Influence of Promoter Polymorphisms of the TNF-α (-308G/A) and IL-6 (-174G/C) Genes on Therapeutic Response to Etanercept in Rheumatoid Arthritis

The Association between Genetics and Response to Treatment with Biologics in Patients with Psoriasis, Psoriatic Arthritis, Rheumatoid Arthritis, and Inflammatory Bowel Diseases: A Systematic Review and Meta-Analysis

Genetic biomarkers could potentially lower the risk of treatment failure in chronic inflammatory diseases (CID) like psoriasis, psoriatic arthritis (PsA), rheumatoid arthritis (RA), and inflammatory bowel disease (IBD). We performed a systematic review and meta-analysis assessing the association between single nucleotide polymorphisms (SNPs) and response to biologics. Odds ratio (OR) with 95% confidence interval (CI) meta-analyses were performed. In total, 185 studies examining 62,774 individuals were included. For the diseases combined, the minor allele of MYD88 (rs7744) was associated with good response to TNFi (OR: 1.24 [1.02-1.51], 6 studies, 3158 patients with psoriasis or RA) and the minor alleles of NLRP3 (rs4612666) (OR: 0.71 [0.58-0.87], 5 studies, 3819 patients with RA or IBD), TNF-308 (rs1800629) (OR: 0.71 [0.55-0.92], 25 studies, 4341 patients with psoriasis, RA, or IBD), FCGR3A (rs396991) (OR: 0.77 [0.65-0.93], 18 studies, 2562 patients with psoriasis, PsA, RA, or IBD), and TNF-238 (rs361525) (OR: 0.57 [0.34-0.96]), 7 studies, 818 patients with psoriasis, RA, or IBD) were associated with poor response to TNFi together or infliximab alone. Genetic variants in TNFα, NLRP3, MYD88, and FcRγ genes are associated with response to TNFi across several inflammatory diseases. Most other genetic variants associated with response were observed in a few studies, and further validation is needed.

The involvement of cytokine gene polymorphism in determining the vulnerability to Blastocystis and Helicobacter pylori co-infection in the Egyptian population

AIMS

The present study aimed to identify any potential association between IL-1β and TNF-α gene polymorphism and the risk of Blastocystis infection as well as co-infection of Blastocystis with Helicobacter pylori (H.pylori).

METHODOLOGY

A total of 314 stool samples were collected and examined microscopically for the detection of parasitic infection. DNA was extracted from all samples and utilized to identify Blastocystis molecularly. Positive samples were used for H. pylori detection by rapid tests and PCR. Moreover, we investigate polymorphism in the TNF-α gene at position -1031T/C, -308 G/A, and IL-1β at position +3954C/T using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay.

RESULTS

Out of the 314 stool samples, Blastocystis was detected in 93 (29.6 %); among them, 54 (58.1 %) had a mixed infection of Blastocystis with H. pylori. The TT genotype of the IL-1β gene at position +3954 was significantly higher in Blasocystis-infected patients than in uninfected patients (17.2% vs. 6.3 %, P = 0.02), which might be considered a risk factor (OR = 3.2; CI =1.21-8.52). The TNF-α at position -1031 TT genotype was significantly higher in Blastocystis-infected patients than uninfected patients (44.1% vs. 10.8 %, P< 0.0001). The T allele (OR= 2.67; CI=1.51-4.72, P = 0.0008) might be considered a risk factor. The TNF- α at position -308 AA genotype is higher in Blasocystis infected than uninfected (17.2% vs 7.2 %, P = 0.03). TNF-α -308 AA (OR = 2.72; CI = 1.08-6.89) and A allele (OR= 1.46; CI= 0.797-2.66) might be considered risk factors. The TNF- α at position -308 G/A showed that the GG is the most frequent genotype in Blastocystis with H. pylori-positive patients with a significant association (P = 0.004), as well as the G allele (P = 0.02). The G allele (OR=1.924; CI= 1.071-3.454) might be considered a risk factor for co-infection of Blastocystis and H. pylori.

CONCLUSION

SNPs (-1031 T/C and -308 G/A) of the TNF-α and (+3954 C/T) of the IL-1β may be a useful marker in the assessment of the risk of Blastocystis infection, and TNF-α at position -308 G/A) may be a predictor for co-infection of Blastocystis with H. pylori.

Harmonizing Medicine and Surgery in the Pursuit of Boolean Remission: A Rheumatological Magnum Opus

Rheumatic diseases encompass a diverse group of musculoskeletal conditions that often lead to inflammation, pain, and significant limitations in patients' lives. While traditional treatment approaches have primarily centered on medications to control symptoms, recent developments have introduced the concept of Boolean remission. Boolean remission offers a comprehensive evaluation of disease activity by considering clinical, biochemical, and patient-reported outcomes. This narrative review explores the multifaceted landscape of Boolean remission in the context of rheumatic diseases, with a focus on rheumatoid arthritis (RA), as it remains a substantial clinical challenge. The review outlines the definition, criteria, historical context, and development of Boolean remission, shedding light on its emergence as a more patient-centered and stringent treatment goal. The role of pharmacological interventions, including immunomodulators and biologics, in achieving Boolean remission is discussed, emphasizing the significance of treatment protocols that encompass regular monitoring, medication adjustment, shared decision-making, and patient education. Surgical interventions, such as joint replacements and synovectomies, complement medication-based strategies when joint damage becomes severe, with adherence to surgical protocols ensuring sustained Boolean remission. The integration of medicine and surgery through integrated care models and interdisciplinary teams is examined as a critical aspect of optimizing patient outcomes. Boolean remission's broader impact on healthcare policies and clinical trial endpoints is explored, underscoring its growing significance in rheumatic disease management. The review concludes by looking toward the future, where emerging technologies, biomarkers, and personalized medicine approaches hold promise in refining Boolean remission criteria and making it a more attainable and impactful treatment goal. Policy implications suggest the integration of Boolean remission into healthcare quality metrics, incentivizing healthcare providers to prioritize this rigorous standard of care. Boolean remission represents a pivotal shift in the holistic and patient-centered management of rheumatic diseases, offering hope for improved patient outcomes and enhanced quality of life in this challenging clinical landscape.

Can Pharmacogenetic Variants in TPMT, MTHFR and SLCO1B1 Genes Be Used as Potential Markers of Outcome Prediction in Systemic Sclerosis Patients?

Systemic sclerosis (SSc) is a rare connective tissue disorder with highest morbidity and mortality among rheumatologic diseases. Disease progression is highly heterogeneous between patients, implying a strong need for individualization of therapy. Four pharmacogenetic variants, namely TPMT rs1800460, TPMT rs1142345, MTHFR rs1801133 and SLCO1B1 rs4149056 were tested for association with severe disease outcomes in 102 patients with SSc from Serbia treated either with immunosuppressants azathioprine (AZA) and methotrexate (MTX) or with other types of medications. Genotyping was performed using PCR-RFLP and direct Sanger sequencing. R software was used for statistical analysis and development of polygenic risk score (PRS) model. Association was found between MTHFR rs1801133 and higher risk for elevated systolic pressure in all patients except those prescribed with MTX, and higher risk for kidney insufficiency in patients prescribed with other types of drugs. In patients treated with MTX, variant SLCO1B1 rs4149056 was protective against kidney insufficiency. For patients receiving MTX a trend was shown for having a higher PRS rank and elevated systolic pressure. Our results open a door wide for more extensive research on pharmacogenomics markers in patients with SSc. Altogether, pharmacogenomics markers could predict the outcome of patients with SSc and help in prevention of adverse drug reactions.

Prediction of response to anti-TNF treatment using laboratory biomarkers in patients with rheumatoid arthritis: a systematic review

OBJECTIVES

In this systematic review, we aim to identify laboratory biomarkers that predict response to tumour necrosis factor inhibitors (TNFi) in patients with rheumatoid arthritis (RA).

METHODS

EMBASE, PubMed and Cochrane Library (CENTRAL) were searched for studies that presented predictive accuracy measures of laboratory biomarkers, or in which these were calculable. Likelihood ratios were calculated in order to determine whether a test result relevantly changed the probability of response. Likelihood ratios between 2-10 and 0.5-0.1 were considered weak predictors, respectively, and ratios above 10 or below 0.1 were considered strong predictors of response. Primary focus was on biomarkers studied ≥3 times.

RESULTS

From 41 included studies, data on 99 different biomarkers were extracted. Five biomarkers were studied ≥3 times, being (1) anti-cyclic citrullinated peptide (CCP), (2) rheumatoid factor, (3) -308 polymorphism in the TNF-α gene, (4) SE copies in the HLA-DRB1 gene and (5) FcGR2A polymorphism. No studies showed a strong predictive association and only one study on anti-CCP showed a weak positive association.

CONCLUSIONS

No biomarkers were found that consistently showed a (strong) predictive effect for response to TNFi in patients with RA. Given the disappointing yield of previous predictive biomarker research, future studies should focus on exploring, combining and validating the most promising laboratory biomarkers identified in this review, and searching for new predictors. Besides this, they should focus on contexts where prediction-aided decision-making can have a large impact (even with limited predictive value of markers/models).

PROSPERO REGISTRATION NUMBER

CRD42021278987.

Associations between the interleukin-6 rs1800795 G/C and interleukin-6 receptor rs12083537 A/G polymorphisms and response to disease-modifying antirheumatic drugs in rheumatoid arthritis: A meta-analysis

OBJECTIVE

We aimed to investigate the association between interleukin-6 (IL-6) rs1800795 G/C, IL-6 receptor (IL-6R) rs12083537 A/G, and rs4329505 T/C polymorphisms and responsiveness to disease-modifying antirheumatic drugs (DMARDs) in patients with rheumatoid arthritis (RA).

METHODS

We searched Medline, Embase, and Web of Science databases. We conducted a meta-analysis of studies on the association between the IL-6 rs1800795 G/C, IL-6R rs12083537 A/G and rs4329505 T/C polymorphisms and responsiveness to DMARDs in RA patients.

RESULTS

Fourteen studies from eight published articles involving 982 patients were included in this meta-analysis. The meta-analysis showed a significant association between the IL-6 rs1800795 G allele and response to DMARDs in RA (P = 0.008). Stratification by DMARD class showed that the IL-6 rs1800795 G allele was significantly associated with responsiveness to biological DMARDs (bDMARDs) (P = 0.022), but not conventional synthetic DMARDs (P = 0.145). A significant association was also found between the IL-6 rs1800795 G/C polymorphism and response to DMARDs. The meta-analysis revealed a significant association between the IL-6R rs12083537 A allele and response to tocilizumab in RA patients (P = 0.001). A significant association was also found between the IL-6R rs12083537 AA genotype and response to tocilizumab in RA patients (P = 0.001). However, no association was found between the IL-6R rs4329505 T/C polymorphism and response to tocilizumab.

CONCLUSIONS

This meta-analysis revealed associations between treatment response to bDMARDs and the IL-6 rs1800795 G/C polymorphism, and between response to tocilizumab and the IL-6R rs12083537 A/G polymorphism in RA.

Gene Ontology Analysis Highlights Biological Processes Influencing Non-Response to Anti-TNF Therapy in Rheumatoid Arthritis

Anti-TNF therapy has significantly improved disease control in rheumatoid arthritis, but a fraction of rheumatoid arthritis patients do not respond to anti-TNF therapy or lose response over time. Moreover, the mechanisms underlying non-response to anti-TNF therapy remain largely unknown. To date, many single biomarkers of response to anti-TNF therapy have been published but they have not yet been analyzed as a system of interacting nodes. The aim of our study is to systematically elucidate the biological processes underlying non-response to anti-TNF therapy in rheumatoid arthritis using the gene ontologies of previously published predictive biomarkers. Gene networks were constructed based on published biomarkers and then enriched gene ontology terms were elucidated in subgroups using gene ontology software tools. Our results highlight the novel role of proteasome-mediated protein catabolic processes (p = 2.91 × 10⁻¹⁵) and plasma lipoproteins (p = 4.55 × 10⁻¹¹) in anti-TNF therapy response. The results of our gene ontology analysis help elucidate the biological processes underlying non-response to anti-TNF therapy in rheumatoid arthritis and encourage further study of the highlighted processes.

Characterizing Pharmacokinetics in Children With Obesity-Physiological, Drug, Patient, and Methodological Considerations

Childhood obesity is an alarming public health problem. The pediatric obesity rate has quadrupled in the past 30 years, and currently nearly 20% of United States children and 9% of children worldwide are classified as obese. Drug distribution and elimination processes, which determine drug exposure (and thus dosing), can vary significantly between patients with and without obesity. Obesity-related physiological changes, such as increased tissue volume and perfusion, altered blood protein concentrations, and tissue composition can greatly affect a drug's volume of distribution, which might necessitate adjustment in loading doses. Obesity-related changes in the drug eliminating organs, such as altered enzyme activity in the liver and glomerular filtration rate, can affect the rate of drug elimination, which may warrant an adjustment in the maintenance dosing rate. Although weight-based dosing (i.e., in mg/kg) is commonly practiced in pediatrics, choice of the right body size metric (e.g., total body weight, lean body weight, body surface area, etc.) for dosing children with obesity still remains a question. To address this gap, the interplay between obesity-related physiological changes (e.g., altered organ size, composition, and function), and drug-specific properties (e.g., lipophilicity and elimination pathway) needs to be characterized in a quantitative framework. Additionally, methodological considerations, such as adequate sample size and optimal sampling scheme, should also be considered to ensure accurate and precise top-down covariate selection, particularly when designing opportunistic studies in pediatric drug development. Further factors affecting dosing, including existing dosing recommendations, target therapeutic ranges, dose capping, and formulations constraints, are also important to consider when undergoing dose selection for children with obesity. Opportunities to bridge the dosing knowledge gap in children with obesity include modeling and simulating techniques (i.e., population pharmacokinetic and physiologically-based pharmacokinetic [PBPK] modeling), opportunistic clinical data, and real world data. In this review, key considerations related to physiology, drug parameters, patient factors, and methodology that need to be accounted for while studying the influence of obesity on pharmacokinetics in children are highlighted and discussed. Future studies will need to leverage these modeling opportunities to better describe drug exposure in children with obesity as the childhood obesity epidemic continues.

Toward Overcoming Treatment Failure in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disorder characterized by inflammation and bone erosion. The exact mechanism of RA is still unknown, but various immune cytokines, signaling pathways and effector cells are involved. Disease-modifying antirheumatic drugs (DMARDs) are commonly used in RA treatment and classified into different categories. Nevertheless, RA treatment is based on a "trial-and-error" approach, and a substantial proportion of patients show failed therapy for each DMARD. Over the past decades, great efforts have been made to overcome treatment failure, including identification of biomarkers, exploration of the reasons for loss of efficacy, development of sequential or combinational DMARDs strategies and approval of new DMARDs. Here, we summarize these efforts, which would provide valuable insights for accurate RA clinical medication. While gratifying, researchers realize that these efforts are still far from enough to recommend specific DMARDs for individual patients. Precision medicine is an emerging medical model that proposes a highly individualized and tailored approach for disease management. In this review, we also discuss the potential of precision medicine for overcoming RA treatment failure, with the introduction of various cutting-edge technologies and big data.

Exploring pharmacogenetic variants for predicting response to anti-TNF therapy in autoimmune diseases: a meta-analysis

Aim: The aim of this study is to explore how SNPs may affect the response to anti-TNF-α therapy in the major autoimmune diseases, such as psoriasis, rheumatoid arthritis, inflammatory bowel diseases and Spondyloarthritis. Methodology: We conducted a systematic overview on the field, by assessing all studies that examined the association between polymorphisms and response to anti-TNF-α therapy in participants of European descent. Results: In total, six independent SNPs located in FCGR2A, FCGR3A, TNF-α and TNFRSF1B genes were significantly associated with response to TNF-α blockers, found mainly in disease-subgroup analyses. Conclusion: No common pharmacogenetic variant was identified for all autoimmune diseases under study, suggesting the requirement of more studies in the field in order to capture such predictive variants that will aid treatment selection.

IL6 genetic variants haplotype is associated with susceptibility and disease activity but not with therapy response in patients with inflammatory bowel disease

PURPOSE

The aim of the present study was to evaluate the IL6 -174 G>C (rs1800795) and -572 G>C (rs1800796) genetic variants and their association with inflammatory bowel diseases (IBDs), disease activity, and response to TNF-α inhibitors.

METHODS

The study included 178 patients with IBD and 224 healthy controls. Among the IBD patients, 66 of them were in use of TNF-α inhibitors therapy and were followed during 48 weeks and categorized as responders and non-responders.

RESULTS

In total, 89 (50.0%) had ulcerative colitis (UC) and 89 (50.0%) had Crohn's disease (CD). The IL6 -572 CC genotype presented a protective effect in CD patients in codominant and recessive models, while the IL6 -174 CC genotype was associated with susceptibility to UC and CD. The presence of G/C haplotype in the recessive model (GCGC) was associated with UC. The Crohn's disease endoscopic index of severity was low in those patients carrying the GCGC haplotype. It was observed that there was no association between the IL6 genetic variants and TNF-α inhibitor therapy response.

CONCLUSION

The G/C haplotype (recessive model) was associated with susceptibility to UC but not to CD. However, the G/C haplotype (dominant model) was associated with the endoscopic activity of CD. Moreover, these IL6 variants did not predict the TNF-α inhibitor therapy response.

Relationship Between Interleukin-6 -174G/C Genetic Variant and Efficacy of Methotrexate Treatment in Psoriatic Arthritis Patients

Introduction

The purpose of the study was to investigate whether single-nucleotide polymorphisms (SNPs) IL-6 −174 G/C and IL-6R Asp358Ala are associated with susceptibility to psoriatic arthritis (PsA) or affect response to treatment with methotrexate (MTX).

Patients and Methods

Seventy-four patients diagnosed with PsA and qualified for MTX treatment were enrolled to the study. The control group consisted of 120 healthy individuals. Polymorphisms IL-6 −174 G/C and IL-6R Asp358Ala were genotyped using a polymerase chain reaction (PCR) amplification employing LightSNiP assays.

Results

A significant association between the IL-6 −174 CC genotype and an improved clinical outcome of MTX therapy was observed. A good response was more frequently observed among PsA patients bearing the IL-6 −174 CC genotype than patients with the GC or GG genotypes (P = 0.007). On the other hand, patients carrying the IL-6 −174 GC genotype less frequently responded to MTX treatment as compared to patients with other genotypes (P = 0.006). With respect to the IL-6R Asp358Ala SNP, there were no significant differences in genotype and allelic frequencies in relation to clinical outcome of MTX treatment. No association was found between the IL-6 −174 G/C or IL-6R Asp358Ala SNPs and PsA susceptibility.

Conclusion

Results from this study provide evidence that the IL-6 −174 G/C polymorphism might influence efficacy of MTX treatment.

Usefulness of Cytokine Gene Polymorphisms for the Therapeutic Choice in Japanese Patients with Rheumatoid Arthritis

Background

Rheumatoid arthritis (RA) is characterized by systemic synovitis with bone erosion and joint cartilage degradation. Although the analysis of polymorphisms in cytokine-encoding genes is important or understanding the pathophysiology of RA and selecting appropriate treatment for it, few studies have examined such single-nucleotide polymorphisms (SNPs) specifically in Japanese patients. This study was established to investigate the associations between polymorphisms in cytokine-encoding genes, autoantibodies and therapeutic responses in Japanese RA patients.

Methods

The subjects in this study consisted of 100 RA patients and 50 healthy controls. We extracted data on sex, age, disease duration, rheumatoid factor (RF), anti-cyclic citrullinated peptide (anti-CCP) antibody, and therapeutic responses, including to methotrexate (MTX) and biological disease-modifying antirheumatic drugs (DMARDs). Genomic DNA was isolated from peripheral blood, which was genotyped for IL-10, TNF-α, TGF-β₁, and IFN-γ polymorphisms.

Results

Regarding IL-10 (−592 C/A and −819 C/T), significant decreases in the frequencies of the IL-10 (−592) CC genotype and (−819) CC genotype were found in RA patients compared with the levels in controls. For IFN-γ (+874 T/A), a significant decrease in the frequency of the TT genotype was found in RA patients compared with that in controls. Regarding TGF-β₁ (+869 T/C), patients with positivity for anti-CCP antibody had a significantly lower frequency of the CC genotype than those with negativity for it. Furthermore, the IL-10 (−592) CC genotype and (−819) CC genotype might be related to the biological DMARD-response.

Conclusion

Our results suggest that the analysis of polymorphisms in cytokine-encoding genes may be useful when selecting treatment for Japanese RA patients.

Polymorphisms Involved in Response to Biological Agents Used in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a systemic disease that leads to joint destruction. During the last decade, the therapy of RA has been principally based on biological drugs. Although the efficacy of biological therapy has been established, patients demonstrated a high heterogeneity in clinical response to treatment. Several genetic polymorphisms play a part in the different response to biological drugs. This review summarizes the pharmacogenetics of biological agents approved for clinical RA treatment. We reviewed PubMed papers published over the past 20 years (2000-2020), inserting as the search term "rheumatoid arthritis and polymorphisms". Despite some studies showing important correlations between genetic polymorphisms and response to biological therapy in RA patients, most of these findings are still lacking and inconsistent. The personalized treatment according to a pharmacogenetics approach is promising but the available pharmacogenetics data on biological treatment in RA are not adequate and reliable to recommend pharmacogenetic tests before starting biological therapy in RA patients.

Pharmacogenetics: A strategy for personalized medicine for autoimmune diseases

For many years, a considerable number of patients with autoimmune diseases (ADs) have suffered from a lack of drug response and drug-related toxicity. Despite the emergence of new therapeutic options such as biological agents, patients continue to struggle with these problems. Unfortunately, new challenges, including the paradoxical effects of biological drugs, have complicated the situation. In recent decades, efforts have been made to predict drug response as well as drug-related side effects. Thanks to the many advances in genetics, evaluation of markers to predict drug response/toxicity before the initiation of treatment may be an avenue toward personalizing treatments. Implementing pharmacogenetics and pharmacogenomics in the clinic could improve clinical care; however, obstacles remain to effective personalized medicine for ADs. The present study attempted to clarify the concept of pharmacogenetics/pharmacogenomics for ADs. After an overview on the pathogenesis of the most common types of treatments, this paper focuses on pharmacogenetic studies related to the selected ADs. Bridging the gap between pharmacogenetics and personalized medicine is also discussed. Moreover, the advantages, disadvantages and recommendations related to making personalized medicine practical for ADs have been addressed.

Interleukin 6 gene polymorphism is associated with protein serum level and disease activity in Polish patients with rheumatoid arthritis

Interleukin 6 (IL-6) is a pro-inflammatory cytokine involved in the development of rheumatoid arthritis (RA). The present study aimed to determine the possible association of the IL6 (rs1800795, G > C) polymorphism with RA susceptibility, disease progression and protein serum levels. Distribution of IL6 alleles and genotypes was similar in RA patients and controls. As expected, patients before induction of anti-tumour necrosis factor agents had significantly higher IL-6 levels as compared with controls (P = 0.002). The CC homozygous patients were characterised with the highest average concentrations of this pro-inflammatory cytokine before treatment (P = 0.028), and they also more frequently presented with more active disease (P = 0.048). These results imply that the IL6 rs1800795 CC homozygosity may play a rather unfavourable role in RA.

Susceptibility to Ulcerative Colitis and Genetic Polymorphisms of A251G SOD1 and C-262T CAT

BACKGROUND

Reactive oxygen species can attack and damage almost every molecule found in living cells, including proteins, carbohydrates, lipids, and DNA. For this reason, their production is normally tightly controlled. Among the most important defenses against these radicals are the superoxide dismutase (SOD) enzymes and catalase (CAT). Increasing attention has been given to the role of reactive oxygen metabolites in the pathogenesis of ulcerative colitis (UC), which is defined as an idiopathic and chronic intestinal inflammation. Accordingly, we hypothesized a relation between genetic polymorphisms in the two antioxidant enzymes SOD1 A251G (rs2070424) and CAT C-262T (rs1001179) and the risk of UC.

METHODS

The present case-control study included 109 UC patients (46 males and 50 females) and 186 (67 males and 119 females) gender-matched healthy controls. Genotyping was done by the PCR-RFLP method.

RESULTS

After adjusting for age and gender, a significant association was observed between the AG+GG genotypes of SOD1 A251G polymorphism (vs. AA genotype) and risk of UC (OR=0.29, 95% CI: 0.10-0.86, P= 0.025) after adjusting for age and gender. Our statistical analysis revealed that the CAT C-262T polymorphism did not associate with the risk of UC before and/or after adjusting for age and gender.

CONCLUSIONS

Based on the present statistical analysis, the G allele of the SOD1 A251G polymorphism decreases the risk of UC, thus it might be assumed that the G allele has a protective role.

NLRP3 and CARD8 Polymorphisms Influence Higher Disease Activity in Rheumatoid Arthritis

Background

The activation of NLRP3-inflammasome may contribute to inflammatory processes in rheumatoid arthritis (RA). Functional polymorphisms in the genes coding for its components NLRP3 and CARD8 were associated with a proinflammatory phenotype. Our aim was to investigate the influence of these polymorphisms on RA susceptibility and disease activity at the time of diagnosis and after six months of treatment.

Methods

A group of 128 RA patients treated with methotrexate and 122 healthy controls were genotyped for NLRP3 rs35829419 (p. Q705K) and CARD8 rs2043211 (p. C10X) polymorphisms.

Results

RA susceptibility was not influenced by the investigated polymorphisms or their interaction. The investigated polymorphisms explained 8% of variability in DAS28 at the time of diagnosis. Carriers of NLRP3 rs35829419 or CARD8 rs2043211 polymorphisms had significantly higher DAS28 at the time of diagnosis (p=0.003; p=0.022; respectively). Polymorphic CARD8 rs2043211 TT genotype was also associated with higher DAS28 after six months of treatment (p=0.033).

Conclusions

Genetic variability of inflammasome components may contribute to higher disease activity at the time of diagnosis and after 6 months of methotrexate treatment in RA patients. Better understanding of the immunological mechanisms behind a more active course of RA may suggest novel treatment approaches in a subset of patients with a proinflammatory phenotype.