IL-1B and IL-1Ra gene polymorphisms and disease severity in rheumatoid arthritis: interaction with their plasma levels

Inflammatory mediators, oxidative stress and genetic disturbance in rheumatoid arthritis rats supported by alfalfa seeds metabolomic constituents via blocking interleukin-1receptor

Rheumatoid arthritis (RA) is an autoimmune disease characterized by aggressive cartilage and bone erosion. This work aimed to evaluate the metabolomic profile of Medicago sativa L. (MS) (alfalfa) seeds and explore its therapeutic impact against RA in rats. Arthritis was induced by complete Freund's adjuvant (CFA) and its severity was assessed by the arthritis index. Treatment with MS seeds butanol fraction and interlukin-1 receptor antagonist (IL-1RA) were evaluated through measuring interlukin-1 receptor (IL-1R) type 1 gene expression, interlukin-1 beta (IL-1β), oxidative stress markers, C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α), prostaglandin E2 (PGE2), caspase-3 (Cas-3), intracellular adhesion molecule-1 (ICAM-1), DNA fragmentation, and chromosomal damage. Total phenolics/ flavonoids content in the ethyl acetate, butanol fraction and crude extract of MS seeds were estimated. The major identified compounds were Quercetin, Trans-taxifolin, Gallic acid, 7,4'-Dihydroxyflavone, Cinnamic acid, Kudzusaponin SA4, Isorhamnetin 3-O-beta-D-2'',3'',4''-triacetylglucopyranoside, Apigenin, 5,7,4'-Trihydroxy-3'-methoxyflavone, Desmethylxanthohumol, Pantothenic acid, Soyasapogenol E, Malvidin, Helilandin B, Stigmasterol, and Wairol. Treatment with MS seeds butanol fraction and IL-1RA enhanced all the biochemical parameters and the histopathological features of the ankle joint. In conclusion, Trans-taxifolin was isolated for the first time from the genus Medicago. MS butanol fraction seeds extract and IL-1 RA were considered as anti-rheumatic agents.

Smoking, Serum Albumin and 25-hydroxy Vitamin D Levels, and Bone Mineral Density Are Associated with Tooth Loss in Patients with Rheumatoid Arthritis

Objectives This study investigated factors associated with tooth loss in patients with rheumatoid arthritis (RA). Methods A total of 429 patients with RA were enrolled in the study. We examined tooth loss and clinical data. Patients were classified into two groups: a group with tooth loss (tooth loss-positive group), and a group without tooth loss (tooth loss-negative group). Patients were included in the tooth loss-positive group if they had fewer remaining teeth than the number defined by the Ministry of Health, Labour and Welfare in Japan to be the normal number teeth for that age and sex. Factors associated with tooth loss were analyzed by comparing the tooth loss-positive and loss-negative groups. Results The frequency of patients with tooth loss was 39.6%. The factors associated with tooth loss were smoking [odds ratio (OR) 1.638; 95% confidence interval (CI) 1.165-2.302], serum levels of albumin (OR 0.325; 95% CI 0.149-0.707) and 25-hydroxy vitamin D (OR 0.947; 95% CI 0.915-0.980), and total hip T score (OR 0.713; 95% CI 0.535-0.950). Conclusion This study revealed that tooth loss is associated with smoking, serum levels of albumin and 25-hydroxy vitamin D, and the total hip T score in patients with RA. Our findings may help prevent tooth loss in patients with RA.

IL-1 β gene (+3954 C/T, exon 5, rs1143634) and NOS2 (exon 22) polymorphisms associate with early aseptic loosening of arthroplasties

Aseptic prosthetic loosening (APL) and prosthetic joint infections (PJI) are frequent complications of hip and knee implants. Polymorphisms of cytokines and nitric oxide (NO), key inflammatory molecules in APL and PJI pathogenesis, could explain individual susceptibility to these complications. Three cytokines (IL-1-a, IL-1-β, TNF-α) and two nitric oxide synthase (NOS2, NOS3) genes polymorphisms were genotyped in 77 APL and 117 PJI patients and 145 controls with aseptic hip or knee implants that were implanted for > 16 years. Plasma cytokines and nitrate-nitrite (NOx) levels also were measured. The TT genotype and T allele of (+3954 C/T, exon 5, rs1143634) IL-1β polymorphism were more frequent in APL patients compared to controls (P = 0.03 and P = 0.02, respectively). No genotypic associations in PJI patients were observed. Plasma IL-6, TNF-α and NOx were significantly different between APL and controls (P < 0.0001). Plasma IL-1β and IL-6 were significantly higher in APL T allele carriers vs. non-carriers (P < 0.03). Knee implant (HR 2.488, 95% CI 1.307-4.739, P = 0.005), male gender (HR 2.252, 95% CI 1.121-4.525, P = 0.023), carriages of the TT genotype of the (+3954 C/T) IL-1β polymorphism (HR 3.704, 95% CI 1.274-10.753, P = 0.016) and AA genotype of the (exon 22) NOS2 polymorphism (HR 3.509, 95% CI 1.266-9.709, P = 0.016) were independently associated with a shorter implant survival by Cox regression. No genotypic associations in PJI patients were observed. Genotyping of IL-1β (+3954 C/T, exon 5, rs1143634) and NOS2 (exon 22) polymorphisms could be useful as predictors of early hip or knee APL.

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.

Genetic polymorphisms of ACE I/D, IL-1β G > A and IL-4 VNTR among Egyptian subjects with rheumatoid arthritis

BACKGROUND

Various reports examined the contribution of ACE I/D, IL-1β G > A and IL-4 VNTR with the susceptibility to RA but with conflicting findings. The goal of this study is to assess the impact of these three variants with the susceptibility, clinical and biochemical markers in addition to different composite indices of RA.

SUBJECTS AND METHODS

This case-control survey enclosed 120 RA Egyptian patients who were emulated with 150 healthy controls from the same territory. Their genomic DNA was genotyped utilising the PCR approach.

RESULTS

RA patients with ACE allele (D) and IL-4 VNTR allele (2 R) were expressively higher emulated with healthy controls (p < .05). Nevertheless, RA patients with IL-1β (A allele) failed to achieve an apparent significant emulated with healthy controls (p > .05).

CONCLUSIONS

This work specifies a noteworthy association for ACE I/D and IL-4 VNTR but not IL-1β G > A polymorphisms with RA susceptibility among Egyptian subjects.

Systems model identifies baseline cytokine concentrations as potential predictors of rheumatoid arthritis inflammatory response to biologics

BACKGROUND AND PURPOSE

Circulating cytokines are central pathological mediators of inflammatory autoimmune diseases like rheumatoid arthritis (RA). Immunological diversity in patients might contribute to inadequate responses to biological drugs. To address this therapeutic challenge, we developed a mathematical model that simultaneously describes temporal patterns of drug disposition for several biologics and their corresponding targeted cytokines, which were linked to triggering inflammatory responses.

EXPERIMENTAL APPROACH

A modeling framework was applied to RA-relevant cytokines regulating C-reactive protein (CRP) as an inflammatory marker. Clinical data were extracted from the literature for anakinra, canakinumab, infliximab, secukinumab, and tocilizumab, along with their corresponding cytokines: interleukin-1 receptor antagonist, IL-1β, tumor necrosis factor α (TNFα), IL-17A, and IL-6 receptor (IL-6R). Based on prior knowledge of regulatory mechanisms, cytokines were integrated with CRP profiles.

KEY RESULTS

The model well captured all serum concentration-time profiles of cytokines and CRP ratios to respective baselines following drug treatment with good precision. On external validation, reasonable model-performance on CRP dynamics, including rebound effects, was confirmed with clinical data not used in model development. Model-based simulations demonstrated that serum infliximab concentrations were accurately recapitulated in both a dose- and baseline TNFα-dependent manner. Furthermore, high baseline profiles of both IL-1β and/or targeted cytokines could be predictors of poor responses to biologics targeting TNFα and IL-6R, although the impact of IL-1β must be carefully interpreted.

CONCLUSIONS AND IMPLICATION

Our model provides a quantitative platform to guide targeting and dosing strategies, including combination and/or sequential therapy, according to distinct baseline cytokine patterns in RA patients.

Cytokines and chemokines multiplex analysis in patients with low disease activity rheumatoid arthritis

Rheumatoid arthritis is a severe chronic autoimmune disorder that results from pathological activation of immune cells and altered cytokine/chemokine network. The aim of our study was to evaluate concentrations of chosen cytokines and chemokines in blood sera and synovial fluid samples isolated from low disease activity rheumatoid arthritis (RA) patients and osteoarthritis (OA) sufferers. Blood sera and synovial fluid samples have been obtained from 24 OA and 14 RA patients. Cytokines/chemokines levels have been determined using a Milliplex^® Map 38-plex human cytokine/chemokine magnetic bead-based panel (Merck Millipore, Germany) and Luminex^® MAGPIX^® platform (Luminex USA). Low disease activity RA patients showed altered concentration of numerous cytokine/chemokine when compared to OA controls—they were characterized by, inter alia, increased: eotaxin/CCL11 (p = 0.037), GRO/CXCL1 (p = 0.037), IL-2 (p = 0.013), IL-4 (p = 0.017), IL-7 (p = 0.003), IL-8 (p = 0.0007) and GM-CSF (p = 0.037) serum levels, whilst MDC/CCL22 concentration was decreased in this group (p = 0.034). Eotaxin/CCL11 (p = 0.001), GRO/CXCL1 (p = 0.041), IL-10 (p = 0.003), GM-CSF (p = 0.01), IL-1RA (p = 0.0005) and VEGF (p = 0.01) concentrations in synovial fluid of RA females were also increased. Even with low disease activity score, RA patients exhibited increased concentrations of cytokines with pro- and anti-inflammatory activities, as well as numerous chemokines, growth factors and regulators of angiogenesis. Surprisingly, RA subjects also shown decreased concentration of CCL22 chemokine. The attempt to restore cytokine balance and tolerogenic environment is ineffective in RA sufferers even with good disease management. Distinguished factors could serve as possible indicators of disease progression even in low disease activity patients.

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.

Improving dexamethasone drug loading and efficacy in treating arthritis through a lipophilic prodrug entrapped into PLGA-PEG nanoparticles

Targeted delivery of dexamethasone to inflamed tissues using nanoparticles is much-needed to improve its efficacy while reducing side effects. To drastically improve dexamethasone loading and prevent burst release once injected intravenously, a lipophilic prodrug dexamethasone palmitate (DXP) was encapsulated into poly(DL-lactide-co-glycolide)-polyethylene glycol (PLGA-PEG) nanoparticles (NPs). DXP-loaded PLGA-PEG NPs (DXP-NPs) of about 150 nm with a drug loading as high as 7.5% exhibited low hemolytic profile and cytotoxicity. DXP-NPs were able to inhibit the LPS-induced release of inflammatory cytokines in macrophages. After an intravenous injection to mice, dexamethasone (DXM) pharmacokinetic profile was also significantly improved. The concentration of DXM in the plasma of healthy mice remained high up to 18 h, much longer than the commercial soluble drug dexamethasone phosphate (DSP). Biodistribution studies showed lower DXM concentrations in the liver, kidneys, and lungs when DXP-NPs were administered as compared with the soluble drug. Histology analysis revealed an improvement in the knee structure and reduction of cell infiltration in animals treated with the encapsulated DXP compared with the soluble DSP or non-treated animals. In summary, the encapsulation of a lipidic prodrug of dexamethasone into PLGA-PEG NPs appears as a promising strategy to improve the pharmacological profile and reduce joint inflammation in a murine model of rheumatoid arthritis.

Interleukin -1β Promotes Lung Adenocarcinoma Growth and Invasion Through Promoting Glycolysis via p38 Pathway

Background

There is a close relationship among inflammation, glycolysis, and tumors. The IL-1 family includes important inflammatory cytokines, among which IL-1β has been widely studied. In this study, we focused on the effect of IL-1β on glycolysis of lung adenocarcinoma (LUAD) cells in vivo and in vitro and explored its possible mechanisms.

Methods

A bioinformatic database and quantitative real-time PCR were used to analyze the expression of glycolysis-related enzyme genes and their correlations with IL1β in human LUAD samples. The human LUAD cell line A549 and Lewis lung carcinoma LLC cell line were stimulated with IL-1β. In vitro treatment effects, including glycolysis level, migration, and invasion were evaluated with a glucose assay kit, lactate assay kit, Western blotting, wound healing, and the transwell method. We established a mouse model of subcutaneous tumors using LLC cells pretreated with IL-1β and analyzed in vivo treatment effects through positron-emission tomography-computed tomography and staining. Virtual screening and molecular dynamic simulation were used to screen potential inhibitors of IL-1β.

Results

Our results showed that IL1β was positively correlated with the expression of glycolysis-related enzyme genes in LUAD. Glycolysis, migration, and invasion significantly increased in A549 and LLC stimulated with IL-1β. In vivo, IL-1β increased growth, mean standard uptake value, and pulmonary tumor metastasis, which were inhibited by the glycolysis inhibitor 2-deoxy-D-glucose and p38-pathway inhibitors. Small molecular compound ZINC14610053 was suggested being a potential inhibitor of IL-1β.

Conclusion

IL-1β promotes glycolysis of LUAD cells through p38 signaling, further enhancing tumor-cell migration and invasion. These results show that IL-1β links inflammation to glycolysis in LUAD, and targeting IL-1β and the glycolysis pathway may be a potential therapeutic strategy for lung cancer.

Association between Interleukin-1 Polymorphisms and Susceptibility to Dental Peri-Implant Disease: A Meta-Analysis

Background and objective: Interleukins (ILs), as important biochemical mediators, control the host response to inflammation and are associated with bone resorption. In the present meta-analysis, we investigated the association between IL−1 polymorphisms and susceptibility to dental peri-implant disease (PID). Materials and methods: We searched Web of Science, Cochrane Library, Scopus, and PubMed/Medline databases for studies published until 9 September2021, without any restrictions. We calculated the crude OR and 95% confidence intervals (CI) to estimate the associations between IL−1 polymorphisms and PID risk in the five genetic models. We further performed the subgroup analysis, sensitivity analysis, meta-regression, trial sequential analysis, and calculated the publication bias. Results: Out of 212 retrieved records, sixteen articles were used in the meta-analysis. There was no association between IL−1A (–889), IL−1B (−511), IL−1B (+3953), and IL−1RN (VNTR) polymorphisms and the risk of dental PIDs, but there was an increased risk of IL−1B (+3954) in the patients with PIDs. In addition, an association of the composite genotype of IL−1A (−889)/IL−1B (+3953) was observed with the risk of PIDs, but not for the composite genotype of IL−1A (−889)/IL−1B (+3954). The publication year, the ethnicity, sample size, and the outcome were significantly influenced pooled estimates of some genetic models. Trial sequential analysis showed the lack of sufficient sample sizes in the studies. Conclusions: Among IL−1 polymorphisms evaluated in the meta-analysis, the composite genotype of IL−1A (−889)/IL−1B (+3953) and IL−1B (+3954) were the only polymorphisms associated with the risk of PID. The T allele and CT genotype of IL−1B (+3954) polymorphism were also associated with an elevated risk of PID.

Bioactive compounds and therapeutic role of Brassica oleracea L. seeds in rheumatoid arthritis rats via regulating inflammatory signalling pathways and antagonizing interleukin-1 receptor action

CONTEXT

Rheumatoid arthritis (RA) is a chronic, progressive autoimmune disease characterized by aggressive and systematic polyarthritis.

OBJECTIVE

The present study aimed to isolate and identify the phenolic constituents in Brassica oleracea L. (Brassicaceae) seeds methanolic extract and evaluates its effect against rheumatoid arthritis in rats referring to the new therapy; interleukin-1 receptor antagonist (IL-1RA).

MATERIALS AND METHODS

The GC/MS profiling of the plant was determined. Arthritis induction was done using complete Freund's adjuvant. Arthritis severity was assessed by percentage of edema and arthritis index. IL-1 receptor type I gene expression, interleukin-1β (IL-1β), oxidative stress markers, protein content, inflammatory mediators, prostaglandin-E2 (PGE2), genetic abnormalities and the histopathological features of ankle joint were evaluated.

RESULTS

For the first time twelve phenolic compounds had been isolated from the seeds extract. Treatment with extract and IL-1RA improved the tested parameters by variable degrees.

CONCLUSIONS

RA is an irreversible disease, where its severity increases with the time of induction. Brassica oleracea L. seeds extract is considered as a promising anti-arthritis agent. IL-1 RA may be considered as an unusual therapeutic agent for RA disease. More studies are needed to consider the seeds extract as a nutraceutical agent and to recommend IL-1RA as a new RA drug.

Association of IL-1Ra Ser133Ser Variant with Susceptibility to Immune-Mediated and Inflammatory Diseases: A Meta-Analysis of 2622 Cases and 3854 Controls

Background:

The rs315952 (Ser133Ser) has been reported to influence the risk for immune-mediated as well as inflammatory diseases in many studies; however, the results remain inconsistent. The current meta-analysis was performed to give a more precise estimation for the relationship between this IL-1Ra missense variant and the risk of both types of diseases.

Methods:

Relevant publications were retrieved through a literature search in Web of Science, Medline, PubMed, Scopus, EMBASE, and Google scholar search engines, between 2000 and 2019. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess the strength of the association.

Results:

Twenty-two studies, including 2622 cases with and 3854 controls were identified. The IL-1Ra Ser133Ser variant does not confer an increased overall risk for immune-mediated and inflammatory diseases. This variant was statistically associated with decreased risk of systemic lupus erythematosus (under allelic, codominant heterozygous, and dominant models) or ankylosing spondylitis (in allelic and recessive models)(OR<1). Moreover, alleles, as well as genotypes of the IL-1Ra Ser133Ser variant, may confer an increased risk of immune-mediated and inflammatory diseases in Hispanics. However, this variant was not associated with susceptibility to immune-mediated and inflammatory diseases in both Asians and Arabs.

Conclusion:

The pooled results fail to support the hypothesis that the IL-1Ra Ser133Ser variant is associated with the overall risk of immune-mediated and inflammatory diseases. Performing large scale replication and meta-analysis of functional variants within this gene is encouraged to further investigate the influence of IL-1Ra SNPs on overall disease susceptibility.

Associations between Polymorphisms in the IL-1 Gene and the Risk of Rheumatoid Arthritis and Systemic Lupus Erythematosus: Evidence from a Meta-Analysis

BACKGROUND

Previous studies on polymorphisms in interleukin-1 (IL-1) and the risk of rheumatoid arthritis (RA)/systemic lupus erythematosus (SLE) yielded inconsistent results.

OBJECTIVES

The authors performed this meta-analysis to more robustly evaluate associations between polymorphisms in the IL-1 gene and the risk of RA/SLE.

METHODS

MEDLINE, Embase, Web of Science, Wanfang, VIP, and CNKI were systematically searched for eligible studies, and 34 relevant studies were finally selected to be eligible for inclusion.

RESULTS

We found that IL-1A +4845G/T polymorphism was significantly associated with the risk of RA in the overall population (dominant comparison: p = 0.02; overdominant comparison: p = 0.05; allele comparison: p = 0.04), whereas IL-1B +3954C/T polymorphism was significantly associated with the risk of RA in the overall population (overdominant comparison: p = 0.03; allele comparison: p = 0.01) and Asians (recessive comparison: p = 0.007; allele comparison: p = 0.002). In addition, we found that IL-1A -889C/T polymorphism was significantly associated with the risk of SLE in Caucasians (allele comparison: p = 0.04), IL-1B -31T/C polymorphism was significantly associated with the risk of SLE in the overall population (recessive comparison: p = 0.04), and IL-1B -511C/T polymorphism was significantly associated with the risk of SLE in Asians (recessive comparison: p = 0.01; allele comparison: p = 0.03).

CONCLUSIONS

This meta-analysis suggests that IL-1A +4845G/T and IL-1B +3954C/T polymorphisms may influence the risk of RA, whereas IL-1A -889C/T, IL-1B -31T/C, and IL-1B -511C/T polymorphisms may influence the risk of SLE.

Pro-inflammatory cytokine response pre-dominates immuno-genetic pathway in development of rheumatoid arthritis

Rheumatoid arthritis (RA) is a crucial inflammatory joint disease characterized by loss of self-tolerance and severe cartilage loss, autoimmune, and subchondral bone erosions. Cytokines are the key regulators of inflammatory responses. Homeostatic imbalances in pro- and anti-inflammatory cytokine activities can result in pathogenic inflammatory reactions. These imbalances could be initiated by environmental factors but the ability to define the threshold of environmental impact relies on the genetic background of the pro- and anti-inflammatory cytokines. To address this a case-control association study was carried out in 429 individuals from Malayalam speaking ethnic population from South India. Functionally relevant SNPs from IL-10, IL-6, IL-1β and IL-1RN were genotyped using PCR -RFLP and sequencing. Meta-analysis was performed for the associated variants of IL-10, IL-1β. Significant association with RA was observed with IL-1β rs1143634, rs1143627, IL-10 rs1800896, IL-6 rs1800796, rs1800797. The associated SNPs are likely to impact transcriptional activity of a gene. Meta-analysis with global populations also provide evidence that IL-10 and IL-1β could be a global marker for RA. The functional significance of associated risk variants of IL-1β and IL-6 indicate increased production of the pro-inflammatory cytokines while IL-10 risk allele suggest reduced production of anti- inflammatory cytokines. The study concludes that increased production of pro-inflammatory cytokines and reduced production of anti- inflammatory cytokines may influence the Th1/Th2 equilibrium resulting in a triggering of Th1 mediated inflammatory responses in development of RA.

IL1β, IL18, NFKB1 and IFNG gene interactions are associated with severity of rheumatoid arthritis: A pilot study

Rheumatoid arthritis (RA) is an autoimmune disease which can lead to progressive and functional disability. Literature data suggest that some inflammatory proteins are dysregulated in RA patients and its genetic polymorphisms may contribute to the aetiology and pathogenesis of disease in different ethnic groups. Polymorphisms in IL1β, IL18, NFKB1 and IFNG genes were studied in different populations with RA, but the analysis indicated contradictory results. Thereby, we hypothesised that polymorphisms in these genes could have a combined effect on susceptibility to and severity of disease. We evaluated the +3953 C/T IL1β (rs1143634), -137 G/C IL18 (rs187238), -94 ins/del ATTG NFKB1 (rs28362491) and +874 T/A IFNG (rs2430561) polymorphisms in the northeastern Brazilian population. Peripheral blood samples were collected and DNA extraction was conducted. The polymorphisms were evaluated by RFLP and ARMS-PCR. An association was observed in rs1143634 which showed a protective effect against development of RA in carriers of the T allele (OR = 0.58; 95% CI 0.36-0.92; p = .020). In addition, we found an association among genotypes of the rs1143634 with the HAQ index (p = .021) and rs2430561 with DAS28 (p = .029) and CDAI (p = .029). In relation to combined effects of these SNPs (C/C to rs1143634, G/G to rs187238, I/I to rs28362491 and AA to rs2430561) we found a significant association with decreased functional disability (HAQ index p < .001) and ESR (p = .034), indicating a lower disease activity in carriers of these genotypes. GLM analysis confirmed these associations (HAQ (F = 5.497; p < .001) and ESR (F = 2.727; p = .032)). Our analysis indicated that in the studied population +3953 C/T IL-1β (rs1143634), -137 G/C IL-18 (rs187238), -94 ins/del ATTG NFKB1 (rs28362491) and +874 T/A IFNG (rs2430561) polymorphisms can together contribute to RA severity although they do not individually influence the disease.

Interleukin 1α and 1β gene variations are associated with tuberculosis in silica exposed subjects

INTRODUCTION

Silicosis is a fibrotic lung disease resulting from the inhalation of crystalline silica and can be classified as simple or complicated according to the International Labour Organization criteria. Furthermore, individuals exposed to crystalline silica also have a higher risk for the development of tuberculosis (Tb). The contribution of inflammatory cytokines to the risk of silicosis and Tb in different populations has previously been reported. Since genetic background might be related to susceptibility to silicosis and Tb, the study of polymorphisms within IL-1α, IL-1β, and tumor necrosis factor protein-coding genes may contribute to elucidating the genetic basis of these diseases.

METHODS

Single nucleotide polymorphisms (SNPs) were genotyped by polymerase chain reaction using restriction fragment length polymorphism or by Taqman methodology, in a sample of 102 silica-exposed patients from Brazil.

RESULTS

No significant associations were observed between the SNPs studied and the severity of silicosis. However, significant associations were found between Tb and the C allele (odds ratio [OR] = 1.93, 95% confidence interval [CI], 1.01-3.73) and the CC genotype (OR = 2.34, 95% CI, 1.04-5.31) of IL1A -899C>T. The IL1B +3954C>T polymorphism also showed an association with Tb (T allele dominant model OR = 2.38, 95% CI, 1.04-5.41).

CONCLUSION

These preliminary results demonstrate that the IL1A and IL1B gene variations may contribute to some extent to susceptibility to Tb, but not silicosis. However, additional studies are still needed to confirm these results.

Interleukin 1 receptor antagonist gene variable number of tandem repeats polymorphism and cutaneous melanoma

Immunity and cytokines serve crucial roles in cutaneous melanoma. The present study investigated whether a variable number tandem repeat (VNTR) polymorphism of interleukin-1 receptor antagonist (IL-1RA) gene (IL-1RN) located in intron 2 (rs2234663) is associated with cutaneous melanoma. A total of 515 subjects were studied, 133 of which were cutaneous melanoma cases (72 stage I+II non-metastatic melanoma cases and 61 stage III+IV metastatic melanoma cases), and 382 subjects were matching healthy controls from the Friuli-Venezia-Giulia Region located in Northeast Italy, an area with a high melanoma incidence. The IL-1RN-VNTR polymorphism was determined by DNA fragment length analysis following PCR amplification. According to the number of 86-bp repeats, five different IL-1RN alleles were identified: Allele 1 (4-repeats), allele 2 (2-repeats, short allele), allele 3 (5-repeats), allele 4 (3-repeats) and allele 5 (6-repeats). Alleles with three or more 86-bp repeats, i.e. allele 1, 3, 4 and 5 were collectively denoted as long (L) repeats. The present study revealed that IL-1RN-VNTR 1/2 and 2/L genotypes were more frequent among patients with cutaneous melanoma (43.6 and 45.1%, respectively) compared with healthy controls [29.6 and 30.6%, respectively; odds ratio (OR), 1.84; CI, 1.22–2.77; P=0.003; and OR, 1.66; CI, 1.24–2.79; P=0.002, respectively]. Conversely, the IL-1RN-VNTR 1/1 genotype was less frequent among melanoma cases (45.9%) compared with healthy controls (57.9%; OR, 0.62; CI, 0.41–0.92; P=0.017). Comparison of metastatic vs. non-metastatic melanoma cases identified no significant differences. The present study first demonstrated that carriage of the 1/1 IL-1RN-VNTR genotype was protective, whereas 1/2 and 2/L was a risk factor for patients with cutaneous melanoma vs. healthy controls. The short allele 2 was associated with higher expression levels of IL-1RA, a potent competitive inhibitor of the proinflammatory cytokines IL-1α and IL-1β. VNTR-IL-1RN polymorphism may affect susceptibility to melanoma and, thus, it is a potential novel diagnostic biomarker for melanoma. The present study increased the understanding of genetic melanoma susceptibility/carcinogenesis, and may indicate novel strategies in the personalized prevention of cutaneous melanoma.

Lipidoid-siRNA Nanoparticle-Mediated IL-1β Gene Silencing for Systemic Arthritis Therapy in a Mouse Model

Interleukin-1 beta (IL-1β) plays a central role in the induction of rheumatoid arthritis (RA). In the present study, we demonstrated that lipidoid-polymer hybrid nanoparticle (FS14-NP) can efficiently deliver siRNA against IL-1β (siIL-1β) to macrophages and effectively suppress the pathogenesis of experimental arthritis induced by collagen antibody (CAIA mice). FS14-NP/siIL-1β achieved approximately 70% and 90% gene-silencing efficiency in the RAW 264.7 cell line and intraperitoneal macrophages, respectively. Intravenous administration of FS14-NP/siRNA led to rapid accumulation of siRNA in macrophages within the arthritic joints. Furthermore, FS14-NP/siIL-1β treatment lowered the expression of pro-inflammatory cytokines in arthritic joints and dramatically attenuated ankle swelling, bone erosion, and cartilage destruction. These results demonstrate that FS14-NP/siIL-1β may represent an effective therapy for systemic arthritis and other inflammatory disorders.

Association between IL-1β + 3954C/T polymorphism and myocardial infarction risk: A meta-analysis

BACKGROUND

Many studies have reported that the IL-1β + 3954C/T polymorphism (rs1143634) is related to myocardial infarction (MI). To classify the association between IL-1β + 3954C/T and MI susceptibility, we performed a meta-analysis.

METHODS

We retrieved relevant literature from electronic databases (Embase, PubMed, Cochrane, and Web of Science). Pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated with a fixed effect model or a random effect model. Sensitivity analysis and publication bias results are also presented.

RESULTS

Nine eligible studies (2299 controls and 2203 cases) were included. The pooled results showed a significant relationship between MI and IL-1β + 3954C/T in an allelic comparison (T vs C: OR = 1.13, 95% CI 1.02-1.25, I = 0%, PH = .448) and in a dominant model (TC + TT vs CC: OR = 1.15, 95% CI 1.02-1.30, I = 0%, PH = .880). Ethnic subgroup analysis showed similar results in Caucasian populations: an allelic comparison (T vs C: OR = 1.16, 95% CI 1.04-1.29, I = 0%, PH = .701), homozygote model (TT vs CC: OR = 1.36, 95% CI 1.04-1.79, I = 0%, PH = .673), and dominant model (TC + TT vs CC: OR = 1.17, 95% CI 1.02-1.33, I = 0%, PH = .851). In addition, similar effects remained in subgroups analyses of high-quality studies and PCR-RFLP (restriction fragment length polymorphism) data.

CONCLUSION

Our meta-analysis proved that IL-1β + 3954C/T is associated with MI susceptibility, especially among Caucasian populations.

Application of Interleukin-1 Genes and Proteins to Monitor the Status of Chronic Periodontitis

It has been widely reported that periodontitis may lead to bone tissue and teeth loss and result in failure of prosthodontics or implants. Interleukin-1 (IL-1) is a potent proinflammatory cytokine that plays an essential role during the pathogenesis of periodontitis. However, the gene polymorphisms of IL-1α, IL-1β and IL-1RN and the relationship between these protein expressions in healthy people and patients with chronic periodontitis (CP) in China have not been fully elucidated. We investigated the gene polymorphisms and protein expression of IL-1α, IL-1β and IL-1RN in healthy subjects and CP patients, and our data suggest that these gene polymorphisms are associated with CP. The frequency of the C/C genotype of IL-1α was 55% in CP patients, while in the control group it was 20% (p<0.0001). The C/C genotype of IL-1β was also higher in CP patients (51%) than in controls (21%) (p<0.0001). For the 2/2 genotype of IL-1RN, CP patients showed a 30% frequency, while in controls this was 15% (p<0.0001). Protein levels evaluated by enzyme-linked immunosorbent assay demonstrated a significant difference in secretion between patients and controls for IL-1α and IL-1β. These results indicate that genotype and protein production of IL-1α, IL-1β and IL-1RN are associated with CP in a Chinese population, and might be putative risk indicators for chronic periodontitis.

High expression of interleukine-1 receptor antagonist in rheumatoid arthritis: Association with IL1RN*2/2 genotype

Rheumatoid arthritis (RA) is an autoimmune disease characterized by inflammation and pro-inflammatory cytokines production. IL-1Ra is an anti-inflammatory cytokine codified by IL1RN gene that blocks IL-1 signalling. A VNTR polymorphism of 86 bp in IL1RN gene has been associated with RA risk and regulation of IL-1Ra expression. In this study, we determined mRNA and protein expression of IL-1Ra in RA patients and control subjects (CS). This study included 85 RA patients classified according to the ACR/EULAR 2010 criteria and 67 CS. Polymerase chain reaction was used to identify IL1RN VNTR polymorphism, the expression of sIL-1Ra (secreted isoform) mRNA was determined by SYBR Green-based real time quantitave-PCR assay, and IL-1Ra soluble levels quantification was evaluated by ELISA test. RA patients had higher soluble levels of IL-1Ra than CS (p < .01), sIL-1Ra mRNA expression was higher in RA patients compared to CS (p < .01). Carriers of IL1RN*2/2 homozygous genotype show increased IL-1Ra soluble levels compared to IL1RN*long/long and IL1RN*2/long genotypes (p < .05) in the CS group, whereas mRNA expression in carriers of IL1RN*2/2 genotype was 1.2 times higher compared to IL1RN*long/long genotypes in the same group. Regarding RA patients, high expression of sIL-1Ra mRNA on carriers of IL1RN*long/long genotype was observed. Nevertheless, in RA patients IL-1Ra soluble levels among genotypes did not show significant differences. High expression of IL-1Ra in RA patients under treatment or not with antirheumatic drugs was detected. Additionally, carriers of IL1RN*2/2 genotype had higher IL-1Ra expression than carriers of other genotypes.

The role of genetic analysis for predicting outcome of rheumatoid arthritis

INTRODUCTION

Rheumatoid Arthritis (RA) varies from a mild to a severe, unremitting illness characterized by uncontrolled inflammation with consequent damage to cartilage and bone of joints. Individualized therapeutic approaches based on likely outcome would facilitate a personalized therapeutic approach. Areas covered: Genetics is known to contribute a significant component of the variability in RA outcome, estimated at 45-60%. A number of candidate gene studies have been associated with variability in radiologically assessed joint damage; however a more comprehensive genome wide analysis is required to more fully characterize the genetic basis of RA severity. Expert commentary: Genetic profiling of patient presenting with RA has the potential to aid stratification based on predicted prognosis, this would inform the clinical development of a personalized therapeutic approach. It will also result in the identification of novel mediators of tissue damage in RA.

Sex Influences on the Penetrance of IL-1β and IL-1RN Genotypes for Rheumatoid Arthritis in the Chinese Population

Polymorphism (variable number of tandem repeats) in the second intron of the interleukin-1 receptor antagonist ( IL-1Ra) gene and two single nucleotide polymorphisms at positions −511 and +3954 of the IL-1β gene may be associated with an increased risk of rheumatoid arthritis (RA). This study used sex stratification to investigate a correlation of the three genetic polymorphisms with the risk of RA, on patients with RA and healthy controls. Polymerase chain reaction (PCR) and polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) were performed. The frequencies of the IL-1β+ 3954 allele and genotype in female patients were significantly different compared with the controls; but in males, only the frequency of the IL-1β+ 3954 allele was different. The frequency of the IL-1RN genotype in patients was not statistically different compared with the controls; however, the frequency of IL-1RN allele in female patients was different. The association of the three polymorphisms with the susceptibility to RA appears to be significantly affected by gender.

The Clinical Significance of Interleukin-1 Receptor Antagonist +2018 Polymorphism in Rheumatoid Arthritis

OBJECTIVE

Interleukin-1 receptor antagonist (IL-1Ra) acts as an inhibitor of IL-1; which is one of the culprit cytokines in rheumatoid arthritis (RA). Although +2018 polymorphism of IL-1Ra has been implicated in the pathogenesis of RA, its importance remains poorly understood. Hence, the purpose of this study was to determine the clinical significance of interleukin-1 receptor antagonist (IL-1Ra) +2018 polymorphism in RA.

METHODS

Polymerase chain reaction (PCR) and sequencing were used to determine the genotypes of the IL-1Ra +2018 for 77 RA patients and 18 healthy controls. All RA patients were assessed for the disease activity score that includes 28 joints (DAS28) and radiographic disease damage based on Modified Sharp Score (MSS).

RESULTS

The frequency of the T/T and C/T genotypes did not differ significantly (p = 0.893) between the RA patients and the controls. The C/T genotype had significantly higher mean disease activity (DAS 28) and disease damage (MSS) scores with p values of 0.017 and 0.004, respectively. Additionally, the ESR (erythrocyte sedimentation rate), CRP (C-reactive protein), the number of swollen and tender joints were higher for the C/T individuals. On multivariate analysis the CRP, swollen joint count and MSS remained significant with the following p values i.e. 0.045, 0.046 and less than 0.05.

CONCLUSIONS

C/T genotype of IL-1Ra +2018 prognosticates more aggressive disease in RA.

Serum Immune Proteins in Moderate and Severe Chronic Fatigue Syndrome/Myalgic Encephalomyelitis Patients

Immunological dysregulation is present in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME), with recent studies also highlighting the importance of examining symptom severity. This research addressed this relationship between CFS/ME severity subgroups, assessing serum immunoglobulins and serum cytokines in severe and moderate CFS/ME patients. Participants included healthy controls (n= 22), moderately (n = 22) and severely (n=19) affected CFS/ME patients. The 1994 Fukuda Criteria defined CFS/ME and severity scales confirmed mobile and housebound CFS/ME patients as moderate and severe respectively. IL-1β was significantly reduced in severe compared with moderate CFS/ME patients. IL-6 was significantly decreased in moderate CFS/ME patients compared with healthy controls and severe CFS/ME patients. RANTES was significantly increased in moderate CFS/ME patients compared to severe CFS/ME patients. Serum IL-7 and IL-8 were significantly higher in the severe CFS/ME group compared with healthy controls and moderate CFS/ME patients. IFN-γ was significantly increased in severe CFS/ME patients compared with moderately affected patients. This was the first study to show cytokine variation in moderate and severe CFS/ME patients, with significant differences shown between CFS/ME symptom severity groups. This research suggests that distinguishing severity subgroups in CFS/ME research settings may allow for a more stringent analysis of the heterogeneous and otherwise inconsistent illness.

Interleukin-1β and interleukin-6 gene polymorphisms are associated with manifestations of sickle cell anemia

Sickle cell anemia (SCA), a disorder characterized by both acute and chronic inflammation, exhibits substantial phenotypic variability. Interleukin-1 beta (IL-1β) and IL-6 are important in acute and chronic diseases, and their single nucleotide polymorphisms (SNPs) have been considered as predictors of prognosis in several inflammatory conditions. This study aims at exploring possible association of IL-1β and IL-6 SNPs as potential genetic modifiers and or predictors of SCA clinical and laboratory phenotypes. This cross-sectional study involved 107 SCA patients and 110 age, sex and ethnicity-matched healthy individuals. The SNPs were identified by PCR-RFLP for IL-1β (-511C>T and +3954C>T) and IL-6 (-597G>A and -174G>C) genes. Associations between these SNPs and the clinical and laboratory profiles of patients with SCA were then determined. Allelic and genotypic frequencies of IL-1β and IL-6 SNPs between patients with SCA and controls were similar and followed HWE. IL-1β +3954C>T SNP was associated with increased risk of osteonecrosis, elevated pulmonary arterial pressure and lower absolute reticulocyte count, while IL-6 -597G>A was associated with higher likelihood of retinopathy and leg ulcer. These data indicate that IL-1β and IL-6 gene SNPs are associated with SCA complications among Brazilian patients and may act as genetic predictors of SCA clinical heterogeneity.

Association between IL1B (+3954) polymorphisms and IL-1β levels in blood and saliva, together with acute graft-versus-host disease

Graft-versus-host disease (GVHD) is associated with morbidity and mortality in the recipients of allogeneic hematopoietic stem cell transplants (allo-HSCTs). Interleukin-1β (IL-1β) is a potent inflammatory mediator involved in different inflammatory conditions. Therefore, we aimed to investigate the association of IL1B gene polymorphism in recipients and donors in cases in which acute GVHD (aGVHD) has been reported and the impact of this gene polymorphism on the level of cytokines in the blood and saliva. Fifty-eight consecutive allo-HSCT recipients and their donors were prospectively studied. Saliva and/or blood samples were obtained from the recipients and donors to identify the IL1B gene polymorphism, and cytokine levels were assessed by ELISA. Samples were collected weekly from 7 days before transplantation (day -7) to 100 days after allo-HSCT (day+100), for a total of 16 weeks or until death. aGVHD occurred in 27 individuals evaluated. A significant association was identified between the IL1B polymorphism in the donor and aGVHD development in the corresponding recipients. However, no significant association was detected between the IL1B polymorphism in recipients and the development of aGVHD. In the recipients who were diagnosed with aGVHD, the level of IL-1β in the saliva and blood were increased. In the saliva, IL-1β levels increased progressively from the time before the diagnosis of aGVHD until weeks after the diagnosis, whereas in the blood, IL-1β peak levels could be observed within the time allotted for diagnosis, followed by a decrease in the levels. In addition, we observed a significant association between the IL1B genotype of the recipient (CC) and high IL-1β levels in the saliva at week 13. In conclusion, IL-1β could be considered a useful predictor of aGVHD development.

Potential of ayurgenomics approach in complex trait research: leads from a pilot study on rheumatoid arthritis

Background

Inconsistent results across association studies including Genome-wide association, have posed a major challenge in complex disease genetics. Of the several factors which contribute to this, phenotypic heterogeneity is a serious limitation encountered in modern medicine. On the other hand, Ayurveda, a holistic Indian traditional system of medicine, enables subgrouping of individuals into three major categories namely Vata, Pitta and Kapha, based on their physical and mental constitution, referred to as Prakriti. We hypothesised that conditioning association studies on prior risk, predictable in Ayurveda, will uncover much more variance and potentially open up more predictive health.

Objectives and Methods

Identification of genetic susceptibility markers by combining the prakriti based subgrouping of individuals with genetic analysis tools was attempted in a Rheumatoid arthritis (RA) cohort. Association of 21 markers from commonly implicated inflammatory and oxidative stress pathways was tested using a case-control approach in a total cohort comprising 325 cases and 356 controls and in the three subgroups separately. We also tested few postulates of Ayurveda on the disease characteristics in different prakriti groups using clinico-genetic data.

Results

Inflammatory genes like IL1β (C-C-C haplotype, p = 0.0005, OR = 3.09) and CD40 (rs4810485 allelic, p = 0.04, OR = 2.27) seem to be the determinants in Vata subgroup whereas oxidative stress pathway genes are observed in Pitta (SOD3 rs699473, p = 0.004, OR = 1.83; rs2536512 p = 0.005; OR = 1.88 and PON1 rs662, p = 0.04, OR = 1.53) and Kapha (SOD3 rs2536512, genotypic, p = 0.02, OR = 2.39) subgroups. Fixed effect analysis of the associated markers from CD40, SOD3 and TNFα with genotype X prakriti interaction terms suggests heterogeneity of effects within the subgroups. Further, disease characteristics such as severity was most pronounced in Vata group.

Conclusions

This exploratory study suggests discrete causal pathways for RA etiology in prakriti based subgroups, thereby, validating concepts of prakriti and personalized medicine in Ayurveda. Ayurgenomics approach holds promise for biomarker discovery in complex diseases.

Rheumatoid Arthritis-associated Polymorphisms at 6q23 Are Associated with Radiological Damage in Autoantibody-positive RA

Objective.

Recent studies have identified 6q23 as an important susceptibility locus for rheumatoid arthritis (RA), with risk alleles at 3 single-nucleotide polymorphisms combining to give an effect size greater than that of these markers individually. We investigated whether these polymorphisms are also associated with disease severity measured by radiological damage.

Methods.

We studied 927 patients from a cross-sectional RA cohort. Median Larsen scores (LS) read from radiographs taken at study entry were compared by genotype at rs6920220, rs13207033, and rs5029937 according to a dominant model using negative binomial regression with stratification for autoantibody status.

Results.

Median LS was associated with genotype at rs6920220 [LS 31 GG vs 36 GA/AA (p = 0.02) in cyclic citrullinated peptide+ (CCP) RA] and rs13020220 [LS 37 GG vs 29 GA/AA (p = 0.02) in CCP+ RA] only in autoantibody-positive RA, with no association at rs5029937. Association was stronger for these markers in combination [LS 28 vs 42 for lowest vs highest risk genotype combination in rheumatoid factor positivity (p = 0.007), LS 28 vs 37 for anti-CCP+ (p = 0.01)].

Conclusion.

Established RA risk markers at 6q23 are associated also with radiographic severity in autoantibody-positive RA; as for susceptibility, the association for these markers in combination is stronger than that for markers alone.

Precipitating and perpetuating factors of rheumatoid arthritis immunopathology: linking the triad of genetic predisposition, environmental risk factors and autoimmunity to disease pathogenesis

Rheumatoid arthritis (RA) is considered to occur when genetic and environmental factors interact to trigger immunopathological changes and consequently an inflammatory arthritis. Over the last few decades, epidemiological and genetic studies have identified a large number of risk factors for RA development, the most prominent of which comprise cigarette smoking and the shared epitope alleles. These risks appear to differ substantially between anti-cyclic citrullinated peptide (ACPA)-positive and ACPA-negative disease. In this article, we will summarise the risk factors for RA development that have currently been identified, outlining the specific gene-environment and gene-gene interactions that may occur to precipitate and perpetuate autoimmunity and RA. We will also focus on how this knowledge of risk factors for RA may be implemented in the future to identify individuals at a high risk of disease development in whom preventative strategies may be undertaken.

Gene polymorphisms and pharmacogenetics in rheumatoid arthritis

Rheumatoid arthritis (RA) is a systemic, chronic and inflammatory disease of unknown etiology with genetic predisposition. The advent of new biological agents, as well as the more traditional disease-modifying antirheumatic drugs, has resulted in highly efficient therapies for reducing the symptoms and signs of RA; however, not all patients show the same level of response in disease progression to these therapies. These variations suggest that RA patients may have different genetic regulatory mechanisms. The extensive polymorphisms revealed in non-coding gene-regulatory regions in the immune system, as well as genetic variations in drug-metabolizing enzymes, suggest that this type of variation is of functional and evolutionary importance and may provide clues for developing new therapeutic strategies. Pharmacogenetics is a rapidly advancing area of research that holds the promise that therapies will soon be tailored to an individual patient’s genetic profile.

An overview on the genetic of rheumatoid arthritis: a never-ending story

Rheumatoid arthritis (RA) is a chronic, systemic, inflammatory, multi-factorial disease sustained by environmental and genetic factors. These seem to be necessary but not sufficient in the disease development, nonetheless they can be responsible of different clinical pictures and response to therapy, and they can represent potential therapeutic targets. Several genes have been indicated so far in the pathogenesis of RA. The most important region is the Human Leukocyte Antigen (HLA) that contributes to approximately half of the genetic susceptibility for RA. The association seems to be stronger or specific for anti-citrullinated protein antibodies positive disease. Several alleles in the epitope-recognition part of the HLA molecule that show the highest association with RA susceptibility, also share a common string of amminoacid residues (the so-called shared-epitope hypothesis). Other variants in potentially pathogenic genes located in non-MHC regions have been implicated by recently performed genome wide analysis studies. These genes include PTPN22, TRAF1-C5, PADI4, STAT4. Other polymorphisms seem to be responsible for more aggressive disease phenotype such as those located at TNF, IL-1, IL-6, IL-4, IL-5, OPN, PRF1. However, still nowadays, the genetic background of RA remains to be clearly depicted, and the efforts in the post-genomic era can bring to an estimation of the real likelihood of the genetic effect on RA. Finally, the discovery of new genes associated with the disease can be relevant in finding potential biomarkers, potentially useful in disease diagnosis and treatment.

IL10 GGC Haplotype Is Positively and HLA-DQA1*05-DQB1*02 Is Negatively Associated with Radiographic Progression in Undifferentiated Arthritis

Objective.

In rheumatoid arthritis (RA), many genetic markers, such as the shared-epitope (SE) alleles, are described in association with radiographic progression, but limited data are available on undifferentiated arthritis (UA). We investigated whether single-nucleotide polymorphisms (SNP) and haplotypes in immune response genes and HLA class II alleles are associated with radiographic progression in patients with early UA.

Methods.

Progression of radiographic damage was determined in white Dutch patients with early UA after 2 years of followup. Severe progression was defined as an increase in Sharp/van der Heijde Score ≥ 5 points after 2 years of followup. The remainder was classified as mild. These SNP were genotyped by Taqman technology: tumor necrosis factor (TNF) −1031, −863, −857, −308, −238; lymphotoxin-α (LTA) +368, +252; interleukin 10 (IL10) −2849, −1082, −819; IL1A −889, IL1B −31, +3953; and IL1RN +2018. Carriage of SE alleles and HLA-DQA1*05-DQB1*02 haplotype was established. These markers were analyzed in relation to radiographic progression.

Results.

Forty-eight out of 151 patients with early UA had severe radiographic progression. Severe radiographic progression was associated with an increased carrier frequency of SE alleles (OR 5.12, 95% CI 2.0–13.1, p < 0.001) and IL10 GGC haplotype (OR 2.8, 95% CI 1.4–5.8, p = 0.003). Mild radiographic progression was associated with the HLA-DQA1*05-DQB1*02 haplotype (OR 0.3, 95% CI, 0.1–0.8, p = 0.013) and with allele TNF −308A (OR 0.4, 95% CI, 0.2–0.9, p = 0.02).

Conclusion.

The SE and the IL10 GGC haplotype are associated with severe progression of radiographic damage, in contrast to the DQA1*05-DQB1*02 haplotype and the TNF −308A allele, which are associated with mild radiographic progression in early UA.

Variable number of tandem repeat polymorphisms of the interleukin-1 receptor antagonist gene IL-1RN: a novel association with the athlete status

BACKGROUND

The interleukin-1 (IL-1) family of cytokines is involved in the inflammatory and repair reactions of skeletal muscle during and after exercise. Specifically, plasma levels of the IL-1 receptor antagonist (IL-1ra) increase dramatically after intense exercise, and accumulating evidence points to an effect of genetic polymorphisms on athletic phenotypes. Therefore, the IL-1 family cytokine genes are plausible candidate genes for athleticism. We explored whether IL-1 polymorphisms are associated with athlete status in European subjects.

METHODS

Genomic DNA was obtained from 205 (53 professional and 152 competitive non-professional) Italian athletes and 458 non-athlete controls. Two diallelic polymorphisms in the IL-1beta gene (IL-1B) at -511 and +3954 positions, and a variable number tandem repeats (VNTR) in intron 2 of the IL-1ra gene (IL-1RN) were assessed.

RESULTS

We found a 2-fold higher frequency of the IL-1RN 1/2 genotype in athletes compared to non-athlete controls (OR = 1.93, 95% CI = 1.37-2.74, 41.0% vs. 26.4%), and a lower frequency of the 1/1 genotype (OR = 0.55, 95% CI = 0.40-0.77, 43.9% vs. 58.5%). Frequency of the IL-1RN 2/2 genotype did not differ between groups. No significant differences between athletes and controls were found for either -511 or +3954 IL-1B polymorphisms. However, the haplotype (-511)C-(+3954)T-(VNTR)2 was 3-fold more frequent in athletes than in non-athletes (OR = 3.02, 95% CI = 1.16-7.87). Interestingly, the IL-1RN 1/2 genotype was more frequent in professional than in non-professional athletes (OR = 1.92, 95% CI = 1.02-3.61, 52.8% vs. 36.8%).

CONCLUSIONS

Our study found that variants at the IL-1ra gene associate with athletic status. This confirms the crucial role that cytokine IL-1ra plays in human physical exercise. The VNTR IL-1RN polymorphism may have implications for muscle health, performance, and/or recovery capacities. Further studies are needed to assess these specific issues. As VNTR IL-1RN polymorphism is implicated in several disease conditions, athlete status may constitute a confounding variable that will need to be accounted for when examining associations of this polymorphism with disease risk.

Genetic variants in inflammation pathway genes and asthma in glioma susceptibility

Single nucleotide polymorphisms (SNPs) in inflammation-related genes have previously been shown to alter risks of developing various cancers. However, the effects of such SNPs on glioma risk remain unclear. We used a multistrategic approach to elucidate the relationship between glioma risk, asthma/allergies, and 23 literature-based functional SNPs in 11 inflammation genes. Genotyping was conducted on 373 histologically confirmed adult glioma patients and 365 cancer-free controls from the Harris County Brain Tumor Study. Deviations from the Hardy-Weinberg equilibrium were assessed using the chi(2)-test, and Akaike's information criterion was used to determine the best genetic model for each SNP. Odds ratios (ORs) were calculated both for each SNP individually and for grouped analyses, examining the effects of the numbers of adverse alleles on glioma risk in participants with and without asthma. In the single-locus analysis of the 23 examined SNPs, 1 pro-inflammatory and 2 anti-inflammatory gene SNPs were significantly associated with glioma risk (COX2/PTGS2, rs20417 [OR = 1.41]; IL10, rs1800896 [OR = 1.57]; and IL13, rs20541 [OR = 0.39], respectively). When we examined the joint effects of the risk-conferring alleles of these 3 SNPs, we found a significant trend indicating that the risk increases as the number of adverse alleles increase (P = .005). Stratifying by asthma status, we found that this dose-response-like trend of increasing risk is only present among those without asthma/allergies (P < .0001). Our study indicates that polymorphisms in inflammation genes are associated with glioma susceptibility, especially when a history of asthma/allergies is absent.

Association between interleukin-1 beta polymorphism (+3953) and obesity

It now appears that obesity is associated with a low-grade inflammation of white adipose tissue resulting from chronic activation of the innate immune system as interleukin-1 beta (IL-1). Previous investigations have described a positive association between IL-1 beta +3953 (C>T) gene polymorphism (rs 1143634) and obesity, suggesting functional effects on fat mass, fat metabolism and body mass. However, it is necessary to determine if these results occur in other populations and if they are influenced by sex and age. Therefore, we performed a case-control study using 880 Caucasian subjects (59.7+/-11.9 years old) from the Brazilian Aging Research Program (non-overweight=283, overweight=334, obese=263) previously investigated in genetic studies, in whom we analyzed the IL-1 beta +3953C/T polymorphism. We observed higher T allele (CT/TT) frequency in non-overweight than overweight and obese groups. The odds ratio showed 1.340 (95% CI: 1.119-1.605) times more chance of the obese group being CC carriers compared to non-overweight group independent of sex and age. This study corroborates the idea that the IL-1 system is linked to the development of obesity.

Genotype and haplotype determination of interleukin (IL) 1 beta (g. -511C>T and g. +3954C>T) and IL-1RN in polycystic ovary syndrome

The distribution of genotype frequencies, allele frequencies, and haplotype frequencies of variable number of tandem repeats (VNTR) in interleukin (IL) 1RN and IL-1beta (-511C > T, exon-5C.>T) polymorphism demonstrated a positive association with the occurrence of polycystic ovary syndrome (PCOS). The carriage of allele V of IL-1RN and allele E1 of exon-5 on the IL-1beta gene may increase the risk of PCOS.

TNF receptor I polymorphism is associated with persistent palindromic rheumatism

OBJECTIVES

To investigate the association between tumour necrosis factor-alpha (TNFalpha), TNF receptor superfamily member 1A (TNFRSF1A, also known as TNFRI), TNFRSF1B (TNFRII), and interleukin-1beta (IL-1beta) single nucleotide polymorphisms (SNPs) and the susceptibility to persistent palindromic rheumatism (PR).

METHODS

Fifty-six unrelated patients with persistent PR and 100 unrelated healthy controls were genotyped for TNFalpha -308G/A, -238G/A, and +488G/A, TNFRSF1A -609G/T and +36A/G, TNFRSF1B +676T/G and +1663G/A, and IL-1beta -511C/T, -31T/C, and +3954C/T using real-time polymerase chain reaction (RT-PCR).

RESULTS

The TNFRSF1A +36G allele [odds ratio (OR) = 3.94, p = 0.003, corrected p (p(c)) = 0.03] and the TNFRSF1A +36AG genotype (OR = 4.81, p = 0.002, p(c) = 0.04) were significantly associated with persistent PR. The frequency of TNFRSF1B +676T/+1663A was increased in PR patients (OR = 2.12, p = 0.01), but failed to reach statistical significance after Bonferroni correction. No correlation was observed between persistent PR and TNFalpha, TNFRSF1A -609G/T, or IL-1beta SNPs.

CONCLUSIONS

The results of this study provide evidence of an association between persistent PR and SNPs within the TNFRSF1A gene, and suggest that TNFRI is involved in the aetiopathogenesis of PR.

Interleukin-1beta gene (IL-1beta) polymorphisms (SNP -511 and SNP +3953) in thyroid-associated ophthalmopathy (TAO) among the Polish population

OBJECTIVE

The aim of this study was to evaluate whether the IL-1beta gene could be a genetic marker of the thyroid-associated ophthalmopathy (TAO) development.

MATERIALS AND METHODS

The IL-1beta gene polymorphisms at -511 and +3953 regions in 117 TAO patients of Polish origin (ATA/NOSPECS class III or greater) and in 106 controls were studied.

RESULTS

We found no significant differences in the frequencies of genotypes and allelic variants for SNP -511 and SNP +3953 between the controls and the studied groups.

CONCLUSIONS

No association between the IL-1beta polymorphisms and the TAO existed, so those polymorphisms are not suitable genetic markers for TAO.