Association between TH2 Cytokine Gene Polymorphisms and Risk of Bullous Pemphigoid.

BACKGROUND: T-helper 2 (Th2)-associated cytokines are involved in the pathogenesis of bullous pemphigoid (BP), an autoimmune skin disease. Increased expression of Th2 cytokines such as interleukin-4 (IL-4), IL-5, IL-6, IL-10, and IL-13 have been observed in serum, skin biopsies and/or blister fluid. This study aimed to uncover a possible association between Th2 cytokine genetic variations and susceptibility to BP. METHODS: In a cohort study, blood samples of BP patients and controls were obtained and variations in IL-4 (rs2243250 and rs2070874), IL-4R (rs1805010), IL-5 (rs2069812), IL-6 (rs1800795), IL-10 (rs1800896, rs1800871, and rs1800872), and IL-13 (rs1800925 and rs20541) were genotyped by PCR-RFLP assays. Furthermore, quantitative expression levels of IL-13 gene were evaluated by real-time RT-PCR analysis. RESULTS: Among the studied variations, a significantly higher frequency of the C-allele was observed in IL-13 gene variation (rs1800925) in the healthy individuals than BP patients. This may indicate a protective effect of C-allele on predisposition to BP. Considering individuals carrying polymorphic genotypes compared to wild genotype, the minor G-allele of IL-4R rs1805010 and A-allele of IL-13 rs20541 had a promotive and protective effect, respectively, on predisposing to the development of BP. No significant difference in IL-13 mRNA expression was detected between BP patients and healthy individuals. CONCLUSIONS: Our results indicate that IL-13 rs1800925 variation may be a protective genetic marker for the development of BP. Given this preventive effect against BP, therapeutic strategies could potentially be developed interfering with the functions of IL-13 cytokine, which seems to be integral in the pathogenesis of eosinophilic inflammatory disorders, such as BP.

The MCP-1 rs1024611 and MTHFR rs1801133 gene variations and expressions in alopecia areata: A pilot study.

BACKGROUND: Monocyte chemoattractant protein-1 (MCP-1) is highly expressed by lymphocytes at skin sites affected by alopecia areata (AA). Variations in MCP-1 as well as in methylene-tetrahydrofolate reductase (MTHFR), a key enzyme related to many inflammatory pathologies, have been associated with several autoimmune disorders. This study was designed to test a possible association between MCP-1 and MTHFR variations and altered expression of their genes and the risk of AA. METHODS: Blood samples of patients (60) suffering from AA as well as healthy subjects (60) were collected. Gene expression levels of MCP-1 and MTHFR were evaluated by real-time reverse-transcription polymerase chain reaction analysis. Moreover, MCP-1 rs1024611 (A-2518G) and MTHFR rs1801133 (C677T) polymorphisms were genotyped by using polymerase chain reaction-restriction fragment length polymorphism assays. RESULTS: In contrast to MCP-1, the MTHFR gene expression was found to be significantly higher in patients than in controls. Further stratification of the patients revealed that polymorphic genotypes in MCP-1 (AG + GG) and MTHFR (CT + TT) could significantly alter gene expression levels. Elevation of MCP-1 expression was significantly associated with the total number of variant MCP-1 and MTHFR alleles. However, no statistically significant difference was noticed in the genotypic distribution of MCP-1 and MTHFR variations between patients and controls. CONCLUSION: In summary, despite MCP-1 rs1024611 and MTHFR rs1801133 variations are not associated with AA risk, they may implicate the disease pathogenesis by influencing MCP-1 activity.

TH17/IL23 cytokine gene polymorphisms in bullous pemphigoid.

BACKGROUND: TH17/IL-23 immune axis is considered to be involved in the pathogenesis of autoimmune and chronic inflammatory diseases. Bullous pemphigoid (BP) is the most frequent autoimmune blistering disease, characterized by the presence of autoantibodies against the components of the dermal-epidermal junction. Animal studies and characterization of patient samples point toward a contribution of TH17 cells in BP pathogenesis. However, genetic polymorphisms in the genes of TH17/IL-23 cytokines have not yet been well investigated in BP. METHODS: Detection of polymorphisms in IL-17A (rs2275913 and rs3819025), IL-17F (rs2397084 and rs763780), IL-17RA (rs2229151), and IL-23R (rs2201841, rs7530511, rs11209026, and rs10889677) genes were performed following the collection of blood samples and DNA extraction from BP patients and controls. Gene expression of IL-23R was determined by quantitative RT-PCR analysis. RESULTS: The prevalence of IL-23R rs7530511 genotypes and alleles, as well as IL-23R rs2201841 alleles, is significantly different between the BP patients and controls. While the minor C-allele of IL-23R rs7530511 is highly present in the patients, the G-allele distribution of IL-23R rs2201841 is significantly more prevalent in the control individuals compared to the BP patients. Genotypes and alleles of other SNPs in IL-17A, IL-17F, and IL-17RA were similarly distributed in patients and controls. CONCLUSIONS: No alteration was found in the gene expression between wild and polymorphic genotypes of IL-23R (rs2201841 and rs7530511) variations, indicating they do not contribute to altering the levels of gene expression in blood. In summary, our data show that the alleles of two SNPs in IL-23R rs2201841 and rs7530511 are associated with BP.

IL12B and IL23R polymorphisms are associated with alopecia areata.

Alopecia areata is an autoimmune disease in which activation of autoreactive T cells and inflammatory immune signals target the hair follicles autoantigens. Although cytokines are involved in regulating autoimmune inflammation, the specific involvement of these molecules in the pathogenesis of alopecia areata has been remained unsettled. Here, a possible influence of IL12B, IL17A, and IL23R variations on susceptibility to alopecia areata in Iranian patients was investigated. Genotyping of IL12B (rs3212227), IL17A (rs2275913), and IL23R (rs10889677) variants were performed by extracting genomic DNA from patients and controls. Gene expression was analyzed by real-time RT-PCR. The frequency of IL12B and IL23R gene polymorphisms is significantly higher in the patients than controls, while no significant difference was found for IL17A. Stratification of the patients with respect to age at disease onset indicated that CC genotype of IL12B (rs3212227) and AA genotype of IL23R (rs10889677) gene polymorphisms are significantly associated with late-onset alopecia areata disease. In contrast to IL17A and IL23R, IL12B gene expression levels elevated in patients to that of controls, but genotypes had no effect on levels of gene expression. Overall, our data confirmed that the IL12B and IL23R polymorphisms are associated with the risk to develop alopecia areata in our population.

Overlapping and Distinct FAS/FASLG Gene Polymorphisms in Alopecia Areata in an Iranian Population.

Alopecia areata (AA) is considered to have a multifactorial etiology and polymorphisms in certain genes have been shown to be associated with AA. Although several reports have investigated the effect of FAS/FAS ligand (FASLG) gene variations with predisposing to AA, genetic association of disease, however, varies among different ethnicities and no data have so far been reported in Iranian population. The present study aimed to uncover a possible association between variations in FAS/FASLG genes and AA. Genomic DNA was extracted from all samples and the SNPs of FAS (rs1800682) and FASLG (rs5030772) genes were genotyped in AA patients and controls. In addition, gene expression of FAS/FASLG was assessed by RT-PCR. Regarding FASLG, the frequency of the G-allele was significantly higher in the patients compared to the controls, indicating that the G-allele at this locus could be a risk for developing AA. In contrast, no association was found for rs1800682 (FAS) with AA. Similarly, compared to controls, FASLG gene expression was upregulated. While no association between clinical-demographic characteristics of the AA patients and their genotypes in FAS/FASL variations was observed, multivariate regression analysis indicated a correlation between the incidence of AA disease and its familial history as well as AG/GG genotypes of FASLG (rs5030772). In conclusion, our data indicate an association between FASLG rs5030772 variation and AA. However, previously reported the association of FAS rs1800682 polymorphism with AA was not observed here. These findings highlight overlapping and distinct genetic polymorphisms in an Iranian cohort which might influence the susceptibility to AA.

Proinflammatory Cytokine Gene Polymorphisms in Bullous Pemphigoid.

Bullous pemphigoid (BP) is a rare autoimmune skin blistering disease, characterized by the presence of autoantibodies against hemidesmosomal autoantigens. Cytokine expression is altered in BP patients, and several of these differently expressed cytokines, including IL-1α, IL-1ß, IL-8, and TNF-α, contribute to disease pathogenesis. Since genetic polymorphisms in the genes of these cytokines might be implicated in susceptibility to BP disease, we aimed at testing this implication in susceptibility to BP in an Iranian cohort. Blood samples were collected from the subjects and genomic DNA was extracted. To detect the single nucleotide polymorphisms (SNPs), IL-1α (rs1800587), IL-1ß (rs1143627, rs16944, rs1143634), IL-8 (rs4073), and TNF-α (rs1799964, rs1800630, rs1799724, and rs361525) genes were genotyped in BP patients and healthy controls as well as IL-8 (rs4073) in pemphigus vulgaris (PV) patients. Quantitative gene expression was evaluated by RT-PCR analysis. A significant difference was observed in the distribution of genotypes or alleles of IL-8 SNP between the BP patients and controls. The A-allele of IL-8 SNP is significantly more prevalent in the control individuals compared to the BP patient. To further validate this observation, we included PV patients as an additional control. Again, the A-allele of IL-8 SNP is significantly more prevalent in the PV compared to the BP patients. While we observed a trend toward significant differences regarding alleles of TNF-α rs1799724 as well as alleles of TNF-α rs1799964, this difference was, however, not evident after correction for multiple analysis. There was no significant difference in all other studied SNPs. In contrast to IL-1α, IL-1ß, and TNF-α, IL-8 gene expression levels were significantly higher in the patients than that of controls. The minor allele in IL-8 SNP might play a protective role in susceptibility to BP in Iranian patients. Although higher expression levels of IL-8 gene was found in the patients compared with healthy controls, these levels, however, suggest no association with the examined polymorphism. Moreover, further investigation revealed an elevation in gene expression between wild and polymorphic genotypes of IL-1α rs1800587 and TNF-α rs361525 in the patient group and these SNPs are therefore associated with altering the levels of gene expression.

Genetic variant association of PTPN22, CTLA4, IL2RA, as well as HLA frequencies in susceptibility to alopecia areata.

Alopecia areata (AA) is characterized by a genetically complex inheritance. HLA frequencies, as well as the single nucleotide polymorphism (SNP) in PTPN22, CTLA4, and IL2RA genes, have been described to be associated with AA susceptibility. So far, no independent replication of these studies has been reported, and no data exist on a possible association between AA disease and these SNPs or influence of HLA frequencies in Iranian population. A possible association between HLA-DRB1*11 alleles as well as a single variation in PTPN22, CTLA4, and IL2RA genes and patchy AA disease have been investigated in a cohort from Iran. Patient and control subjects were genotyped for PTPN22 (rs2476601), CTLA4 (rs3087243), and IL2RA (rs3118470) variations as well as HLA frequencies. Gene expression levels were analyzed by real-time RT-PCR. In contrast to PTPN22 and CTLA4 gene polymorphisms, a significant association was found between IL2RA SNP and susceptibility to AA in Iranian cohort. While gene expression levels of IL2RA and PTPN22 were higher in the patients than that of controls, CTLA4 expression levels found significantly lower in the patients. Despite a significant association between AA and HLA-DRB1*11 frequencies, the presence of DRB1*11 is not associated with PTPN22, CTLA4, or IL2RA gene SNPs. Although the minor allele in IL2RA SNP can be a significant determinant of AA disease development in Iranian population, reported an association between the PTPN22 and CTLA4 variations was not confirmed by our study. Furthermore, these genetic risk factors might act independently from HLA alleles.

TNF-α -308G/A gene polymorphism in bullous pemphigoid and alopecia areata.

BACKGROUND: TNF-α -308G/A polymorphism has been investigated in few studies for an association with susceptibility to bullous pemphigoid (BP) and alopecia areata (AA). Yet, these findings had so far not been independently replicated, and no data on a possible association of TNFα -308G/A polymorphism with these diseases in Iranian population were available. OBJECTIVES: In the present study, a possible effect of TNF-α -308G/A variation on susceptibility to BP or AA disease was evaluated. METHODS: Genomic DNA was extracted from the blood of the patients with BP and AA as well as control subjects which genotyped for the TNF-α -308 G/A polymorphism. TNF-α gene expression levels were analyzed by real-time RT-PCR. RESULTS: No association was observed between the TNF-α -308 G/A variation and susceptibility to BP or AA diseases in our Iranian cohort. In contrast to AA patients, expression of TNF-α gene was significantly higher in BP patients compared to control group. TNF-α gene was found to be similarly expressed in mutant and wild-type genotypes. CONCLUSIONS: TNF-α -308G/A polymorphism is not associated with the risk to develop of BP and AA in our Iranian cohort. Furthermore, this polymorphism is contributed to altering the levels of gene expression in BP disease.

Emphasizing the role of surface chemistry on hydrophobicity and cell adhesion behavior of polydimethylsiloxane/TiO2 nanocomposite films.

Improving the bioinertness of materials is of great importance for developing biomedical devices that contact human tissues. The main goal of this study was to establish correlations among surface morphology, roughness and chemistry with hydrophobicity and cell adhesion in polydimethylsiloxane (PDMS) nanocomposites loaded with titanium dioxide (TiO2) nanoparticles. Firstly, wettability results showed that the nanocomposite loaded with 30 wt.% of TiO2 exhibited a superhydrophobic behavior; however, the morphology and roughness analysis proved that there was no discernible difference between the surface structures of samples loaded with 20 and 30 wt.% of nanoparticles. Both cell culture and MTT assay experiments showed that, despite the similarity between the surface structures, the sample loaded with 30 wt.% nanoparticles exhibits the greatest reduction in the cell viability (80%) as compared with the pure PDMS film. According to the X-ray photoelectron spectroscopy results, the remarkable reduction in cell viability of the superhydrophobic sample could be majorly attributed to the role of surface chemistry. The obtained results emphasize the importance of adjusting the surface properties especially surface chemistry to gain the optimum cell adhesion behavior.