Association study on IL4, IL13 and IL4RA polymorphisms in mite-sensitized persistent allergic rhinitis in a Chinese population

Polymorphisms and AR: A Systematic Review and Meta-Analyses

Background: Allergic rhinitis (AR) is an especially common disorder associated with both environmental and genetic factors, and a lot of researchers have attempted to find polymorphisms which predisposed to the disease. We conducted a meta-analysis of the most frequently researched polymorphisms to find those genes which may be susceptible to AR and then may be of value in diagnosis.

Methods: Pubmed and China National Knowledge Infrastructure (CNKI) databases were searched to screen out eligible studies focusing on the correlation between polymorphisms and AR susceptibility, and then polymorphisms cited in at least 3 studies were selected.

Results: The 142 papers originally selected cited 78 genes. Twelve genes (coinciding with 23 polymorphisms) were reported in more than three papers. Twenty-three polymorphisms were involved in the meta-analysis. Among the 23 polymorphisms, only 4 were found to be related to the risk of AR: IL-13 rs20541, CTLA-4 rs11571302, IL-4R RS1801275 and ACE (I/D). The remaining 19 of the 23 polymorphisms were not associated with AR.

Conclusion: We found polymorphisms that could be used for AR diagnosing and those that were unrelated to AR. This may be the first step in detecting polymorphic combinations susceptible to AR (IL-13 RS20541, CTLA-4 RS11571302, IL-4R RS1801275 and ACE (I/D). In addition, our results may improve AR diagnosis and contribute to the intensive study of AR.

Atopy as Immune Dysregulation: Offender Genes and Targets

Allergic diseases are a heterogeneous group of disorders resulting from exaggerated type 2 inflammation. Although typically viewed as polygenic multifactorial disorders caused by the interaction of several genes with the environment, we have come to appreciate that allergic diseases can also be caused by monogenic variants affecting the immune system and the skin epithelial barrier. Through a myriad of genetic association studies and high-throughput sequencing tools, many monogenic and polygenic culprits of allergic diseases have been described. Identifying the genetic causes of atopy has shaped our understanding of how these conditions occur and how they may be treated and even prevented. Precision diagnostic tools and therapies that address the specific molecular pathways implicated in allergic inflammation provide exciting opportunities to improve our care for patients across the field of allergy and immunology. Here, we highlight offender genes implicated in polygenic and monogenic allergic diseases and list targeted therapeutic approaches that address these disrupted pathways.

Serum level and clinical significance of vitamin E in pregnant women with allergic rhinitis

BACKGROUND

Allergic rhinitis is a frequent disorder during pregnancy, while in children it is triggered by significantly lower serum vitamin E level. This research aimed to investigate whether serum vitamin E level exhibited clinical significance in pregnant women with allergic rhinitis.

METHODS

In this study, 37 pregnant women with allergic rhinitis and 35 healthy pregnant women were recruited. Allergic rhinitis severity was analyzed by the Total Nasal Symptom Score (TNSS) questionnaire. Blood samples were collected to evaluate serum vitamin E, interleukin (IL), and total IgE levels.

RESULTS

In pregnant women with allergic rhinitis, serum level of vitamin E was significantly lower than in healthy pregnant women. Serum vitamin E level in pregnant women with allergic rhinitis showed a negative correlation with TNSS, IL-13, IL-4, and total IgE levels.

CONCLUSION

In conclusion, this research has demonstrated that pregnant women with allergic rhinitis showed significantly lower serum level of vitamin E. The decreased vitamin E showed a correlation with the pathogenesis of allergic rhinitis in pregnant women.

Genetics and Epigenetics in Allergic Rhinitis

The pathogenesis of allergic rhinitis is associated with genetic, environmental, and epigenetic factors. Genotyping of single nucleotide polymorphisms (SNPs) is an advanced technique in the field of molecular genetics that is closely correlated with genome-wide association studies (GWASs) in large population groups with allergic diseases. Many recent studies have paid attention to the role of epigenetics, including alteration of DNA methylation, histone acetylation, and miRNA levels in the pathogenesis of allergic rhinitis. In this review article, genetics and epigenetics of allergic rhinitis, including information regarding functions and significance of previously known and newly-discovered genes, are summarized. Directions for future genetic and epigenetic studies of allergic rhinitis are also proposed.

Atopy in Kashmir-validation from a case control study with respect to IgE and Interleukin genes

OBJECTIVES

Increased levels of serum Immunoglobulin-E (IgE) and different genetic variants of cytokines are common biochemical manifestation in Allergy. The current study was aimed to study the association of IgE and different variants of Interleukin-4 (IL-4), and Interleukin-13 (IL-13) genes with different kind of allergies.

METHODS

A pre-tested questionnaire was used to collect all the dietary, life style and clinical details by a trained staff. A blood sample of 2 ml each was collected in coagulated and anti-coagulated vials. DNA and serum samples were extracted and stored until further use. Serum IgE were estimated by ELISA while as the genotypic analysis was done by PCR-RFLP methods.

RESULTS

Statistically a significant difference of serum IgE levels were observed among cases and controls (P < 0.05). The observed significant difference of serum IgE levels were retained among subjects who also harboured variant genotypes of IL-4 and IL-13 genes (P < 0.05). Additionally, the above genetic variants significantly modified the risk of allergy when stratification was done based on various clinical characteristics.

CONCLUSION

Our study suggests that increased IgE levels and in association with variant forms of IL-4 and IL-13 genes are significantly associated with different types of allergies in study population.

Interleukin 4 and Interleukin 4 receptor alpha gene variants and risk of atopy - A case control study based assessment

INTRODUCTION

IL4 pathway is known to upregulate IgE mediated immune responses and responsible for the manifestation of Atopic disorders. The current study was aimed to elucidate the genetic variations of Interleukin 4 (IL4) and Interleukin 4 receptor alpha (IL4R) genes and their possible association with atopic subjects.

METHODS

The well-designed questionnaire was used to collect the subject demographic and clinical details. Biochemical parameters were analysed using Chemiluminescent Immunoassay (CLIA) technique. The genotyping was performed using Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP).

RESULTS

We observed a statistically significant difference of serum Immunoglobulin-E (IgE) levels among cases and controls (P<0.05). Subjects harbouring the variant genotypes of I50V and Q576R single nucleotide polymorphisms (SNPs) in IL4R gene showed statistically differential risk towards atopic disorders. However, the variants genotype of 70 bp VNTR polymorphism in IL4 gene showed a protective role towards in predisposition to Atopy. On stratification, the above genetic variants had a significant impact on modifiable and non-modifiable factors associated with the disease.

CONCLUSION

Our study demonstrates that increased IgE levels and IL4 gene variants (I50V and Q576R) are significantly associated towards predisposition to allergic disorders in this study population.

IL-4 rs2243250 polymorphism associated with susceptibility to allergic rhinitis: a meta-analysis

Objective: The relationship between IL-4 rs2243250 polymorphism and the risk of allergic rhinitis is not clear at present. The present study aims to evaluate the exact association between IL-4 rs2243250 polymorphism and susceptibility to allergic rhinitis by a meta-analysis.

Methods: The studies about IL-4 rs2243250 polymorphism associated with susceptibility to allergic rhinitis were searched using PubMed, Excerpta Medica Database (EMBASE), Web of Science, Cochrane Library, China National Knowledge Infrastructure (CNKI) and China Wanfang databases. The last search time was on March 1, 2021. Data analysis was performed using Stata 15.0 software.

Results: Nine documents were enrolled, from which 1709 patients with allergic rhinitis were included. Among them, six genotype frequencies in the control group conformed to Hardy–Weinberg Equilibrium (HWE). The meta-analysis of all included studies showed significant heterogeneity of each gene model. After omitting the studies whose genotype frequency in the control group did not meet the requirements of HWE, no significant heterogeneity was found in each gene model. The meta-analysis results of the control group genotypes in line with the HWE showed statistically significant differences in the pooled odds ratio (OR) of allele model (T vs. C), recessive model (TT vs. TC+CC) and homozygous model (TT vs. CC), which were 1.19 (95%CI: 1.04–1.35), 1.28 (95%CI: 1.06–1.55) and 1.56 (95%CI: 1.13–2.17), respectively. No statistically significant difference was observed in dominant and heterozygous genetic models.

Conclusion: IL-4 rs2243250 single nucleotide polymorphism associated with susceptibility to allergic rhinitis, allele T and genotype TT could increase the risk of allergic rhinitis.

Association of IL-4 Polymorphisms with Allergic Rhinitis in Jordanian Population

Background and objectives: Allergic rhinitis has complex patterns of inheritance, and single nucleotide polymorphisms, a common genetic variation in a population, exert a significant role in allergic rhinitis pathology. The current study aimed to investigate the association of Interleukin-4 (IL-4) polymorphisms with allergic rhinitis. Materials and Methods: Our study included 158 patients with allergic rhinitis and 140 healthy controls from Jordan that were genotyped for IL-4 single nucleotide polymorphisms (SNPs) C-589T (rs2243250) and T-2979G (rs2227284) using restriction fragment length polymorphism-polymerase chain reaction. Statistical analysis was conducted using IBM SPSS Statistics version 24 software. Results: The results showed that the allelic frequency of the minor alleles was 0.19 and 0.67 for C-589T (rs2243250) and T-2979G (rs2227284) in the allergic rhinitis patients, respectively, while it was 0.18 for C-589T (rs2243250) and 0.64 T-2979G (rs2227284) in the control group. The homozygous (TT) genotype of C-589T (rs2243250) was significantly associated with allergic rhinitis (p < 0.05), while there was no association of any of T-2979G (rs2227284) genotypes with allergic rhinitis. Conclusions: The results of this study indicate that genetic inter-population variation precipitates the differences in the percentages of many diseases among populations, including allergic rhinitis.

Relationships Between IL-13 and IL-4 Genotypes and Aeroallergens with Risk of Allergic Rhinitis in Iranian-Azeri

Background: Up to 40% of the world populations are affected by allergic rhinitis (AR). Interplay between genetics, epigenetics, and environmental factors leads to allergic disease. Objective: In this study, we evaluated the accompaniment between polymorphic variants of IL-13 and IL-4 and aeroallergens among Iranian-Azeri children and adolescent in AR's risk. Methods: Five-hundred AR patients and 300 healthy individuals were enrolled in this study after diagnosis via blood testing for IgE and skin prick test by subspecialty of Allergy and Immunology from Azerbaijan, northwest of Iran, from 2017 to 2019. Genomic DNA was prepared from all samples for genotyping of IL-4 and IL-13. Results: We identified genetic variation of IL-13 and IL-4 and important aeroallergens that could increase the AR risk during childhood and adolescent. The risk of AR increased in the subjects with +2044GA genotype of IL13 [adjusted odds ratio (OR), 1.80; 95% confidence interval (CI), 0.97-3.33] and -590CT genotype of IL4 (adjusted OR, 1.94; 95% CI, 1.00-3.87) in childhoods, compared with the control subjects. However, none of genotypes and allele frequencies of IL4 -590C/T and IL13 +2044G/A polymorphisms revealed significant variation between the AR patients and controls in adulthood. The frequency of sensitization to pollens was high in all genotypes of IL4 -590C/T and IL13 +2044G/A polymorphisms in both age groups of AR patients. Conclusion: AR is considered to be the most common form of atopic disease. Susceptible individuals had family history of allergic disease and indicated sensitivity to various environmental factors. In this study, pollen and feather played an important role in occurrence of AR. Childhood with GA at IL13 +2044 and CT at IL4 -590 are at increased risk for AR. Moreover, further studies with more samples are required to confirm our findings and also to help us develop new procedure for genetically detecting more efficient proceedings of prevention and intervention.

The genetic etiology of eosinophilic esophagitis

Eosinophilic esophagitis (EoE) is a chronic allergic disease associated with marked mucosal eosinophil accumulation. Multiple studies have reported a strong familial component to EoE, with the presence of EoE increasing the risk for other family members with EoE. Epidemiologic studies support an important role for environmental risk factors as modulators of genetic risk. In a small percentage of cases, including patients who have Mendelian diseases with co-occurrent EoE, rare genetic variation with large effect sizes could mediate EoE and explain multigenerational incidence in families. Common genetic risk variants mediate genetic risk for the majority of patients with EoE. Across the 31 reported independent EoE risk loci (P < 10-5), most of the EoE risk variants are located in between genes (36.7%) or within the introns of genes (42.4%). Although some variants do change the amino acid sequence of genes (2.2%), only 3 of the 31 EoE risk loci harbor an amino acid-changing variant. Thus most EoE risk loci are outside of the coding regions of genes, suggesting a key role for gene regulation in patients with EoE, which is consistent with most other complex diseases.

The Role of Interleukin-4 and 13 Gene Polymorphisms in Allergic Rhinitis: A Case Control Study

BACKGROUND

Allergic Rhinitis (AR) is an IgE-mediated inflammatory disorder with high morbidity rates. The eitiology of this disease is understood to occur from a complex interaction between genetic and environmental factors. T helper type 2 cells have been shown to have a crucial role in atopic disease due to their production of the cytokines, intelukin (IL)-13 and IL-4, involved in inflammation. Research has shown single nucleotide polymorphisms (SNP) of the IL-13 and IL-4 genes to be associated increased levels of IgE and with allergic diseases such as, allergic rhinitis, asthma, and atopic dermatitis. Specifically, the rs2243250 SNP of IL-4 and the rs20541 SNP of IL-13 have been shown to be associated with AR.

METHODS

A case-control study was designed to investigate the relationship between the two SNPs rs2243250 and rs20541 with the incidence of AR. The SNPs were examined in patients with AR and healthy controls (86 patients and 86 controls). Blood samples were collected and DNA was extracted to evaluate the SNPs by RFLP-PCR.

RESULTS

Recessive analysis model of the IL-13 gene (GG vs. AA+AG) revealed that the GG genotype was more common in AR patients (P=0.36) )OR=0.8 [81% CI 0.38-1.6]). For the IL-4 gene (TC vs. TT+CC), the TC genotype was more common in AR patients (P = 0.0022)) OR=0.71 [60% CI 1.41-5.02]). Furthermore, in the IL-4 gene, the 590 T>C polymorphism had a significant association with AR. However, no association was found between AR and the IL-13 rs20541 polymorphism.

CONCLUSION

Our findings suggest that the IL-13 polymorphism (rs20541, Exo 4, G>A, Arg130Gln) and IL-4 polymorphism (rs2243250= C-590T, promoter, T>C) are co-associated with AR and sensitivity to aeroallergens. However, this study used a cohort of AR patients and healthy controls from the northeast of Iran. Given the influence of ethnicity and environment on genetics, further investigation is needed to elucidate the role of SNPs in IL-4 and IL-13 in AR among different populations.

Identification of Novel Biomarkers for Drug Hypersensitivity After Sequencing of the Promoter Area in 16 Genes of the Vitamin D Pathway and the High-Affinity IgE Receptor

The prevalence of allergic diseases and drug hypersensitivity reactions (DHRs) during recent years is increasing. Both, allergic diseases and DHRs seem to be related to an interplay between environmental factors and genetic susceptibility. In recent years, a large effort in the elucidation of the genetic mechanisms involved in these disorders has been made, mostly based on case-control studies, and typically focusing on isolated SNPs. These studies provide a limited amount of information, which now can be greatly expanded by the complete coverage that Next Generation Sequencing techniques offer. In this study, we analyzed the promoters of sixteen genes related to the Vitamin D pathway and the high-affinity IgE receptor, including FCER1A, MS4A2, FCER1G, VDR, GC, CYP2R1, CYP27A1, CYP27B1, CYP24A1, RXRA, RXRB, RXRG, IL4, IL4R, IL13, and IL13RA1. The study group was composed of patients with allergic rhinitis plus asthma (AR+A), patients with hypersensitivity to beta-lactams (BLs), to NSAIDs including selective hypersensitivity (SH) and cross-reactivity (CR), and healthy controls without antecedents of atopy or adverse drug reactions. We identified 148 gene variations, 43 of which were novel. Multinomial analyses revealed that three SNPs corresponding to the genes FCER1G (rs36233990 and rs2070901), and GC (rs3733359), displayed significant associations and, therefore, were selected for a combined dataset study in a cohort of 2,476 individuals. The strongest association was found with the promoter FCER1G rs36233990 SNP that alters a transcription factor binding site. This SNP was over-represented among AR+A patients and among patients with IgE-mediated diseases, as compared with control individuals or with the rest of patients in this study. Classification models based on the above-mentioned SNPs were able to predict correct clinical group allocations in patients with DHRs, and patients with IgE-mediated DHRs. Our findings reveal gene promoter SNPs that are significant predictors of drug hypersensitivity, thus reinforcing the hypothesis of a genetic predisposition for these diseases.

Histamine H1 receptor gene polymorphism acts as a biological indicator of the prediction of therapeutic efficacy in patients with allergic rhinitis in the Chinese Han population

H1-antihistamine has been shown to be effective in treating patients with allergic rhinitis (AR), but its mechanism is still uncertain. We investigated effects of histamine H1 receptor (HRH1) gene polymorphisms on the efficacy of oral H1-antihistamine in perennial patients with AR caused by mites in the Chinese Han population for the first time. A total of 224 Han Chinese patients with AR and 165 Han Chinese healthy volunteers were selected. Genotype and allele frequency distribution of -17C/T in HRH1 gene in patients with AR, serum levels of eosinophil cationic protein (ECP), total immunoglobulin E (IgE), and specific IgE were detected. The clinical symptoms of patients with AR were evaluated with visual analogue scale (VAS). Direct counting method was applied to calculate genotype and allele frequencies. Higher levels of serum ECP and total IgE were shown in the AR group. Moreover, patients with CT, TT, or CT+TT genotype increased the risk of AR incidence in the in the -17C/T site of HRH1, and CC genotype and CT+TT genotype were associated with gender, asthma, VAS score, total IgE level, and specific IgE level in patients with AR. In addition, oral administration of H1-antihistamines improves clinical symptoms of patients with AR. At last, patients with the CC genotype showed the increased efficacy of H1-antihistamines in patients with AR. Our study provides evidence that HRH1 gene polymorphisms may correlate with oral H1-antihistamine efficacy for the treatment of patients with AR, which can be used as a biological indicator of the prediction of therapeutic efficacy of patients with AR.

Interleukin-4 and Interleukin-4 Receptor Alpha Gene Polymorphisms in Recurrent Aphthous Stomatitis

BACKGROUND

Recurrent aphthous stomatitis (RAS) is a common oral condition with a major impact on the quality of life. The condition is thought to be due to the overexpression of T helper-1(Th1)-related cytokines. Since interleukin-4 (IL-4) and its receptor (IL-4Rα) are antagonistic to Th-1 pathways, polymorphisms in their genes may also be involved in the pathogenesis of aphthous stomatitis.

METHODS

Sixty-four patients diagnosed with minor RAS and 141 (age- and sex-matched) healthy controls were assessed for 3 single-nucleotide polymorphisms (SNPs) within the promoter region of the IL-4 gene (-1098G/T, -590C/T, and -33C/T), and 1 SNP in IL-4Rα gene (+1902 A/G).

RESULTS

No significant differences were detected between the patient and the control group regarding IL-4 allele frequencies. However, the patient group demonstrated a higher frequency of IL-4 -590 CC genotype and a lower rate of IL-4 -590 TC genotype. The TCT, GTT, GCT, and GTC haplotypes of the IL-4 gene (-1098, -590, -33) were significantly more frequent in the patients and the GCC, and TTT haplotypes were more common in healthy controls. No significant differences were found in IL-4Rα gene polymorphism between the 2 groups.

CONCLUSIONS

Certain polymorphisms of IL4 gene could predispose individuals to RAS.

Chinese Society of Allergy Guidelines for Diagnosis and Treatment of Allergic Rhinitis

Allergic rhinitis (AR) is a global health problem that causes major illnesses and disabilities worldwide. Epidemiologic studies have demonstrated that the prevalence of AR has increased progressively over the last few decades in more developed countries and currently affects up to 40% of the population worldwide. Likewise, a rising trend of AR has also been observed over the last 2-3 decades in developing countries including China, with the prevalence of AR varying widely in these countries. A survey of self-reported AR over a 6-year period in the general Chinese adult population reported that the standardized prevalence of adult AR increased from 11.1% in 2005 to 17.6% in 2011. An increasing number of Journal Articles and imporclinical trials on the epidemiology, pathophysiologic mechanisms, diagnosis, management and comorbidities of AR in Chinese subjects have been published in international peer-reviewed journals over the past 2 decades, and substantially added to our understanding of this disease as a global problem. Although guidelines for the diagnosis and treatment of AR in Chinese subjects have also been published, they have not been translated into English and therefore not generally accessible for reference to non-Chinese speaking international medical communities. Moreover, methods for the diagnosis and treatment of AR in China have not been standardized entirely and some patients are still treated according to regional preferences. Thus, the present guidelines have been developed by the Chinese Society of Allergy to be accessible to both national and international medical communities involved in the management of AR patients. These guidelines have been prepared in line with existing international guidelines to provide evidence-based recommendations for the diagnosis and management of AR in China.

Eosinophilic esophagitis (EoE) genetic susceptibility is mediated by synergistic interactions between EoE-specific and general atopic disease loci

BACKGROUND

Eosinophilic esophagitis (EoE) is an esophageal inflammatory disease associated with atopic diseases. Thymic stromal lymphopoietin (TSLP) and calpain 14 (CAPN14) genetic variations contribute to EoE, but how this relates to atopy is unclear.

OBJECTIVE

The purpose of this study was to explore the relationship between EoE, atopy, and genetic risk.

METHODS

EoE-atopy enrichment was tested by using 700 patients with EoE and 801 community control subjects. Probing 372 single nucleotide polymorphisms (SNPs) in 63 atopy genes, we evaluated EoE associations using 412 nonatopic and 868 atopic disease control subjects. Interaction and stratified analyses of EoE-specific and atopy-related SNPs were performed.

RESULTS

Atopic disease was enriched in patients with EoE (P < .0001). Comparing patients with EoE and nonatopic control subjects, EoE associated strongly with IL-4/kinesin family member 3A (IL4/KIF3A) (P = 2.8 × 10^-6; odds ratio [OR], 1.87), moderately with TSLP (P = 1.5 × 10^-4; OR, 1.43), and nominally with CAPN14 (P = .029; OR, 1.35). Comparing patients with EoE with atopic disease control subjects, EoE associated strongly with ST2 (P = 3.5 × 10^-6; OR, 1.77) and nominally with IL4/KIF3A (P = .019; OR, 1.25); TSLP's association persisted (P = 4.7 × 10^-5; OR, 1.37), and CAPN14's association strengthened (P = .0001; OR, 1.71). Notably, there was gene-gene interaction between TSLP and IL4 SNPs (P = .0074). Children with risk alleles for both genes were at higher risk for EoE (P = 2.0 × 10^-10; OR, 3.67).

CONCLUSIONS

EoE genetic susceptibility is mediated by EoE-specific and general atopic disease loci, which can have synergistic effects. These results might aid in identifying potential therapeutics and predicting EoE susceptibility.

International consensus (ICON) on: clinical consequences of mite hypersensitivity, a global problem

Since mite allergens are the most relevant inducers of allergic diseases worldwide, resulting in significant morbidity and increased burden on health services, the International Collaboration in Asthma, Allergy and Immunology (iCAALL), formed by the American Academy of Allergy, Asthma and Immunology (AAAAI), the American College of Allergy, Asthma and Immunology (ACAAI), the European Academy of Allergy and Clinical Immunology (EAACI), and the World Allergy Organization (WAO), has proposed to issue an International Consensus (ICON) on the clinical consequences of mite hypersensitivity. The objectives of this document are to highlight aspects of mite biology that are clinically relevant, to update the current knowledge on mite allergens, routes of sensitization, the genetics of IgE responses to mites, the epidemiologic aspects of mite hypersensitivity, the clinical pictures induced by mites, the diagnosis, specific immunotherapeutic approaches, and prevention.

Interleukin-4 -590 T>C and interleukin-4 receptor Q551R A>G gene polymorphisms in Saudi cases with alopecia areata

OBJECTIVES

Immunogenetic factors are known to play a role in the pathogenesis of alopecia areata (AA). This study aimed at investigating the association between AA with the polymorphisms of interleukin-4 (IL-4) promoter and receptor (IL-4R) genes.

PATIENTS AND METHODS

This work is a case-control study that was conducted on 76 AA patients from Qassim region, Saudi Arabia. Patients were compared with 93 normal healthy controls from the same locality. Genomic DNA was extracted and processed using real-time PCR amplification for characterization of IL-4 -590 T>C and IL-4R Q551R A>G gene polymorphisms.

RESULTS

Cases of AA showed a higher frequency of the IL-4 -590 CC homozygous genotype compared with controls (63.2 vs. 53.8%, P>0.05) with a lower frequency of the TT genotype (5.3 vs. 10.8%); yet, both were statistically nonsignificant (P>0.05). Regarding the IL-4R Q551R A>G polymorphism, cases and controls showed nearly equal frequencies of all variants, that is, with no significant difference. Although the frequency of the IL-4 C and the IL-4R A alleles was higher among cases than among controls (78.9 vs. 71.5% and 78.8 vs. 72.6%, respectively), this was also statistically nonsignificant (P>0.05). Comparing case subgroups in terms of their age of onset, sex, disease severity, consanguinity, and family history showed no statistically significant difference regarding the studied genetic variant.

CONCLUSION

IL-4 -590 and IL-4R Q551R gene polymorphisms are not associated with the susceptibility and the clinical pattern of AA in Saudi patients. We recommend further research studies involving the estimation of cytokines both in the serum and in the local skin lesions or in cultured skin cells to figure out whether Th1 or Th2 pathways play a specific role in the pathogenesis of AA.

Gene Polymorphism of Interleukin-4, Interleukin-4 Receptor and STAT6 in Children with Atopic Dermatitis in Taif, Saudi Arabia

AIM OF STUDY

This work was performed to evaluate the level of IL-4, and to clarify the role of IL-4 gene polymorphism at position cytosine -590-to-thyamine (C-590T), IL-4Rα gene polymorphism at position adenine +4679-to-guanine (A+4679G) [isoleucine-50-valine (I50V)] and STAT6 gene polymorphism at position guanine 2964-to-adenine (G2964A) in Saudi children with non-atopic dermatitis (non-AD) and atopic dermatitis (AD) to identify their role in the pathogenesis of these diseases.

SUBJECTS AND METHODS

This study included 150 children: 50 healthy children as controls, 50 with non-AD, and 50 with AD. They were subjected to full clinical examination, complete blood picture, skin prick test, and determination of serum interleukin-4 (IL-4) and total immunoglobulin-E (IgE) levels. Detection of interleukin-4 gene (C-590T), interleukin-4 receptor alpha gene (A+4679G) (I50V), and STAT6 gene (G2964A) polymorphisms were performed by PCR-based restriction fragment length polymorphism (PCR-RFLP).

RESULTS

There was a significant (P < 0.01) association between genotype and allele frequencies of IL-4Rα (A+4679G) (I50V) polymorphism in the AD group (but not non-AD group). Moreover, there was a significant association between genotype and allele frequencies of the STAT6 (G2946A) polymorphism in the non-AD (P < 0.05) and AD (P < 0.01) groups. On the other hand, there was no significant association between genotype and allele frequencies of the (C-590T) polymorphism in the non-AD group and AD group. There was a significant (P < 0.001) higher total IgE level in patients compared to the controls. Moreover, the mean values of total IgE were significantly different among the different allelic variants of (C-590T), (I50V), (G2964A) polymorphisms of IL-4, IL-4Rα, and STAT6 genes, respectively, in all the studied groups. On the other hand, there was no significant difference of serum IL-4 levels among all the studied patients, or among the different allelic variants of (C-590T), (I50V), (G2964A) polymorphisms of IL-4, IL-4Rα, and STAT6 genes, respectively.

CONCLUSION

IL-4Rα gene (I50V) and STAT6 gene (G2964) polymorphisms may play a role in development of eczema; however, the IL-4 gene polymorphism (C-590T) had no relationship with susceptibility to the disease among Saudi children.

Association of VDR and CYP2R1 Polymorphisms with Mite-Sensitized Persistent Allergic Rhinitis in a Chinese Population

As recent studies have described an association between vitamin D and allergic rhinitis, we hypothesized that vitamin D pathway-related genes may be candidate genes for susceptibility to allergic rhinitis. Thus, we sought to evaluate whether polymorphisms in the vitamin D receptor (VDR) and CYP2R1 genes are associated with mite-sensitized persistent allergic rhinitis (PER) in a Han Chinese population. A hospital-based case-control study consisting of 519 patients with mite-sensitized PER and 447 healthy controls was conducted. Five single nucleotide polymorphisms (SNPs) in VDR and CYP2R1 were selected for genotyping. The genotype and allele frequencies of rs9729, rs2228570, rs1544410, and rs731236 in VDR as well as rs2060793 in CYP2R1 were not significantly associated with susceptibility to mite-sensitized PER. After stratification analyses, however, both the CT and CT/TT genotypes of rs2228570 in VDR exhibited a significantly decreased risk (CT: adjusted odds ratio (OR)=0.58, 95% confidence intervals (CI)=0.37-0.91; CT/TT: adjusted OR=0.61, 95% CI=0.40-0.93) of mite-sensitized PER, while the AA genotype of rs2060793 in CYP2R1 exhibited a significantly increased risk (adjusted OR=1.85, 95% CI=1.03-3.34) of PER in the age subgroup of <16 years old. Both the AG and AG/GG genotypes of rs731236 in VDR exhibited a significantly decreased risk (AG: adjusted OR=0.43, 95% CI=0.21-0.89; AG/GG: adjusted OR=0.46, 95% CI=0.23-0.94) of PER in the female subgroup. Analysis of the locus-locus interactions of VDR and CYP2R1 revealed two models that involved combined SNPs of VDR and CYP2R1 were statistically significant (P<0.05). Our data suggest that age and gender may have an impact on the association of three SNPs (rs2228570, rs731236, and rs2060793) in genes of the vitamin D pathway with the risk of mite-sensitized PER in this Chinese population. The VDR and CYP2R1 variants may be involved in genetic interactions in the pathogenesis of PER.

Discovering susceptibility genes for allergic rhinitis and allergy using a genome-wide association study strategy

PURPOSE OF REVIEW

Allergic rhinitis and allergy are complex conditions, in which both genetic and environmental factors contribute to the pathogenesis. Genome-wide association studies (GWASs) employing common single-nucleotide polymorphisms have accelerated the search for novel and interesting genes, and also confirmed the role of some previously described genes which may be involved in the cause of allergic rhinitis and allergy. The aim of this review is to provide an overview of the genetic basis of allergic rhinitis and the associated allergic phenotypes, with particular focus on GWASs.

RECENT FINDINGS

The last decade has been marked by the publication of more than 20 GWASs of allergic rhinitis and the associated allergic phenotypes. Allergic diseases and traits have been shown to share a large number of genetic susceptibility loci, of which IL33/IL1RL1, IL-13-RAD50 and C11orf30/LRRC32 appear to be important for more than two allergic phenotypes. GWASs have further reflected the genetic heterogeneity underlying allergic phenotypes.

SUMMARY

Large-scale genome-wide association strategies are underway to discover new susceptibility variants for allergic rhinitis and allergic phenotypes. Characterization of the underlying genetics provides us with an insight into the potential targets for future studies and the corresponding interventions.

Association of cytokines in individuals sensitive and insensitive to dust mites in a Brazilian population

Introduction

Allergic reaction to dust mites is a relatively common condition among children, triggering cutaneous and respiratory responses that have a great impact on the health of this population. Anaphylactic hypersensitivity is characterized by an exacerbated response involving the production of regulatory cytokines responsible for stimulating the production of IgE antibodies.

Objective

To investigate an association of variants in cytokine genes (IL1A⁻⁸⁸⁹, IL1B^{−511, +3962}, IL1R¹⁹⁷⁰, IL1RA¹¹¹⁰⁰, IL4RA⁺¹⁹⁰², IL12⁻¹¹⁸⁸, IFNG⁺⁸⁷⁴, TGFB1^{codon 10, codon 25}, TNFA^{−308, −238}, IL2^{−330, +166}, IL4^{−1098, −590, −33}, IL6^{−174, nt565}, and IL10^{−1082, −819, −592}) between patients sensitive to dust mites and a control group.

Methods

A total of 254 patients were grouped as atopic and non-atopic according to sensitivity as evaluated by the Prick Test and to cytokine genotyping by the polymerase chain reaction-sequence specific primers (PCR-SSP) method using the Cytokine Genotyping Kit.

Results

A comparison between individuals allergic to Dermatophagoides farinae, Dermatophagoides pteronyssinus, and Blomia tropicalis and a non-atopic control group showed significant differences between allele and genotype frequencies in the regulatory regions of cytokine genes, with important evidence for IL4⁻⁵⁹⁰ in T/C (10.2% vs. 43.1%, odd ratio [OR] = 0.15, p = 5.2 10⁻⁸, pc = 0.0000011, and 95% confidence interval [95%CI] = 0.07–0.32) and T/T genotypes (42.9% vs. 13.8%, OR = 4.69, p = 2.5 10⁻⁶, pc = 0.000055, and 95%CI = 2.42–9.09). Other associations were observed in the pro-inflammatory cytokines IL1A⁻⁸⁸⁹ (T/T, C, and T) and IL2⁻³³⁰ (G/T and T/T) and the anti-inflammatory cytokines IL4RA⁺¹⁹⁰² (A and G), IL4⁻⁵⁹⁰ (T/C, T/T, C, and T), and IL10⁻⁵⁹² (A/A, C/A, A, and C).

Conclusion

Our results suggest a possible association between single nucleotide polymorphisms (SNPs) in cytokine genes and hypersensitivity to dust mites.

Association between promoter polymorphisms of interleukin-4 gene and allergic rhinitis risk: a meta-analysis

The relationship of interleukin-4 (IL-4) C-33T and C-590T (C-589T) gene polymorphisms with allergic rhinitis was analyzed. Data about the case control studies of IL-4 gene promoter polymorphisms [C-33T and C-590T (C-589T)] and their association with allergic diseases and correlation between serum IL-4 levels and allergic rhinitis were retrieved. The Stata 12.0 statistical software was applied to analyze the correlation between IL-4 gene polymorphisms and allergic rhinitis. The meta-analysis result of TT/CC genotype of -590 (-589) polymorphism showed a significant association with allergic diseases [OR=1.93, 95% CI (1.61-2.31), P=0.00]. Meta-analysis of the TT+TC versus CC genotype of IL-4 C-33/T polymorphism revealed significant associations with allergic diseases [OR=3.23, 95% CI (1.13-9.25), P=0.03]. Meanwhile, there was a significant correlation between serum IL-4 levels and allergic rhinitis [OR=2.52, 95% CI=(1.80-3.23), P=0.00]. IL-4 gene -590 TT genotype may increase the risk of allergic rhinitis and the T allele mutation of -33 might be correlated with allergic rhinitis.

High risk association of IL-4 VNTR polymorphism with asthma in a North Indian population

BACKGROUND

A case-control study was conducted to evaluate the role of IL-4 VNTR polymorphism in asthma that has been associated with various inflammatory diseases worldwide. This is the first case-control study conducted in India, investigating the role of IL-4 VNTR polymorphism in asthma pathogenesis.

METHODS

A case-control study was performed with a total of 824 adult subjects, inducting 410 asthma patients and 414 healthy controls from North India. The genotypes were identified by polymerase chain reaction.

RESULTS

Statistical analysis for the IL-4 VNTR polymorphism revealed that the Rp1 allele was significantly associated with asthma with OR=1.47, 95% CI (1.11-1.94) and p=0.005. The Rp1/Rp1 homozygous mutant genotype posed a high risk towards asthma with OR=2.39, 95% CI (0.96-6.14) and p=0.040. The Rp2/Rp1 heterozygous genotype also posed a risk towards asthma with OR=1.39, 95% CI (1.00-1.94) and p=0.040. Most of the phenotypic traits were significantly associated with the disease.

CONCLUSIONS

IL-4 VNTR polymorphism is a high risk factor for asthma in the studied North Indian population.

Comparison of the nasal release of IL-4, IL-10, IL-17, CCL13/MCP-4, and CCL26/eotaxin-3 in allergic rhinitis during season and after allergen challenge

BACKGROUND

Allergic rhinitis is an inflammatory disease characterized by local overproduction of type 2 cytokines and tissue eosinophilia. Recent research suggests the involvement of additional cytokines such as IL-17, chemokine (C-C motif) ligand (CCL) 26/eotaxin-3, and CCL13/monocyte chemoattractant protein-4 (MCP-4) in its pathophysiology. Furthermore, bronchial epithelial cells treated with IL-17 and type 2 cytokines distinctively up-regulated eotaxin-3 gene expression. In this study we investigated the kinetics of IL-4, IL-10, IL-17, eotaxin-3, and MCP-4 in seasonal allergic rhinitis volunteers after nasal allergen challenge (NAC) and their release during natural pollen exposure.

METHODS

The nasal lavages of 15 symptomatic allergic and 14 nonallergic subjects were collected during the pollination season. Additionally, six allergic subjects underwent a single unilateral nasal allergen and control challenge out of season, and nasal secretions were collected. Levels of IL-4, IL-10, IL-17, eotaxin-3, and MCP-4 in nasal lavages and secretions were measured using an electrochemiluminescent assay.

RESULTS

After NAC, allergic subjects had a significant immediate response of nasal symptoms as well as a significant increase at 5 hours of IL-4, IL-10, and IL-17 and at 2, 5, and 24 hours significantly raising levels of eotaxin-3. IL-17 and eotaxin-3 concentrations at 5 hours were correlated (r = 0.94; p = 0.005). During natural pollen exposure, barely detectable levels of IL-17 in allergic subjects were also correlated with eotaxin-3 (r = 0.62; p = 0.01). Eotaxin-3 and MCP-4 levels were significantly elevated 9- or 3.7-fold, respectively, and IL-10 and, unexpectedly, IL-4 were significantly lower in allergic subjects compared with nonallergic subjects.

CONCLUSION

Nasal IL-17, MCP-4, and, possibly, eotaxin-3 may aggravate and IL-10 may alleviate nasal mucosal allergy.

Interleukin-4 receptor α-chain polymorphisms and susceptibility to allergic rhinitis: a meta-analysis

Several polymorphisms in interleukin-4 receptor α-chain (IL-4RA) have been implicated in susceptibility to allergic rhinitis (AR), but the results are inconclusive. This meta-analysis was aimed to clarify the impact of IL-4RA polymorphisms on AR risk. Pubmed, EMBASE and Cochrane Library were searched until 2 October 2013 for eligible studies on IL-4RA polymorphism. Data were extracted, and pooled odd ratios (ORs) as well as 95 % confidence intervals (95 % CIs) were calculated. Ten studies with 1,552 AR patients and 1,473 controls were included. The results indicated that IL4RA Gln551Arg polymorphism was associated with AR susceptibility in Asian (AG vs. AA OR = 1.63, 95 % CI 1.17-2.28, I (2) = 57 %; GG vs. AA, OR = 1.69, 95 % CI 1.00-2.86, I (2) = 7 %; AG + GG vs. AA, OR = 1.68, 95 % CI 1.18-2.39, I (2) = 64 %; GG vs. AG + AA, OR = 1.47, 95 % CI 0.87-2.49, I (2) = 0 %; G vs. A, OR = 1.54, 95 % CI 1.14-2.10, I (2) = 64 %) but not in Caucasian. IL4RA Ile50 Val as well as Ser478Pro polymorphisms were not associated with AR susceptibility both in Asian and in Caucasian. Gene-gene and gene-environment interactions should be investigated in the future.

Gene polymorphisms of Interleukin-4 in allergic rhinitis and its association with clinical phenotypes

BACKGROUND

Allergic rhinitis (AR) is an inflammatory disorder of the upper airway. T-helper (Th)2 cytokines seems to have major roles behind the scene of unpleasant symptoms resulted from AR. Expression of interleukin (IL)-4 and its receptor could be affected by single nucleotide polymorphisms (SNPs). This study assessed the effect of 4 genetic variants within genes of IL-4 and IL-4R in AR.

METHODS

Allele frequencies of one IL-4R variant (rs1801275) and three SNPs of IL-4 (rs2243248, rs2243250, and rs2070874) were investigated in 98 patients with AR, compared to a group of controls, using PCR sequence-specific-primers (PCR-SSP) method.

RESULTS

Homozygosity for the C allele of rs2243250 in IL-4 was significantly overrepresented in the patient group. CC genotype in rs2070874 significantly was correlated with AR. GG/CC/CC and TT/TT/TT (rs2243248, rs2243250, and rs2070874) haplotypes in the IL-4 gene had a significant negative correlation with AR.

CONCLUSION

SNPs in IL-4 are associated with AR and could change the clinical picture of the disease in patients.

Association of interleukin-13 SNP rs20541 with allergic rhinitis risk: a meta-analysis

Studies investigating the association between interleukin-13 (IL-13) single nucleotide polymorphism (SNP) rs20541 and allergic rhinitis (AR) risk have reported conflicting results. The aim of the present study was to conduct a meta-analysis assessing the possible association of IL-13 SNP rs20541 with AR risk. Eight studies were included in the present meta-analysis (2153 cases and 3931 controls). The combined results based on all studies showed that IL-13 SNP rs20541 was associated with increased AR risk (Gln versus Arg: odds ratio (OR)=1.18, 95% confidence interval (CI)=1.08-1.30; Gln/Gln versus Arg/Arg: OR=1.52, 95% CI=1.20-1.92; Arg/Gln+Gln/Gln versus Arg/Arg: OR=1.19, 95% CI=1.06-1.33; Gln/Gln versus Arg/Gln+Arg/Arg: OR=1.42, 95% CI=1.13-1.79). When stratifying for race, IL-13 SNP rs20541 exhibited increased AR risk in Asians (Gln versus Arg: OR=1.20, 95% CI=1.06-1.36; Gln/Gln versus Arg/Arg: OR=1.57, 95% CI=1.17-2.12; Arg/Gln+Gln/Gln versus Arg/Arg: OR=1.22, 95% CI=1.04-1.44; Gln/Gln versus Arg/Gln+Arg/Arg: OR=1.45, 95% CI=1.09-1.93), while no significant association was detected in Caucasians (Gln versus Arg: OR=1.28, 95% CI=0.93~1.78; Gln/Gln versus Arg/Arg: OR=1.42, 95% CI=0.96-2.11; Arg/Gln+Gln/Gln versus Arg/Arg: OR=1.35, 95% CI=0.89-2.05; Gln/Gln versus Arg/Gln+Arg/Arg: OR=1.37, 95% CI=0.93-2.02). This meta-analysis supported that IL-13 SNP rs20541 was associated with AR, particularly in Asians.

Cytokine gene polymorphisms in Tunisian endemic pemphigus foliaceus: a possible role of il-4 variants

Polymorphism in the genes of TH2 cytokines and/or theirs receptors can influence serum cytokine levels in and the switch to the pathologic IgG4 auto-antibodies. In order to underline the role of these genes in the aethiopathogenesis of Pemphigus Foliaceus, we conduct a familial and a case control studies including 80 Tunisian patients, 147 related subjects and 160 matched healthy controls. We investigated, by PCR-RFLP technique, seven nucleotide polymorphisms: rs2243250 in promoter region of IL4 gene, rs47877948, rs3024530 and rs30246223 in the IL4R gene, rs1881457and rs205412 SNPs in IL13 gene and rs535036 in IL13RA2 gene. After Bonferroni adjustment, T allele and the TT genotype of IL4-590 were significantly increased in the PF patients group compared to healthy controls. This association was confirmed by the family study. Interestingly, the serum IL-4 levels were significantly increased in patients with the TT genotype compared to CT or CC genotypes. Interestingly, the IL4/IL13:T-A-C haplotype exhibited a significant effect on PF susceptibility. In addition, a significant gene-gene interaction between the IL4/IL4R (TACA) significantly increases in PF patients as compared to controls. These findings assess the role of the IL4/IL4R axis in the aethiopathogenesis of Tunisian endemic PF by the induction of a high transcriptional activity which could enhance the T-cell balance and inducing immunoglobulin isotype switching.

Polymorphisms in the IL4 gene, smoking, and rhinoconjunctivitis in Japanese women: the Kyushu Okinawa Maternal and Child Health Study

Epidemiological evidence on the relationship between IL4 single nucleotide polymorphisms (SNPs) and allergic rhinitis is limited. We conducted a case-control study to investigate this issue in young adult Japanese women. Included were 393 women who met the criteria of the International Study of Asthma and Allergies in Childhood (ISAAC) for rhinoconjunctivitis. Controls were 703 women without rhinoconjunctivitis based on the ISAAC criteria who had not been diagnosed with allergic rhinitis and/or asthma by a doctor. Compared with the TT genotype of IL4 SNP rs2227284, the GG genotype, occurring in 10.2% of control subjects, was significantly inversely associated with the risk of rhinoconjunctivitis: the adjusted OR was 0.60 (95% CI: 0.37-0.98). There were no significant relationships between SNP rs2243250, rs2070874, or rs2243290 and rhinoconjunctivitis. None of the haplotypes were significantly related to rhinoconjunctivitis. A significant inverse relationship between the combination of the TG and GG genotypes of SNP rs2227284 and rhinoconjunctivitis was observed in women who had never smoked, but not in those who had ever smoked (P for interaction=0.11). This is the first study to demonstrate a significant relationship between IL4 SNP rs2227284 and rhinoconjunctivitis. Smoking may modify the relationship between SNP rs2227284 and rhinoconjunctivitis.

Association of interleukin-13 SNP rs1800925 with allergic rhinitis risk: a meta-analysis based on 1,411 cases and 3169 controls

Studies investigating the association between interleukin-13 (IL-13) single nucleotide polymorphism (SNP) rs1800925 and allergic rhinitis risk have reported conflicting results. The aim of the present study was to conduct a meta-analysis assessing the possible association of IL-13 SNP rs1800925 with allergic rhinitis risk. The relevant studies were identified through a search of PubMed, Embase, ISI Web of Knowledge and Chinese National Knowledge Infrastructure until December 2011 and selected on the basis of the established inclusion criteria for publications. Five studies were included in the present meta-analysis (1411 cases and 3169 controls). The combined results based on all studies showed that IL-13 SNP rs1800925 was not associated with increased allergic rhinitis risk (T versus C: odds ratio (OR)=1.06, 95% confidence interval (CI)=0.94-1.20; C/T versus C/C: OR=1.12, 95% CI=0.97-1.29; T/T versus C/C: OR=1.00, 95% CI=0.69-1.44; C/T+T/T versus CC: OR=1.10, 95% CI=0.96-1.27; T/T versus C/C+C/T: OR=0.91, 95% CI=0.64-1.31). This meta-analysis supported that IL-13 SNP rs1800925 was not associated with allergic rhinitis.