectively) and 10yrOS (HR 7.07, P-value = 0.005, and HR 6.05, P-value = 0.002, respectively).

CONCLUSION

IL17F-rs641701 and IL17F-rs9463772 were highlighted as promising immunogenetic markers significantly associated with the prognosis of LARC patients. After a prospective validation of the herein reported findings, the combination of TRG and patients genotype should be considered to provide additional stratification criteria for the selection of a personalized multimodality treatment.

Association between IL-17A and IL-17F gene polymorphism and susceptibility in inflammatory arthritis: A meta-analysis

OBJECTIVES

The association between Interleukin (IL)-17A and IL-17F gene polymorphism with inflammatory arthritis were inconsistent among previous studies. This meta-analysis aimed to determine the association between IL-17A and IL-17F gene polymorphism with ankylosing spondylitis (AS), osteoarthritis (OA) and rheumatoid arthritis (RA).

METHODS

We searched Medline up to August 2019. The summary Odds Ratio (OR) with corresponding 95% confidence intervals (CIs) was calculated to evaluate the relationship between IL-17A and IL-17F gene polymorphism with genetic susceptibility of AS, OA and RA.

RESULTS

A total of 19 studies with 5298 cases and 5675 healthy controls were included. There were significant associations between rs2275913 G allele with OA, RA susceptibility (P < .05) but not AS. Subgroup analysis by ethnicity indicated that rs763780 C allele was closely related to AS and OA in Caucasian populations (P < .001) but not Mongolians. A significant association between rs763780 and RA susceptibility was detected in Caucasian populations (P < .05).

CONCLUSION

IL-17F gene rs763780 C allele confers increased risk of inflammatory arthritis in Caucasians; IL-17A gene rs2275913 G allele are protective for OA susceptibility in Mongolians. More well-designed studies with larger sample size are needed to elucidate the role of IL-17A gene rs2275913 G allele in inflammatory arthritis, especially AS.

Genetic variants in IL17A and serum levels of IL-17A are associated with COPD related to tobacco smoking and biomass burning

IL-17A is an important pro-inflammatory cytokine involved in the inflammatory response in chronic obstructive pulmonary disease (COPD). To evaluate the role played by single nucleotide polymorphisms of IL17A and protein levels in susceptibility to COPD, 1,807 subjects were included in a case-control study; 436 had COPD related to tobacco smoking (COPD-S) and 190 had COPD related to biomass burning (COPD-BB). Six hundred fifty-seven smokers without COPD (SWOC) and 183 biomass burning-exposed subjects (BBES) served as the respective control groups. The CC genotype and C allele of rs8193036 were associated with COPD (COPD-S vs. SWOC: p < 0.05; OR = 3.01, and OR = 1.28, respectively), as well as a recessive model (p < 0.01; OR = 2.91). Significant differences in serum levels were identified between COPD-S vs. SWOC, COPD-S vs. COPD-BB, and SWOC vs. BBES (p < 0.01). By comparing genotypes in the COPD-BB group TT vs. CC and TC vs. CC (p < 0.05), we found lower levels for the CC genotype. Logistic regression analysis by co-variables was performed, keeping the associations between COPD-S vs. SWOC with both polymorphisms evaluated (p < 0.05), as well as in COPD-BB vs. BBES but with a reduced risk of exacerbation (p < 0.05). In conclusion, polymorphisms in IL17A are associated with COPD. Serum levels of IL-17A were higher in smokers with and without COPD.

IL-17, IL-21 and IL-22 polymorphisms in rheumatoid arthritis: A systematic review and meta-analysis

BACKGROUND

Rheumatoid Arthritis (RA) is an autoimmune systemic disease and in its pathogenesis participate several proinflammatory cytokines, including those produced by Th17 cells. We performed a systematic review aiming to assess the associations between polymorphisms in Th17 cytokines, namely IL-17A, IL-17F, IL-21 and IL-22, and susceptibility to RA.

METHODS

We searched three electronic databases (MEDLINE, Scopus and Web of Science) for observational studies assessing the association between susceptibility to RA (or its clinical presentation) and polymorphisms of the cytokines IL-17A, IL-17F, IL-21 and IL-22. From the selected studies, we extracted information on the studied polymorphisms, assessed outcomes, and demographic characteristics of participants. We performed random effects meta-analyses assessing the associations between susceptibility to RA and different genotypes of the IL-17A rs2275913, IL-17Frs763780 andIL-17Frs2397084polymorphisms. Primary studies' quality was assessed using the Q-Genie tool.

RESULTS

Fifteen studies were included in this systematic review. Five IL-17A polymorphisms were reported to be associated with susceptibility to RA. For the IL-17A rs2275913 polymorphism, our meta-analysis showed the AA genotype to be significantly associated with lower susceptibility to RA(OR = 0.76; 95%CI = 0.61-0.93;p = 0.01), while the opposite was observed for the GG genotype (OR = 1.20; 95%CI = 1.06-1.35;p = 0.01). Concerning IL-17Frs763780 polymorphism, theTT genotype was found to be significantly less frequent in RA patients(OR = 0.49; 95%CI = 0.31-0.77;p = 0.002), while the opposite was observed for the CT genotype (OR = 2.00; 95%CI = 1.03-3.87;p = 0.04). No significant associations were found regarding rs2397084polymorphisms. For IL-21, rs6822844 and rs4505848 were described to have significant associations with susceptibility to RA. No studies were found assessing IL-22 polymorphisms in RA.

CONCLUSIONS

IL-17A rs2275913 and IL-17F rs763780 polymorphisms are significantly associated with susceptibility to RA and with different clinical characteristics of this disease.

Methotrexate pharmacogenetics in the treatment of rheumatoid arthritis

For many decades, methotrexate (MXT) has remained the drug of choice in the treatment of rheumatoid arthritis (RA). Unfortunately, a considerable number of patients do not achieve an appropriate therapeutic response. Pharmacogenetics studies do not give usable results regarding differences in MTX response among RA patients. The mechanism of MTX action in RA is not completely understood. We present and discuss data regarding the molecular basis of folate and adenosine pathways, the most obvious MTX targets, to explain possible causes of therapy failure. The molecular basis of the disease could also have an impact on therapy outcomes and in this review we explore this. Finally, we make a short review of available pharmacogenetics study results.

The Non-synonymous rs763780 Single-Nucleotide Polymorphism in IL17F Gene Is Associated With Susceptibility to Tuberculosis and Advanced Disease Severity in Argentina

Th17 lymphocytes, that produce IL17A, IL17F, and IL22, play a crucial role during the immune response against Mycobacterium tuberculosis (Mtb) infection. Whereas, the contribution of IL17A in immunity to tuberculosis is usually accepted, the role of IL17F has been scarcely studied so far. The aim of this work was to evaluate the existence of a potential association of the non-synonymous variant rs763780 SNP of the IL17F gene with human tuberculosis. Accordingly, by comparing healthy donors (HD) and tuberculosis patients (TB) populations we demonstrated an association between the C allele of the SNP and the susceptibility to tuberculosis disease in Argentina. Furthermore, we found that peripheral blood mononuclear cells (PBMCs) from individuals with a more effective immune response against Mtb secreted the highest levels of IL17F when stimulated with a lysate of Mtb (Mtb-Ag). Besides, we evidenced that Mtb-Ag-stimulated PBMCs from HD carrying the C variant of the SNP displayed the lowest IFNG secretion, proliferation index, and SLAM expression as compared to TT carriers. Moreover, Mtb-Ag-stimulated PBMCs from TB carrying the C allele produced the lowest levels of IFNG, the highest level of IL17A, and the minimum proliferation indexes as compared to TT TB, suggesting a relationship between the C allele and tuberculosis severity. In fact, TB carrying the C allele presented a more severe disease, with the highest bacilli burden in sputum. Together, our findings identify the IL17F rs763780 SNP as a biomarker of tuberculosis susceptibility and advanced disease severity in Argentina, suggesting that IL17F could be a critical cytokine in tuberculosis immunity.

Elevated levels of inflammatory markers in women with rheumatoid arthritis

Rheumatoid arthritis (RA) is an autoimmune and progressive disease. Evidence indicates that inflammatory mediators may contribute to the genesis and/or evolution of this clinical condition. Thus, the objective was to evaluate and compare the plasma levels of Interleukin-17 (IL-17), Tumor Necrosis Factor-Alpha (TNF-α) and Complement 3 (C3) in women with RA and healthy controls (HC), as well as to evaluate the association them with the disease activity. 25 women with RA and 15 HC were recruited. Plasma levels of biomarkers were measured by ELISA. All statistical analyzes were performed with a significance level set at α = 0.05. In the women with RA, the median age was 55 and, in the HC, was 50 years. The median value of DAS-28 was 3.79. The plasma levels of IL-17 (p = .03), TNF-α (p ≤ 0.01) and C3 (p ≤ 0.01) were higher in women with RA. The ROC curve showed that TNF- α has a higher discriminating ability than IL-17 and C3. DAS-28 score correlated significantly with C3 levels in women with RA (r = 0.91; p < .01). These findings reaffirm the participation of the immune system in pathophysiology of RA, suggest that TNF-α levels may be a good biomarker and that elevated C3 levels contribute to the worsening of the disease.

Elevated circulating IL-17 level is associated with inflammatory arthritis and disease activity: A meta-analysis

OBJECTIVES

Previous studies found that the interleukin (IL)-17 level was elevated in inflammatory arthritis, but results were inconsistent. This meta-analysis aimed to investigate the association of IL-17 cytokine with osteoarthritis (OA), rheumatoid arthritis (RA), ankylosing spondylitis (AS) and psoriatic arthritis (PsA).

METHODS

Relevant studies were searched using databases. Standardized mean difference (SMD) was calculated. Correlation coefficient was utilized to evaluate the relationship between IL-17 and disease activity of AS and RA. Subgroup analysis, sensitivity analysis and meta-regression were applied to explore the sources of heterogeneity.

RESULTS

83 records were enrolled. The IL-17 level was elevated in AS (SMD = 2.348, P < .001), RA (SMD = 1.502, P < .001), PsA (SMD = 1.710, P < .001) and OA (SMD = 1.192, P = .016), and similar results occurred in subgroup analysis. Furthermore, the IL-17 level was positively associated with disease activity of AS and RA.

CONCLUSION

Circulating IL-17 level is significantly elevated in inflammatory arthritis and is related to the disease activity of AS and RA, suggesting that it plays an important role in the pathogenesis and progression of inflammatory arthritis (especially in AS and RA).

Association of Interleukin-17F 7488A/G and 7383A/G Polymorphisms With Rheumatoid Arthritis: A Meta-Analysis

OBJECTIVES

This meta-analysis aims to summarize and estimate the relationship between rheumatoid arthritis (RA) susceptibility and two polymorphisms of interleukin-17F (IL-17F) 7488A/G and 7383A/G.

MATERIALS AND METHODS

PubMed, Embase and Web of Science were searched up to 01 July 2017. Case-control studies with genotype frequencies data for 7488A/G and 7383A/G were included. The pooled effects were calculated by fixed-effect model or random effects model.

RESULTS

A total of seven publications with 1,409 RA patients and 1,303 controls were included in the present meta-analysis. The results indicated that 7488A/G was significantly associated with increased susceptibility to RA (GA vs. AA: odds ratio [OR]=1.43, 95% confidence interval [CI]: 1.07-1.90, p=0.02; GG vs. AA: OR=3.22, 95% CI: 1.54-6.74, p=0.002; GA+GG vs. AA: OR=1.57, 95% CI: 1.02-2.42, p=0.04; GG vs. GA+AA: OR=3.05, 95% CI: 1.46-6.39, p=0.003). In subgroup analysis, 7488A/G was a strong risk factor in Europeans but not in Americans or Africans. No significant association was found between 7383A/G and RA in overall population or ethnic subgroups by all genetic model comparisons.

CONCLUSION

This meta-analysis provided evidence that IL-17F 7488A/G polymorphism is associated with increased RA susceptibility, while no clear correlation was found between 7383A/G and RA.

An Enrichment Strategy Yields Seven Novel Single Nucleotide Polymorphisms Associated With Mortality and Altered Th17 Responses Following Blunt Trauma

Trauma is the leading cause of death worldwide for individuals under the age of 55. Interpatient genomic differences, in the form of candidate single-nucleotide polymorphisms (SNPs), have been associated previously with adverse outcomes after trauma. However, the utility of these SNPs to predict outcomes based on a meaningful endpoint such as survival is as yet undefined. We hypothesized that specific SNP haplotypes could segregate trauma survivors from non-survivors. Genomic DNA samples were obtained from 453 blunt trauma patients, for whom complete daily clinical and biomarker data were available for 397. Of these, 13 patients were non-survivors and the remaining 384 were survivors. All 397 DNA samples were amplified, fragmented, and examined for 551,839 SNPs using the Illumina Infinium CoreExome-24 v1.1 BeadChip (Illumina). To enrich for likely important SNPs, we initially compared SNPs of the 13 non-survivors versus 13 matched survivors, who were matched algorithmically for injury severity score (ISS), age, and gender ratio. This initial enrichment yielded 126 SNPs; a further comparison to the haplotypes of the remaining 371 survivors yielded a final total of 7 SNPs that distinguished survivors from non-survivors. Furthermore, severely injured survivors with the same seven SNPs as non-survivor exhibited distinct inflammatory responses from similarly injured survivors without those SNPs, and specifically had evidence of altered Th17 cell phenotypes based on computational modeling. These studies suggest an interaction among genetic polymorphism, injury severity, and initial inflammatory responses in driving trauma outcomes.

Role of IL-6/RORC/IL-22 axis in driving Th17 pathway mediated immunopathogenesis of schizophrenia

The immuno-inflammatory origin of schizophrenia in a subset of patients is viewed as a key element of an overarching etiological construct. Despite substantial research, the immune components exerting major effect are yet to be fully clarified. Disrupted T cell networks have consistently been linked to the pathogenesis of schizophrenia. Amongst the Th cell subsets, the Th17 cells have emerged as a paradigmatic lineage with significant functional implications in a vast number of immune mediated diseases including brain disorders such as schizophrenia. The present study was aimed at examining the functional role of the Th17 pathway in schizophrenia. To address this, genotyping of IL17A (rs2275913; G197A) Single Nucleotide Polymorphism was carried out by the PCR-RFLP method in 221 schizophrenia patients and 223 healthy control subjects. Gene expression of two transcription factors STAT3 and RORC was quantified in a subset of drug naïve schizophrenia patients (n = 56) and healthy controls (n = 52) by TaqMan assay. The plasma levels of fifteen cytokines belonging to Th17 pathway were estimated in a subset of drug naïve schizophrenia patients (n = 61) and healthy controls (n = 50) by using Bio-Plex Pro Human Th17 cytokine assays. The AA genotype was associated with higher total score of bizarre behaviour and apathy in female schizophrenia patients. A high gene expression level of RORC was observed in drug naïve schizophrenia patients. In addition, significantly elevated plasma levels of IL-6 and IL-22, and reduced levels of IL-1β and IL-17F were noted in schizophrenia patients. Taken together, these findings indicate a dysregulated Th17 pathway in schizophrenia patients.

Interleukin-17A and -17F single nucleotide polymorphisms associate with susceptibility of asthma in Chinese Han population

Interleukin 17 (IL-17) plays important roles in the progression of asthma. Genetic variants in the Il-17 may influence the immunopathogenesis of many diseases. Many studies have investigated the relevance of IL-17 polymorphism with cancers or immune diseases, including asthma. In this study, single nucleotide polymorphisms (SNPs) of IL-17 were explored by PCR-RFLP and verified by sequencing method. The frequencies of genotypes and alleles were analyzed. Haplotypes were analyzed with the SHEsis online program. The relationship between the genotypes of SNPs and IgE level was also investigated. The False Discovery Rate (FDR) correction was performed (P-adjusted < 0.05). The frequencies of A allele, GA and (GA + AA) genotype of rs3748067 were significantly higher in asthma patients. As for rs763780, the C allele in patients was more frequent than healthy controls. In addition, we found C carriers (CT + CC) were significantly higher in asthma patients. We further found that the haplotype CT for IL-17F (rs763780/rs2397084) was associated with an increased susceptibility of asthma, but this association did not survive after FDR correction. The level of serum total IgE in mutant group (GA + AA) of rs3748067 was significantly higher than the wild genotype (GG) group and control group. These results suggested that IL-17 SNPs, but not haplotypes may be associated with the susceptibility of asthma in Chinese Han population from central China.

Involvement of the IL23/Th17 Pathway in the Pathogenesis of Tunisian Pemphigus Foliaceus

Pemphigus foliaceus (PF) is a rare autoimmune skin disease caused by anti-Dsg1 pathogenic autoantibodies. It is considered as a Th2-mediated disease. Likewise, Th17 cells were recently described in the pathogenesis of the disease but their role is still unclear. We aimed to unravel the eventual implication of the IL23/Th17 pathway in the development of PF. A case-control study was conducted on 115 PF patients and 201 healthy controls using PCR-RFLP and AS-PCR methods. SNPs in IL23R, RORγt, IL17A, IL17F, IL17AR, TNFa, and STAT3 genes were genotyped. mRNA expression of IL23R and RORγt was evaluated using Q-PCR. The frequency of circulating Th17 cells was analyzed by flow cytometry. Genetic associations between IL23R>rs11209026, IL17A>rs3748067, IL17F>rs763780, and TNFa>rs1800629 and the susceptibility to PF were reported. Moreover, we revealed a significant increased frequency of circulating CD4⁺IL17⁺ cells as well as higher mRNA levels of RORγt and IL23R in PBMCs of patients. However, no significant increase of RORγt and IL23R mRNA expression was observed in lesional skin biopsies. In spite of the little size of specimens, our results provide converging arguments for the contribution of the IL23/Th17 pathway in the pathogenesis of PF.

IL-17A, IL-17RC polymorphisms and IL17 plasma levels in Tunisian patients with rheumatoid arthritis

Background

Interleukin-17 (IL-17), a cytokine mainly secreted by Th17 cells, seems to play a significant role in the pathogenesis of rheumatoid arthritis (RA). Functional genetic polymorphisms in IL-17 and its receptor genes can influence either qualitatively or quantitatively their functions. Therefore, we aimed to study the impact of IL17-A and IL17RC polymorphisms on plasma level of IL-17 and RA susceptibility and severity.

Methods

In this context, IL-17A*rs2275913 and IL-17RC*rs708567 polymorphisms were investigated together with the quantification of IL17 plasma level in 115 RA patients and 91 healthy control subjects matched in age, sex and ethnic origin.

Results

There were no statistically significant associations between IL-17A and IL-17RC studied polymorphisms and RA susceptibility. In contrast, IL-17A plasma levels were significantly higher in patients (55.07 pg/ml) comparatively to controls (4.75 pg/ml), p<10E-12. A ROC curve was used to evaluate the performance of plasma IL-17 in detecting RA. Given 100% specificity, the highest sensitivity of plasma IL-17A was 61.7% at a cut-off value of 18.25 pg/ml; p < 10E-21, CI = [0.849–0.939]. Analytic results showed that the IgM-rheumatoid factor and anti-CCP antibodies were significantly less frequent in patients with the IL-17RC*A/A genotype than those carrying *G/G and *G/A genotypes; p = 0.013 and p = 0.015, respectively. Otherwise, IL-17 plasma levels’ analysis showed a significant association with the activity of RA (DAS28≥5.1 = 74.71 pg/ml vs. DAS28<5.1 = 11.96 pg/ml), p<10E-6.

Conclusion

IL-17A*rs2275913 (G/A) and IL-17RC*rs708567 (G/A) polymorphisms did not seem to influence RA susceptibility in Tunisian population. This result agrees with those reported previously. Plasma IL-17A level seems to be predictive of severe RA occurrence.

Role of gene polymorphisms/haplotypes and serum levels of interleukin-17A in susceptibility to viral myocarditis

Interleukin-17A (IL-17A) has been implicated in the pathogenesis of viral myocarditis (VMC). However, the role of IL-17A polymorphisms in susceptibility to VMC has not been reported to date. The aim of this study was to explore the association between IL-17A variants as well as serum IL-17 levels with VMC. Three single-nucleotide polymorphisms (SNPs) (rs2275913, rs3819025, and rs3748067) were analyzed by the polymerase chain reaction-restriction fragment length polymorphism method in 236 VMC patients and 259 controls from China. Serum IL-17A levels were measured by enzyme-linked immunosorbent assay kits. Multivariable logistic regression analysis that the rs2275913 AA genotype and the haplotype -197A/+45G/+1249G (AGG) were associated with an increased risk of VMC (all P < 0.05). Consistent with these findings, the rs2275913 AA genotype was linked to higher serum IL-17A compared to GG/AG genotype (all P < 0.001). We observed no associations between the other two SNPs and risk of VMC. Serum IL-17A levels were significantly higher in the VMC group than controls (P < 0.001) and gradually increased with the increase of New York Heart Association grade in VMC patients (P < 0.05). Spearman correlation test revealed that the serum IL-17A level was correlated with the cardiac damage and left ventricular systolic functions among VMC patients (all P < 0.05). Our study reveals that IL-17A expression may contribute to the development and severity of VMC. The SNP rs2275913 in the IL-17A gene might exert influence on susceptibility to VMC via linking with the serum IL-17A level.

Polymorphisms within Genes Involved in Regulation of the NF-κB Pathway in Patients with Rheumatoid Arthritis

Genes involved in regulation of the nuclear factor-κB (NF-κB)-pathway are suggested to play a role in pathogenesis of rheumatoid arthritis (RA). In the present study, genetic polymorphisms of TLR2, TLR4, TLR9 and NF-κB1 genes were investigated to assess their associations with RA susceptibility, progression and response to anti-TNF-α therapy. A group of 110 RA patients and 126 healthy individuals were genotyped for TLR2 (rs111200466), TLR4 (rs4986790, rs4986791), TLR9 (rs5743836, rs187084) and NF-κB1 (rs28362491) alleles. The presence of the TLR9 -1486 T variant (p < 0.0001) and its homozygosity (p < 0.0001) were found to be associated with disease susceptibility. The TLR9 -1237 C allele was associated with predisposition to RA in females only (p = 0.005). Moreover, the TLR4 rs4986791 G (rs4986790 T) alleles were more frequently detected among patients with the stage IV disease (p = 0.045), and were associated with more effective response to anti-TNF-α therapy (p = 0.012). More efficient response to anti-TNF-α treatment was also observed in patients with del within the NF-κB1 gene (p = 0.047), while for the TLR9 -1486 T homozygotes, the treatment was ineffective (p = 0.018). TLR polymorphisms affect disease susceptibility and response to therapy with TNF-α inhibitors in RA patients of Caucasian origin.