Association of MICA and NKG2D genetic variants with disease susceptibility and outcome of anti-TNF therapy in patients with axial spondyloarthritis

OBJECTIVES

The disruption of the NKG2D-MICA axis can induce an enhanced immune response and promote autoimmune processes during axial spondyloarthritis (axSpA) pathogenesis. We aimed to investigate potential relationships between selected single nucleotide polymorphisms within the MICA and NKG2D genes and disease susceptibility and clinical parameters in axSpA patients treated with TNF inhibitors.

METHODS

Genotyping of MICA rs1051792 and NKG2D rs1154831, rs1049174, and rs2255336 was performed in 163 axSpA patients and 234 healthy controls using a real-time PCR method.

RESULTS

MICA rs1051792 A allele was more common in patients than in controls (p<0.0001). Patients with the AA genotype showed greater disease activity score (BASDAI) after three (p=4×10-4) and six (p=0.032) months of treatment compared to G carriers. After three months of therapy with anti-TNFs, the MICA AA homozygosity occurred more often in non-responsive or moderately responsive patients than good responders with the same genotype (p=1×10-4). Additionally, patients bearing the NKG2D rs1154831 CC genotype demonstrated lower BASDAI scores (p=0.035) and were significantly more common among subjects with a good outcome (p=0.004) after six months of treatment.

CONCLUSIONS

These results suggest that MICA and NKG2D gene polymorphisms may be biomarkers associated with disease susceptibility and clinical outcomes after anti-TNF therapy in axSpA patients and imply a rather less favourable effect of the MICA A and NKG2D G genetic variants.

AB0763 Personal approach in axial spondyloarthropathy management

Background

Spondyloarthropathies (SpAs) are a group of diseases characterized by arthritis in the spine (axialSpA - axSpA) and peripheral joints, and extra-articular symptoms like uveitis, psoriasis or inflammatory bowel diseases. The onset of the disease is difficult to observe. Due to the lack of a pathognomonic test, diagnosis is based on a combination of physical examination, laboratory test and imaging results. The pathogenesis of SpAs is not fully understood, and genetic, environmental and immunological factors are assumed to play a pivotal role.

Objectives

The study aimed to evaluate selected polymorphisms (ERAP1 rs2287987, ERAP2 rs2549782, TNF rs1800629, TNFRSF1B rs1061622, FCGR2A rs1801274) as prognostic factors of clinical presentations, and response predictors of anti-TNF treatment in axSpA patients.

Methods

The study enrolled 216 Caucasians: 106 axSpA patients and 110 healthy controls. AS patients were diagnosed according to modified New York criteria, while nr-axSpA patients were diagnosed according to ASAS criteria. Genotyping was performed using LightSNiP assays on the Real-Time PCR Instrument. Clinical data were assessed at baseline, as well as after three and six months of anti-TNF treatment. In addition, information’s about extra-articular symptoms were collected.

Results

The statistical analysis revealed that TNFRSF1B rs1061622-GG was significantly associated with a higher VAS score at baseline (TT + TG vs GG, p = 0.001), and a higher BASDAI score corrected for the first therapy cycle (X1C BASDAI: TT + TG vs GG, p = 0.005). Moreover, homozygotes were more frequently observed with a lack of BASDAI improvement after six months (X1C BASDAI: TT+GG vs TG, p = 0.045, OR = 2.46, 95%CI 1.00-6.12).

ERAP1 rs2287987- GG was more frequently observed with enthesitis (AA vs G+, p = 0.049, OR = 4.636, 95%CI 1.101-21.24). The GG genotype of TNFRSF1B rs1061622 was more common in patients with uveitis than TT variant (GG vs TT, p =0.042, OR = 5, 95%CI 1.08-20).

Associations between genetic variants and clinical outcomes were evaluated using laboratory parameters. A lack of the ESR improvement after six months of treatment was more frequently observed within ERAP1 rs2287987-AG (AG vs AA + GG, p = 0.027, OR = 2.72, 95%CI 1.115-6.137) and TNFRSF1B rs1061622- TT (TT vs G+, p = 0.020, OR = 3, 95%CI 1.27-6.9) compared to other genotypes. After three months of therapy, the GG variant of ERAP2 rs2549782 polymorphism was more common among individuals with the lack of ESR improvement than T allele carriers (GG vs T+, p = 0.037, OR = 2.76, 95%CI 1.13-6.72).

Differences were also detected between the FCGR2A rs1801274 polymorphism and X1CBASDAI score after six months. The low disease activity (BASDAI < 3) and BASDAI improvement was more frequently observed in patients carrying the A allele than the GG genotype (AA+AG vs GG, p = 0.028, OR = 4.545, 95%CI 1.337-16 and p = 0.012, OR = 6.212, 95%CI 1.683-20.47, respectively). The AG genotype was more common among patients with remission (BASDAI < 2) compared to homozygotes (AG vs AA+GG, p = 0.046, OR = 2.36, 95%CI 1.05-5.13).

Conclusion

Genetic profiling of patients will help to identify those at risk of high initial disease activity or the presence of extra-articular symptoms. Identifying patients less responsive to treatment may allow selecting a drug with an appropriate efficacy profile.

Acknowledgements

This work was supported by the grant from Wroclaw Medical University (Poland) STM.A270.20.153.

Disclosure of Interests

Bartosz Bugaj: None declared, Joanna Wielinska: None declared, Jerzy Swierkot Speakers bureau: For Abbvie, Roche, Lilly, Sandoz, Pfizer, Medac, MSD, Novartis, UCB, Katarzyna Bogunia-Kubik: None declared

Searching for New Genetic Biomarkers of Axial Spondyloarthritis

Background: Axial spondyloarthritis (axSpA) is a chronic inflammatory condition of the spine. In addition to musculoskeletal symptoms, there are also extra-articular manifestations. The aim of this study was to search for new biomarkers associated with the clinical presentation and treatment response in axSpA patients. Methods: In this study, 106 axSpA patients and 110 healthy controls were enrolled. Six single-nucleotide polymorphisms (SNPs) were selected for genotyping: ERAP1 rs2287987, ERAP2 rs2549782, TNF rs1800629, TNFRSF1A rs767455, TNFRSF1B rs1061622, and FCGR2A rs1801274. Participants were examined at baseline and after 12 and 24 weeks of anti-TNF therapy. Results: SNPs associated with high axSpA initial activity were TNFRSF1A rs767455 and TNFRSF1B rs1061622 (p < 0.008). The ERAP1 rs2287987 AA genotype was more frequently observed in patients with enthesitis (AA vs. G+, p = 0.049), while the TNFRSF1B rs1061622 GG genotype was more common in participants with uveitis (GG vs. TT, p = 0.042). Potential in predicting anti-TNF treatment response was demonstrated by ERAP1 rs2287987, ERAP2 rs2549782, TNFRSF1B rs1061622, and FCGR2A rs1801274. Conclusions: SNPs can be used to identify patients at risk of severe disease to initiate treatment earlier. Genetic testing will allow clinicians to choose the right drug for the patient.

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

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

IL-33 Gene Polymorphisms as Potential Biomarkers of Disease Susceptibility and Response to TNF Inhibitors in Rheumatoid Arthritis, Ankylosing Spondylitis, and Psoriatic Arthritis Patients

Objective

Rheumatoid arthritis (RA), ankylosing spondylitis (AS), and psoriatic arthritis (PsA) belong to inflammatory rheumatic diseases, the group of conditions of unknown etiology. However, a strong genetic component in their pathogenesis has been well established. A dysregulation of cytokine networks plays an important role in the development of inflammatory arthritis. Interleukin 33 (IL-33) is a recently identified member of the IL-1 family. To date, the significance of IL-33 in inflammatory arthritis has been poorly studied. This research aimed to investigate the potential of IL-33 gene polymorphisms to serve as biomarkers for disease susceptibility and TNF inhibitor response in RA, AS, and PsA patients.

Materials and Methods

In total, 735 patients diagnosed with RA, AS, and PsA and 229 healthy individuals were enrolled in the study. Genotyping for three single nucleotide polymorphisms (SNPs) within the IL-33 gene, namely, rs16924159 (A/G), rs10975519 (T/C), and rs7044343 (C/T), was performed using polymerase chain reaction amplification employing LightSNiP assays.

Results

In the present study, the IL-33 rs10975519 CC genotype was associated with a decreased risk of developing RA in females, while the IL-33 rs16924159 polymorphism was associated with the efficacy of anti-TNF therapy and clinical parameters for RA and AS patients. The IL-33 rs16924159 AA genotype correlated with higher disease activity and worse clinical outcomes in RA patients treated with TNF inhibitors, and AS patients carrying the IL-33 rs16924159 AA genotype had higher disease activity and a worse response to anti-TNF therapy. That indicates a deleterious role of the IL-33 rs16924159 AA genotype in the context of RA, as well as AS.

Conclusions

The obtained results suggest that IL-33 gene polymorphisms might be potential candidate biomarkers of disease susceptibility and anti-TNF treatment response in patients with inflammatory rheumatic diseases.

Polymorphisms within the RANK and RANKL Encoding Genes in Patients with Rheumatoid Arthritis: Association with Disease Progression and Effectiveness of the Biological Treatment

Inconsistency of the results regarding the genetic variability within genes coding for receptor activator of nuclear factor κB (RANK) and its ligand (RANKL) in rheumatoid arthritis (RA) prompted us to study the RANK and RANKL polymorphisms as potential biomarkers associated with disease predisposition and response to anti-TNF treatment in a group of Polish patients with RA. This study enrolled 318 RA patients and 163 controls. RANK (rs8086340, C > G; rs1805034, C > T) and RANKL (rs7325635, G > A; rs7988338 G > A) alleles were determined by real-time PCR with melting curve analysis and related with clinical parameters. In addition, RANKL serum levels were measured by ELISA. The RANK rs8086340-G allele was overrepresented among patients as compared to controls (OD = 1.777, p = 0.038). C-reactive protein (CRP) levels were significantly (p < 0.05) associated with RANK rs8086340 polymorphism and were higher in the CC-homozygotes at the baseline while lower in the GG-carriers at the 12th week of the treatment. At the latter time point RANKL rs7325635-GG-positive patients also showed significantly lower CRP concentrations. Higher alkaline phosphatase levels before induction of anti-TNF therapy were observed in RANK rs8086340 and RANK rs1805034 CC homozygotes (p = 0.057 and p = 0.035, respectively). The GG homozygosity of both RANKL single nucleotide polymorphisms was significantly associated with the number of swollen joints (rs7988338 and rs7325635, before and at the 12th week of therapy, respectively, p < 0.05 in both cases). These results imply that polymorphisms within the RANK and RANKL genes affect RA susceptibility and anti-TNF treatment outcome.

Association of MICA-129Met/Val polymorphism with clinical outcome of anti-TNF therapy and MICA serum levels in patients with rheumatoid arthritis

MHC class I polypeptide-related sequence A (MICA) is a stress-induced protein involved in activation of NK and T cells through interaction with NKG2D receptor. These molecules are atypically expressed in synovium of patients diagnosed with rheumatoid arthritis (RA). A total of 279 patients with RA, qualified to TNF-blockade therapy, were genotyped for MICA rs1051792 SNP. The effectiveness of anti-TNF agents was assessed with European League Against Rheumatism criteria. Significant relationship between MICA rs1051792 and outcome of TNF-blockade therapy has been found. The MICA rs1051792 GG genotype was overrepresented in patients non-responsive to anti-TNF drugs in comparison with other genotypes (p = 0.010). On the other hand, beneficial therapeutic response was more frequently detected among RA subjects possessing heterozygous genotype than those with homozygous genotypes (p = 0.003). Furthermore, increased MICA concentrations in serum were observed in patients possessing MICA rs1051792 GG genotype as compared with those with GA or AA genotypes (p = 1.8 × 10^-5). The results from this study indicate the potential influence of MICA rs1051792 polymorphism on modulation of therapeutic response to TNF-blockade treatment in RA.

[Alcohol--when it's beneficial to your health?]

Ethyl alcohol is the most commonly used psychoactive agent. It's average consumption in Poland totaled 9.67 liters per capita in 2013. Ethanol's biotransformation rate in an adult ranges from 7 to 10 grams per hour. The basic metabolism takes place in the liver through the oxidation involving NAD+. The alcohol is transformed first into acetaldehyde and then into acetic acid. In higher blood concentrations or in alcoholism, cytochrome's P-450 coenzyme CYP2E1 also plays an important role in this process. Alcohol is responsible for nearly 50% of annual deaths, mostly caused by an accident due to alcohol intoxication while driving. Studies were performed to determine the influence ethanol has on the human body and how it impacts the progression of illnesses such as senile dementia, cardiovascular diseases or osteoporosis. Scientists' attention was drawn to the possibility of ethyl alcohol's usage resulting in a reduction in an overall mortality rate, however the beneficial effects were observed only during a slight and moderate consumption. Higher doses of alcohol were associated with a decline in patient's condition. The purpose of this dissertation is an attempt to answer the question, whether the alcohol can be beneficial to the user's health and if so, in what doses? The importance of this topic comes from the fact that due to the alcohol being widely available, determining the influence it has on human body is vital for public health. Original articles and reviews were used to summarize the results of studies regarding the topic.

[Potential applications of marijuana and cannabinoids in medicine]

Cannabinoids, psychoactive substances present in cannabis, have been known to mankind for hundreds of years. Apart from 9-tetrahydrocannabinol (THC) substances found in the cannabis herb with the highest toxicological value are cannabidiol (CBD) and cannabinol (CBN). The discovery of CB1 and CB2 receptors, located in various tissues (ranging from the brain to peripheral tissues), has defined the potential objective of these new chemical substances' effects. Many studies on the application of cannabinoids in the treatment of various diseases such as diabetes, neoplasms, inflammatory diseases, neurological conditions, pain and vomitting were conducted. Drugs containing e.g. THC appear on the pharmaceutical market. Substances affecting cannabinoid receptors may show beneficial effects, but they may also cause the risk of side effects related mainly to the inhibition of central nervous system. The purpose of this dissertation is the analysis, whether the substances responsible for the effects of marijuana, can find application in medicine. Original articles and reviews were used to summarize the results of studies connected to the topic.

Widespread occurrence of the Tc1 transposon family: Tc1-like transposons from teleost fish

We characterized five transposable elements from fish: one from zebrafish (Brachydanio rerio), one from rainbow trout (Salmo gairdneri), and three from Atlantic salmon (Salmo salar). All are closely similar in structure to the Tc1 transposon of the nematode Caenorhabditis elegans. A comparison of 17 Tc1-like transposons from species representing three phyla (nematodes, arthropods, and chordates) showed that these elements make up a highly conserved transposon family. Most are close to 1.7 kb in length, have inverted terminal repeats, have conserved terminal nucleotides, and each contains a single gene encoding similar polypeptides. The phylogenetic relationships of the transposons were reconstructed from the amino acid sequences of the conceptual proteins and from DNA sequences. The elements are highly diverged and have evidently inhibited the genomes of these diverse species for a long time. To account for the data, it is not necessary to invoke recent horizontal transmission.