Evaluation of TLR9 expression on PBMCs and CpG ODN-TLR9 ligation on IFN-α production in SLE patients

Context: Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by autoreactive antibodies. Recent findings revealed the importance of innate immune responses, especially Toll-like receptors (TLRs) in the pathogenesis of SLE.

Objective: In this study, the level of TLR9 expression on peripheral blood mononuclear cells (PBMCs) was analyzed. The levels of produced IFN-α were also measured in supernatant of PBMCs from SLE patients and healthy controls after stimulation with CpG ODN2216 which is a plasmocytoid dendritic cell (pDC)-specific TLR9 ligand.

Materials and methods: TLR9 expression was analyzed by real-time polymerase chain reaction (PCR) and flow cytometry in 35 SLE patients and 38 healthy controls and IFN-α concentration was measured in supernatants using enzyme-linked immunosorbent assay (ELISA).

Results: The results showed that the TLR9 expression in the mRNA and the protein level was significantly higher in PBMCs from SLE patients. However, IFN-α concentration in patients and controls significantly increased in response to CpG stimulation but this increase was significantly higher in healthy controls compared with SLE patients. Our results do not show any association between taking hydroxychloroquine and reduction in IFN-α production in SLE patients.

Discussion and conclusions: Regarding the findings of the study, there is the possibility that TLR9 has played a role in SLE pathogenesis, and consequently it implies that TLRs can be considered to be the therapeutic targets for systemic autoimmunity. We may conclude that PBMCs in patients are functionally impaired in response to TLR ligation via innate response stimulating pathogen-associated molecular patterns (PAMPs).     

Matrix Metalloproteinase-9 rs17576 Gene Polymorphism and Behçet’s Disease: Is There an Association?

Background: Clinical studies have reported a significant association between matrix metalloproteinases (MMP), particularly (MMP-9), and inflammatory diseases including Behçet’s disease (BD).

Purpose: To study the relationship between MMP-9 rs17576 gene polymorphism and the development of BD, and its relation to disease activity among Egyptian patients.

Methods: A total of 100 BD patients and 100 healthy control volunteers were genotyped for MMP-9 rs17576 polymorphism with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), followed by the confirmation of our results in random subgroups using direct DNA sequencing technique.

Results: The frequency of the GG genotype and G allele was significantly higher in BD patients as compared to the normal controls (p = 0.011, OR 8.61; p = 0.03, OR 1.65, respectively). There was no significant association between the MMP-9 rs17576 polymorphism and the clinical outcomes of BD.

Conclusion: our study suggests a significant association of the MMP-9 rs17576 A/G polymorphism with increased risk of BD development in Egyptian patients.     

Safety of Toll-like receptor 9 agonists: a systematic review and meta-analysis

Context: The promising efficacy of Toll-like receptor 9 (TLR9) agonists for use against pathogenic infections, allergies, malignant neoplasms and autoimmunity have been demonstrated well in clinical studies, but the safety of TLR9 agonists is controversial.

Objective: In light of the safety concerns, we conducted a systematic review and meta-analysis of clinical studies of TLR9 agonists.

Methods: A systematic literature search was conducted. We selected studies in which the subjects were treated with a TLR9 agonist and in which the safety of the TLR9 agonist was monitored. We extracted data on adverse events (AEs) when available. A meta-analysis was performed to determine the commonest and clinical significant AEs observed in the controlled studies.

Results: Nine single-arm studies and 12 controlled studies met our selection criteria. Subjects treated with TLR9 agonists were at a higher risk of anemia (risk ratio [RR] 1.04, 95% confidence interval [CI]: 1.02–1.06), neutropenia (RR 1.16, 95% CI: 1.11–1.21), leukopenia (RR 1.16, 95% CI: 1.11–1.22), lymphopenia (RR 1.17, 95% CI: 1.10–1.25), thrombocytopenia (RR 1.20, 95% CI: 1.14–1.27), flu-like symptoms (RR 10.59, 95% CI: 3.66–30.66), diarrhea (RR 1.40, 95% CI: 1.18–1.67) and headache (RR 1.61, 95% CI: 1.26–2.06). Injection-site reactions, such as erythema, pain, pruritus and swelling, were mild to moderate. TLR9 agonist therapies have not been associated with clinically significant autoimmune diseases, and few deaths potentially attributable to TLR9 agonists have been reported.

Conclusion: The toxicity of TLR9 agonists is generally acceptable, except when the agonist is combined with immunosuppressive agents in patients with advanced non-small-cell lung cancer.     

Genetic Polymorphism (rs329498) in the Pellino-1 Gene as Possible Predisposal Factor for Systemic Lupus Erythematosus in a Chinese Population

Objective: The purpose of this study was to analyze the association of two single nucleotide polymorphisms (SNPs) in Peli-1 gene with systemic lupus erythematosus (SLE) in a Chinese population.

Methods: We conducted a case–control study and a total of 738 SLE patients and 827 healthy controls were finally recruited. Peli-1 rs329498 and rs10496105 polymorphisms were specified from genomic DNA using TaqMan genotyping assay on Fluidigm 192.24 system.

Results: Allele contrast showed the minor allele C was associated with decreased risk for SLE when compared with the A allele (OR = 0.851, 95% CI = 0.737–0.983, p = 0.028). Significant difference was observed in genotype distribution of rs329498 polymorphism between lupus nephritis (LN) patients and non-LN patients (χ² = 8.18, p = 0.017). Furthermore, we also found a decreased frequency of the minor allele C in LN patients (29.2%) than in non-LN patients (37.7%) (χ² = 8.67, p = 0.003). Moreover, a significant difference was also detected under a dominant model with regard to the distribution of genotype frequencies between LN patients and non-LN patients (CC + AC vs. AA: OR = 0.632, 95% CI = 0.451–0.884, p = 0.007). Clinical features analysis showed a significant difference in the distribution of genotypic frequencies between patients with malar rash and patients without this feature (χ² = 6.63, p = 0.036). Unfortunately, we failed to find any significant results between Peli-1 gene rs10496105 and SLE susceptibility.

Conclusions: Our observations suggested that Peli-1 gene polymorphism rs329498 might contribute to SLE susceptibility in Chinese Han Population. Likewise, the rs329498 SNP was also associated with the clinical features LN and malar rash in SLE patients.     

Association between Functional CYP2D6 Polymorphisms and Susceptibility to Autoimmune Diseases: A Meta-Analysis

Objective: This study aimed to explore whether functional CYP2D6 polymorphisms are associated with susceptibility to autoimmune diseases.

Methods: A meta-analysis was conducted on associations between autoimmune diseases and functional CYP2D6*4 1934 A/G and *3 polymorphisms and CYP2D6 phenotypes.

Results: Twelve studies with 1,472 patients and 3,328 controls were included. Autoimmune disease and the CYP2D6 1934 A allele were significantly associated in the overall group, consistent with the Hardy–Weinberg equilibrium (OR = 1.227, 95% CI = 1.071–1.406, p = 0.003); stratification by ethnicity indicated that the CYP2D6 1934 A allele and autoimmune diseases were associated in Caucasians (OR = 1.225, 95% CI = 1.010–1.485, p = 0.039). The CYP2D6*3 allele was also associated with autoimmune diseases in Caucasians (OR = 1.977, 95% CI = 1.125–3.472, p = 0.018). Stratified by autoimmune disease type revealed that the CYP2D6 1934 AA genotype was associated with systemic lupus erythematosus (SLE; OR = 2.007, 95% CI = 1.170–3.442, p = 0.011) and ankylosing spondylitis (AS; OR = 2.317, 95% CI = 1.422–3.774, p = 0.001). The CYP2D6 PM+IM phenotype was significantly associated with autoimmune diseases in Caucasians (OR = 1.526, 95% CI = 1.038–2.246, p = 0.032) and with SLE (OR = 1.778, 95% CI = 1.249–2.532, p = 0.001).

Conclusions: This meta-analysis indicates that CYP2D6*4 and *3 polymorphisms and the CYP2D6 phenotype are associated with susceptibility to autoimmune diseases in Caucasians; particularly, the CYP2D6*4 polymorphism and CYP2D6 PM+IM phenotype are risk factors for SLE development.     

Association between IL-33 Gene Polymorphisms (rs1929992, rs7044343) and Systemic Lupus Erythematosus in a Chinese Han Population

Objective: Interleukin-33 (IL-33) is a member of the IL-1 family, and previous studies found the single-nucleotide polymorphisms (SNPs) in the IL-33 gene was related to susceptibility to autoimmune diseases, including rheumatoid arthritis, ankylosing spondylitis and Behcet’s disease. To date, no study has discussed the potential association between IL-33 gene polymorphisms and systemic lupus erythematosus (SLE).

Methods: We conducted a case-control study including 371 SLE patients and 408 healthy controls to investigate the correlation between the SNPs of IL-33 gene (rs1929992, rs7044343) and SLE in a Chinese Han population.

Results: There was significantly lower expression of allele G for rs1929992 in SLE patients than that in controls (G versus A, P = 0.012, OR = 1.310, 95% CI: 1.060–1.624 after adjustment with sex). Similarly, genotype GG was associated with the susceptibility to SLE as compared with the AA genotype (P = 0.017, OR = 1.714, 95% CI: 1.101–2.669 after adjustment with sex). We also found statistical significance in the dominant model (GG+GA versus AA, P = 0.017, OR = 1.481, 95% CI: 1.074–2.044 after adjustment with sex). However, we found no strong evidence for the association of IL-33 rs7044343 polymorphism with SLE. Moreover, association studies were performed on the relationship between the IL-33 gene polymorphisms and lupus nephritis as well as nine clinical features of SLE, but there was no significant association regarding the distribution of allele and genotype frequencies between SLE patients positive and negative for the presence of sub-phenotypes.

Conclusion: Our findings indicate that IL-33 rs1929992 polymorphism may be a potential biomarker for susceptibility to SLE.     

Rheumatic Disease Autoantibodies in Autoimmune Liver Diseases

Background: Autoimmune liver diseases (ALDs) are known to be associated with systemic autoimmune rheumatic diseases (SARDs) and their autoantibodies. We aimed to study the prevalence of SARDs and related autoantibodies, as well as their prognostic implications in a group of patients with ALDs.

Methods: This was a cross-sectional study. Sixty patients with ALDs (38.3% with autoimmune hepatitis; 11.7% with primary biliary cirrhosis; 25% with primary sclerosing cholangitis and 25% with overlap syndrome) were studied for the presence of SARDs and their autoantibodies.

Results: There was autoimmune rheumatic disease in 20% of the studied sample. Systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA) were the commonest (11.6% and 5%, respectively). Antinuclear antibodies (ANAs) were present in 35% of the patients, followed by anti-Ro (20.0%); anti-nucleosome (18.3%); rheumatoid factor (10%) anti-CCP (8.3%); anti-RNP (8.3%); anti-ds-DNA (6.6%); anti-La (3.3%); anti-Sm (3.3%), anti-ribosomal P (3.3%). Anti-Ro (p = 0.0004), anti-La (p = 0.03), anti-RNP (p = 0.04) and anti-Sm (p = 0.03) were commonly found in patients with SARD, but not anti-DNA, anti-nucleosome and anti-ribosomal P. No differences were found in liver function tests regarding to the presence of autoantibodies.

Conclusions: There was a high prevalence of SARD and their autoantibodies in ALD patients. Anti-Ro, anti-La, anti-RNP and anti-Sm positivity points to an association with systemic autoimmune rheumatic diseases. The presence of autoantibodies was not related to liver function tests.     

Immune Profiling of T Cells Infiltrating Vitreous Humor in Tubercular Uveitis

Purpose: To assess cellular composition and local cytokine response in vitreous humor of tubercular uveitis.

Methods: Cells were collected from vitreous cassettes and peripheral blood of 8 tubercular uveitis and 5 control subjects, undergoing vitrectomy and analyzed by flow cytometry for cellular composition, activation status, proinflammatory cytokine expression, and uptake of TLR9 ligand, CpG ODN 2216.

Results: CD3 + T cells with equal proportion of CD4+ and CD8 + T cells formed major fraction of infiltrating cells. The vitreous humor showed higher expression of recent activation marker, CD69, and proinflammatory cytokines, IFN-γ and IL-17A, in CD4 + T cells as compared to peripheral blood. Lastly, intraocular CD4 + T cells showed reduced uptake of ODN 2216 than peripheral blood.

Conclusions: Our results indicate that local antigenic stimuli trigger T cell infiltration and activation of CD4 + T cells that are hyporesponsive to TLR9 stimulation. These infiltrating T cells might be responsible in further aggravating ocular inflammation.     

IL12 Gene Polymorphism in Association with Hepatocellular Carcinoma in HCV-infected Egyptian Patients

Background: Hepatocellular carcinoma has been recorded the commonest cancer in Egypt. This increasing incidence may be attributed to the high prevalence of hepatitis C virus with its complications, so this study aimed to investigate the association between the potentially functional polymorphisms of IL12A and IL12B genes as a risk factor of development of hepatocellular carcinoma (HCC) on top of hepatitis C virus (HCV) infection in an Egyptian population.

Materials and methods: We genotyped two loci of IL12 which were rs568408 (3’UTR G>A) for IL12A and rs3212227 (3’UTR A>C) for IL12B in 78 patients with HCC on top of chronic HCV infection. In addition, 64 cancer-free chronic HCV patients were studied, besides 92 healthy subjects who were included as control.

Results: Study of rs568408 (G>A) gene polymorphism showed that the A allele is higher while the G allele is lower in HCC cases than cancer-free chronic HCV patients (p = 0.006*). The A-containing genotypes AG and (AG+AA) were higher while the GG was lower (p = 0.009* and p = 0.005*), respectively. The study of the rs3212227 (A>C) polymorphism showed neither statistically significant differences between the C and A allele (p = 0.2) nor between CC, AC, or AC+CC in HCC cases and cancer-free chronic HCV patients (p = 0.7, p = 0.2, and p = 0.29), respectively.

Conclusion: Our findings showed that IL12A rs568408 (G>A) polymorphism may contribute to the risk of HCC on top of chronic HCV infection, whereas that of IL12B rs3212227 (A>C) do not.     

Distribution of polymorphisms in the CYP2C9 gene and CYP2C19/CYP2C9 haplotypes among Venezuelan populations

Background: Polymorphisms with decreased enzyme activity of their gene products have been reported in region CYP2C with population variations in haplotype structure.

Aim: To estimate the allelic and genotypic frequencies of variants CYP2C9*2 and CYP2C9*3 and of CYP2C9/CYP2C19 haplotypes in Venezuelan populations.

Subjects and methods: Six hundred and thirty-four individuals from nine admixed populations (AP) and the Warao indigenous group were studied. Allelic frequencies, linkage disequilibrium and genetic distances for haplotypes were calculated and compared within Venezuela and with data available in the literature.

Results: Heterogeneity in the distribution of CYP2C9 alleles and CYP2C9/CYP2C19 haplotypes among the AP and the Warao was observed. The joint frequency of haplotypes, with at least one non-functional variant, shows values in AP between 21–41%, while in Warao it reaches 5%. The haplotype that includes the Asian and rare Latin America CYP2C19*3 allele was detected in most AP and in Warao. Pairwise Fst values showed that the Warao was an outlier compared with the AP, while these are closer to European-derived populations. No significant correlation was found between haplotype frequencies and admixture.

Conclusions: These results support the need to understand the distribution of genomic biomarkers related to the metabolism of drugs, for planning national public health strategies.     

Lack of Association between MYO9B Gene Polymorphisms and Susceptibility to Coeliac Disease in Caucasians: Evidence from a Meta-Analysis

Objective: Coeliac disease (CD) is a complex disorder influenced by environmental and genetic factors. Recently, a number of studies reported MYO9B gene is associated with CD, but the results are controversial. The aim of this study is to clarify this dispute by means of a meta-analysis.

Methods: The databases of PubMed, Web of Science, and Embase updated to August 2015 were retrieved. Crude odds ratio (OR) and corresponding 95% confidence interval (95%CI) as effect size were calculated by fixed or random effect model according to the heterogeneity.

Results: A total of 8 studies including 2272 cases and 5419 controls were enrolled in this meta-analysis. There was no significant association both in allele and genotype comparisons between the MYO9B (rs2305764, rs2305767, rs1457092) polymorphism and CD in Caucasian populations. No publication bias was detected in this meta-analysis.

Conclusions: This meta-analysis indicates that MYO9B gene polymorphisms might be not associated with CD susceptibility in Caucasians. Further studies are still needed for definitive conclusions.     

Mannose-Binding Lectin Deficiency in Brazilian Patients with Spondyloarthritis

Background: Infections are usually involved in the pathogenesis of spondyloarthritis (SpA). Mannose-binding lectin (MBL) is a component of the innate immune system with an important role in microbial defense.

Objective: To study the prevalence of MBL deficiency in SpA patients as well as its influence in the clinical profile of these diseases.

Methods: We studied 89 SpA patients and 89 healthy individuals, paired for age and gender. MBL serum levels were measured by ELISA test. Individuals with levels ≤100 ng/mL were considered deficient. SpA patients had determination of Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Ankylosing Spondylitis Disease Activity Score (ASDAS)-CRP, Bath Ankylosing Spondylitis Functional Index (BASFI), C reactive protein (CRP), erythrocyte sedimentation rate (ESR), and review of their clinical profile.

Results: SpA patients had MBL levels ranging from 100 to 4100 ng/mL (median = 375 ng/mL); controls levels ranged from 100 to 4703 ng/mL (median = 1204 ng/mL; p < 0.0001). The prevalence of MBL deficiency was 27/89 (30.3%) in SpA patients and 12/89 (13.5%) in controls, with p = 0.01; OR = 2.5 (95% IC = 1.2–5.3). No association/correlation was found between MBL levels with BASDAI, BASFI, age at disease onset, ASDAS-CRP, ESR, CRP, presence of uveitis, HLAB27, peripheral arthritis, or SpA subtype (all p = NS).

Conclusion: MBL levels may be linked with the occurrence of SpA but do not influence its phenotype.     

Association between CD226 polymorphism and soluble levels in rheumatoid arthritis: Relationship with clinical activity

Objective: To study the relation between CD226 rs763361 gene polymorphism and CD226 serum level and to evaluate their role in susceptibility and disease activity of RA in a cohort of Egyptian individuals.

Methods: The serum level of CD226 was measured using a suitable ELISA kit and the CD226 rs763361 gene polymorphism was typed by PCR-RFLP for 112 RA patients and 100 healthy controls.

Results: Significant association with RA was found with CD226 T allele (OR (95%CI) = 1.6 (1.04–2.4), P = 0.032), and higher CD226 serum level (P = 0.001). Higher CD226 levels were associated with higher ESR values (P = 0.035), positive CRP (0.048), increased number of tender joints (P = 0.045), and higher DAS score (P = 0.035). Serum CD226 is an independent risk factor for the prediction of RA (P = 0.001). No correlations were found between the serum level of CD226 and different CD226 genotypes and also between them and RA activity grades.

Conclusion: The CD226 T allele may be susceptibility risk factors for the development of RA and the higher serum level of CD226 may be involved in the pathogenesis of RA in Egyptian patients. The serum level of CD226 and not CD226 genotypes could be considered as an independent risk factor for the prediction of RA within healthy individuals and also for RA disease activity.     

Improving B-cell depletion in systemic lupus erythematosus and rheumatoid arthritis

Introduction: Rituximab-based B-cell depletion (BCD) therapy is effective in refractory rheumatoid arthritis (RA) and although used to treat patients with refractory systemic lupus erythematosus (SLE) in routine clinical practice, rituximab failed to meet the primary endpoints in two large randomised controlled trials (RCTs) of non-renal (EXPLORER) and renal (LUNAR) SLE.

Areas covered: We review how BCD could be improved to achieve better clinical responses in RA and SLE. Insights into the variability in clinical response to BCD in RA and SLE may help develop new therapeutic strategies. To this end, a literature search was performed using the following terms: rheumatoid arthritis, systemic erythematosus lupus, rituximab and B-cell depletion.

Expert commentary: Poor trial design may have, at least partly, contributed to the apparent lack of response to BCD in the two RCTs of patients with SLE. Enhanced B-cell depletion and/or sequential therapy with belimumab may improve clinical response at least in some patients with SLE     

Development and psychometric evaluation of a condom use self-efficacy measure in Spanish and English

Background: Condom self-efficacy is an important construct for HIV/STI prevention and intervention. A psychometrically sound measure of the self-efficacy for using condoms that has been designed for Hispanic women to respond in Spanish or English is needed.

Objectives: The goal of this study was to develop and evaluate a brief self-report measure of condom use self-efficacy.

Methods: We developed a 15-item measure of condom use self-efficacy based on expert knowledge of measurement and HIV/STI prevention with Hispanic women using a translation-back translation approach. Participants were 320 Hispanic women from the Southeastern US.

Results: Internal consistency of the full measure was 92. A short form of the instrument with a subset of five items also had acceptable internal consistency, alpha = .80, and was significantly correlated with the full scale, r_s = .93, p < .001. A single latent factor explained 9–48% of the variation in these items. Evidence of construct validity of the short form was provided by correlations of the scale with two self-report measures of condom use: r_s = .34** with condom use, r_s = .37** with condom use during vaginal sex.

Conclusions: Either the full measure or the five-item measure could be used in studies where condom use is an important behavioral outcome, such as evaluating prevention interventions, with Hispanic women. Future studies should examine the performance of this measure with other groups, including Hispanic men and members of other ethnic and language groups.     

Therapeutic targeting of Toll-like receptors: a review of Toll-like receptors and their signaling pathways in psoriasis

Introduction: Expression of various Toll-like receptors (TLR) in keratinocytes (KCs) has offered new insights into the pathogenesis of psoriasis. When plasmacytoid dendritic cells (pDCs) are scarce in established psoriatic lesions, KCs take the responsibility to secrete IFN type 1 through TLR9 activation. Antagonists of TLR7 and TLR8 and anti-IL-12/IL-23 substances have shown promising results in treating psoriasis.

Areas covered: References in this study were extracted from Scopus, PubMed and Embase databases by the search term: (‘Toll-Like Receptors’ OR ‘TLR’) AND (‘Psoriasis’ OR ‘Arthritis, Psoriatic’ OR ‘PsA’).

Expert commentary: As the prevailing cell type, KCs play a major role in the maintenance of psoriatic lesions. By specific upregulation of IL-36 R, KCs can start the IL-23/IL-12 axis, leading to production of major culprits of psoriatic phenotype IL-17 and IL-22. Targeting IL-36 R could be considered as a new therapeutic target to eliminate cutaneous manifestations of psoriasis.     

PTPN22 Single-Nucleotide Polymorphisms in Iranian Patients with Type 1 Diabetes Mellitus

Background: PTPN22 plays a crucial role in regulating the function of various cells of the immune system, particularly T cells. Polymorphisms of the PTPN22 gene have been associated with many autoimmune diseases, including type 1 diabetes (T1D) which is a T-cell-mediated disease.

Objective: The present study was aimed at genotyping of an Iranian population for five polymorphisms of the PTPN22 gene.

Methods: The study population consisted of 99 T1D patients and 100 healthy controls. We genotyped five single-nucleotide polymorphisms (SNPs) (rs12760457, rs1310182, rs1217414, rs33996649, and rs2476601) of the PTPN22 gene.

Results: Regarding the variant rs2476601, genotypes AG and GG were increased and decreased in T1D patients compared with controls, respectively. Further, alleles G and A of this SNP were found to be decreased and increased in T1D patients, respectively (p value = 0.001). However, T1D and control groups did not differ on genotype distribution or allele frequency for other investigated SNPs.

Conclusions: The PTPN22 rs2476601 minor allele (A) was associated with T1D in Iran, accounting for its pathophysiology in autoimmune diseases.