Inflammation-related cytokine gene polymorphisms in Behçet's disease

TNFα rs1800629 Polymorphism and Response to Anti-TNFα Treatment in Behçet Syndrome: Data from an Italian Cohort Study

Tumor Necrosis Factor-alpha (TNFα) rs1800629 (-308G>A) is a single nucleotide polymorphism (SNP) related to variable responses to anti-TNFα therapy. This therapy is efficient in severe and refractory manifestation of Behçet syndrome (BS), an auto-inflammatory systemic vasculitis. We investigated (1) the association between rs1800629 genotypes and responses to therapy and (2) the correlation between SNP and clinical patterns in a cohort of 74 BS Italian patients receiving anti-TNFα therapy with a follow-up of at least 12 months. The rs1800629 was genotyped through amplification, direct sequencing and bioinformatics analyses. The rs1800629 GG and GA genotypes were assessed as predictors of outcomes dividing the patients between therapy responders and non-responders. The rs1800629 GG and GA genotypes were found, respectively, in 59/74 (79.7%) and 15/74 BS patients (21.3%) (p < 0.05). We identified 16/74 (21.9%) non-responder patients, of which 9/16 (56.3%) showed the GG genotype and 7/16 (43.7%) the GA genotype. A total of 50/58 (86.2%) responder patients showed the GG genotype, and 8/58 (13.8%) the GA genotype (p < 0.05). The percentage of non-responder females (68.8%) was significantly higher than non-responder males (31.2%) (p < 0.05). No correlation between SNP and clinical patterns was observed. To successfully include rs1800629 as a predictive biomarker of TNFα inhibitor response, genome-wide association studies in larger, well-characterised cohorts are required.

Association between Interleukin-10 Gene Polymorphisms and Behcet's Disease Susceptibility: Evidence from a Meta-Analysis

Epidemiological studies have demonstrated that interleukin-10 (IL-10) polymorphisms may be associated with the development of Behcet's disease (BD). However, the published results were inconsistent. Therefore, this meta-analysis was conducted to derive a more precise relationship between IL-10 polymorphisms and BD susceptibility. Online databases (PubMed, Embase, Science Citation Index (SCI), CNKI, and WanFang) were searched to identify eligible studies. Odds ratio (OR) and a 95% confidence interval (CI) were applied to assess the relationship strength between IL-10 -1082A>G (rs1800896), -819T>C (rs1800871), and -592A>C (rs1800872) polymorphisms and BD susceptibility. Publication bias, sensitivity, and cumulative analyses were conducted to measure the robustness of our findings. Finally, fifteen articles (36 independent case-control studies) involving 5,971 patients and 8,913 controls were included. Overall, significant associations between -819T>C polymorphisms and BD risk were observed in the total population (C vs. T: OR = 0.72, 95%CI = 0.67‐0.77, P < 0.01, I² = 36.6%; TC vs. TT: OR = 0.73, 95%CI = 0.66‐0.80, P < 0.01, I² = 23.0%; CC vs. TT: OR = 0.52, 95%CI = 0.39‐0.70, P < 0.01, I² = 53.7%; TC+CC vs. TT: OR = 0.67, 95%CI = 0.61‐0.71, P < 0.01, I² = 22.1%; and CC vs. TT+TC: OR = 0.66, 95%CI = 0.53‐0.82, P < 0.01, I² = 57.8%). Moreover, the IL-10 -592 A>C polymorphism and the ACC haplotype exhibited a significant, protective effect against BD susceptibility. In summary, our meta-analysis suggested that IL-10 gene polymorphisms may play a salient role for BD development.

Exploring the association of IL-10 polymorphisms in Behcet's disease: a systematic review and meta-analysis

Background

Polymorphisms in the interleukin-10 (IL-10) gene have been studied in various ethnic groups for possible association with Behçet’s disease (BD). This study aimed to perform a meta-analysis of eligible studies to calculate the association of IL-10 polymorphisms with BD.

A systematic literature search was carried out in PubMed, Embase, Web of Science, and Scopus databases to identify relevant publications, and extracted the respective results. Pooled odds ratio (OR) with 95% confidence interval (CI) was used to evaluate the power of association with a random-effects model.

Results

A total of 19 articles, consisting of 10,626 patients and 13,592 controls were included in the meta-analysis. The meta-analysis revealed significant associations in allelic and genotypic test models of − 819 (C vs. T: OR = 0.691, P < 0.001; CC vs. TT: OR = 0.466, P < 0.001; CC + CT vs. TT: OR = 0.692, P < 0.001; and CC vs. CT + TT: OR = 0.557, P < 0.001), − 592 (C vs. A: OR = 0.779, P = 0.002; CC + AA vs. AA: OR = 0.713, P = 0.021; and CA vs. AA: OR = 0.716, P = 0.016), rs1518111 (G vs. A: OR = 0.738, P < 0.001; GG vs. AA: OR = 0.570, P < 0.001; GG + AG vs. AA: OR = 0.697, P < 0.001; GG vs. GA + AA: OR = 0.701, P < 0.001; and AG vs. GG: OR = 0.786, P = 0.004) and rs1554286 (C vs. T: OR = 0.582, P < 0.001; CC vs. TT: OR = 0.508, P < 0.001; CC + CT vs. TT: OR = 0.605, P < 0.001; CC vs. CT + TT: OR = 0.665, P = 0.012; and CT vs. TT: OR = 0.646, P = 0.001). However, we failed to find any association between − 1082 polymorphism and susceptibility of BD.

Conclusion

This meta-analysis demonstrated that the interleukin-10 -819, − 596, rs1518111 and rs1554286 polymorphisms could be responsible against BD susceptibility, and should probably be regarded as a protective factor for Behçet’s disease.

Cytokine Gene Polymorphisms in Saudi Patients With Atopic Dermatitis: A Case-Control Study

The cause of atopic dermatitis (AD) is multifactorial and a number of genes including cytokines have been involved. We genotyped 315 subjects for polymorphisms in TNF-α and TNF-β and IL-10 genes. Patients had significantly higher frequency of GA genotype of TNF-α (−308 G/A) than healthy controls. Patients with AD and controls had similar distribution of A and G alleles. Genotype AA was found in 7.11% of controls while completely absent in cases. The frequencies of genotypes GG and AA of TNF-β (+252 A/G) polymorphism were higher whereas the frequency of genotype GA was significantly lower in patients than the controls. The frequencies of genotypes GG and AA of IL-10 (1082 G/A) polymorphism were significantly increased whereas genotype GA was decreased in patients than the controls. It is concluded that TNF-α (−308 G/A), TNF-β (+252 A/G), and IL-10 (−1082 G/A) polymorphisms are linked with the susceptibility of AD in Saudis and can be a risk factor.

The significance and occurrence of TNF receptor polymorphisms in the Saudi population

Background and objective: On the basis that the inflammatory effects of TNF (tumour necrosis factor) are predominantly mediated through interaction with the TNF receptor-1 (TNFRSF1A), the current study was designed to establish the prevalence of the mutations, R92Q and P46L TNFRSF1A polymorphisms both in the general healthy Saudi population, and in Saudi patients carrying inflammatory diseases such as atherosclerosis or rheumatoid arthritis. We felt it important to report the frequency of the mutations, R92Q and P46L TNFRSF1A polymorphisms in healthy Saudi individuals, and those with inflammatory conditions, as well as to describe the pattern of immunological factors in individuals expressing R92Q or P46L TNFRSF1A. Patients and methods: We collected in PAX gene blood RNA tubes (for RT-PCR and sequencing) 500 blood samples from normal healthy individuals from the West and Center of Saudi Arabia, as well as 100 from patients with atherosclerosis, and 100 patients diagnosed with rheumatoid arthritis. All were screened for the levels of soluble TNF, C-reactive protein (CRP), interleukin6 (IL-6) and sTNFR1. In addition, they were screened for R92Q and P46L TNFRSF1A by RT-PCR. Moreover, phenotype and expression of peripheral blood mononuclear cells (PBMCs) was performed by flow cytometry (FACS). Results: Across 500 normal individuals, 8 (1.6%) expressed both R92Q and P46L mutations. By contrast, of the 100 patients in our study with atherosclerosis, 34% expressed both the R92Q and P46L mutations, whilst 42% of patients with rheumatoid arthritis expressed both mutations R92Q and P46L. No significant differences were observed between cell markers of normal individuals (CD3, 4, 8, 16, 56, 19, 25, ICAM-1, VLA-4 & l-selectin) and patients with atherosclerosis. There were significantly high values of cell markers in patients with rheumatoid arthritis compared with normal individuals both in terms of percentage and absolute counts (p < 0.05). Soluble IL-6 and sTNFR1 showed significant decreases in atherosclerosis and rheumatoid arthritis when compared with controls (p < 0.05). In addition, CRP and sTNF showed significant increases in the atherosclerosis and rheumatoid arthritis groups when compared to controls (p < 0.05). Conclusion: Our findings reasonably anticipate the presence of TRAPS disease (low penetrance mutations) amongst the Saudi population although further studies are needed to confirm these results.

Genetic Association of HLA-A*26, -A*31, and -B*51 with Behcet's Disease in Saudi Patients

BACKGROUND

HLA-B*51 has been universally associated with Behcet’s disease (BD) susceptibility, while different alleles of HLA-A have also been identified as independent BD susceptibility loci in various ethnic populations. The objective of this study was to investigate associations of HLA-A and -B alleles with BD in Saudi patients.

MATERIALS AND METHODS

Genotyping for HLA-A and HLA-B was performed using HLA genotyping kit (Lab type^(R) SSO) in 120 Saudi subjects, including 60 BD patients and 60 matched healthy controls.

RESULTS

Our results revealed that frequencies of HLA-A*26, -A*31, and -B*51 were significantly higher in BD patients than in controls, suggesting that HLA-A*26, -A*31, and -B*51 are associated with BD. The frequency of HLA-B*15 was significantly lower in BD patients than in controls. Stratification of genotyping results into active and nonactive forms of BD revealed that the frequency of HLA-A*31 was significantly higher in the nonactive form than in the active form of BD, while there was no significant difference in the distribution of other alleles between the two forms of BD.

CONCLUSION

This study suggests that HLA-A*26, -A*31, and -B*51 are associated with susceptibility risk to BD, while HLA-B*15 may be protective in Saudi patients. However, larger scale studies are needed to confirm these findings.

The association between pro- and anti-inflammatory cytokine polymorphisms and periventricular leukomalacia in newborns with hypoxic-ischemic encephalopathy

Background

Periventricular leukomalacia (PVL) is a frequent consequence of hypoxic-ischemic injury. Functional cytokine gene variants that result in altered production of inflammatory (tumor necrosis factor-alpha [TNF-α] and interleukin-1beta [IL-1β]) or anti-inflammatory (interleukin-10 [IL-10]) cytokines may modify disease processes, including PVL.

Objective

The aim of this study was to evaluate if there is a relationship between the two proinflammatory polymorphisms (TNF-α-1031T/C and IL-1β-511C/T) and the anti-inflammatory polymorphism IL-10-1082G/A and PVL risk in Brazilian newborns with and without this injury.

Materials and methods

A cross-sectional case-control study performed at the Neonatal Intensive Care Unit of the Children’s Hospital and Maternity of the São José do Rio Preto Medical School (FAMERP). Fifty preterm and term newborns were examined as index cases and 50 term newborns as controls, of both sexes for both groups. DNA was extracted from peripheral blood leukocytes, and the sites that encompassed the three polymorphisms were amplified by polymerase chain reaction-restriction fragment length polymorphism.

Results

Gestational age ranged from 25 to 39 weeks, in the case group, and in the control group it ranged from 38 to 42.5 weeks (P<0.0001). Statistically significant association was found between TNF-α-1031T/C high expression genotype TC (odds ratio [OR], 2.495; 95% confidence interval [CI], 1.10–5.63; P=0.043) as well as between genotypes (TC + CC) (OR, 2.471; 95% CI, 1.10–5.55; P=0.044) and risk of PVL. Statistically significant association was found between IL-1β-511C/T high expression genotypes (CT + TT) (OR, 23.120; 95% CI, 1.31–409.4; P=0.003) and risk of PVL. Statistically significant association between IL-10-1082G/A high expression genotype GG (OR, 0.07407; 95% CI, 0.02–0.34; P<0.0001) as well as between IL-10-1082G high expression allele (OR, 0.5098; 95% CI, 0.29–0.91; P=0,030) and PVL reduced risk was observed. There was a statistically significant association between TC/CT/GA genotype combination and the risk of PVL (OR, 6.469; 95% CI, 2.00–20.92; P=0.001).

Conclusion

There is evidence of an association between the polymorphisms TNF-α-1031T/C, IL-1β-511C/T, and IL-10-1082G/A and PVL risk in this Brazilian newborn population studied.