Association pattern of interleukin-1 receptor-associated kinase-4 gene polymorphisms with allergic rhinitis in a Han Chinese population

Potential associations between variants of genes encoding regulators of inflammation, and mediators of inflammation in type 2 diabetes and insulin resistance

WHAT IS KNOWN AND OBJECTIVE

Type 2 diabetes (T2DM) is a multigenic disease that develops with impaired β-cell function and insulin sensitivity and has a high prevalence worldwide. A cause often postulated for type 2 diabetes is chronic inflammation. It has been suggested that inflammatory regulators can inhibit insulin signal transduction and that inflammation is involved in insulin resistance (IR) and the pathogenesis of type 2 diabetes. In this direction, we aimed to investigate the gene variants of MyD88 (rs1319438, rs199396), IRAK4 (rs1461567, rs4251513, rs4251559) and TRAF6 (rs331455, rs331457) and serum levels of COX-2, NF-κB, iNOS in T2DM and IR.

METHODS

The MyD88, IRAK4 and TRAF6 variations were genotyped in 100 newly diagnosed T2DM patients and 100 non-diabetic individuals using The MassARRAY® Iplex GOLD SNP genotyping method. The COX-2, iNOS and NF-κB levels were measured in serum samples with the sandwich-ELISA method. Results were analysed using SPSS Statistics software and the online FINNETI program.

RESULTS AND DISCUSSION

In our study, a total of the 7 variants in the MyD88, IRAK4 and TRAF6 genes were genotyped, and as a result, no relationship was found between most of these variants and the risk of type 2 diabetes and insulin resistance (p > 0.05). Only, the rs1461567 variant of the IRAK4 gene was significant in the heterozygous model (CC vs. CT), and the CT genotype was most frequent in diabetic individuals compared with the non-diabetics (p = 0.033). Additionally, COX-2 and iNOS levels were found to be associated with diabetes and insulin resistance (p < 0.05).

WHAT IS NEW AND CONCLUSION

Our results show that high COX-2 and iNOS levels are associated with T2DM, besides MyD88, IRAK4 and TRAF6 gene variations may not be closely related to type 2 diabetes and insulin resistance. Nevertheless, studies in this pathway with a different population and a large number of patients are important.

Single-nucleotide polymorphisms and haplotypes in the interleukin-33 gene are associated with a risk of allergic rhinitis in the Chinese population

Allergic rhinitis (AR) is a common upper airway disease attributed to a variety of risk factors, such as environmental exposures and genetic susceptibility. The commonly observed comorbidity of asthma and AR in the clinic suggests the presence of shared genetic risk factors and biological mechanisms between these diseases. Interleukin (IL)-33 has been indicated to be an important factor driving asthma susceptibility and pathogenesis using both genome-wide association studies and functional studies in model animals. Although previous studies have reported the putative association of this gene with AR, evidence for the association of genetic variations of IL-33 with the disease is still missing. To examine whether variations in the IL-33 gene confer a genetic risk of AR, a total of 769 patients with AR and 769 age- and sex-matched healthy controls were recruited among Han Chinese residents in the Hubei province, and 14 single-nucleotide polymorphisms (SNPs) spanning the IL-33 gene were examined for their association with the risk of AR. The results indicated that five SNPs, which were in a moderate linkage disequilibrium and were located in the 5'-flanking region of IL-33, exhibited significant associations with the risk of AR, and these associations were additionally supported by genotypic and haplotypic analyses. Notably, three of the five IL-33 SNPs have been previously reported to exhibit genome-wide associations with asthma, and their alleles were also revealed to confer an increased risk of AR in the present study. In summary, the results of the current study suggested that certain variations in the IL-33 gene represent a potential risk for AR, and indicated a shared genetic basis between AR and asthma.

Irak-4 rs4251481 gene variant: as a risk factor on inflammatory bowel disease

Background/aim

Abnormal immune response occurs in individuals who have alleles associated with innate and adaptive immune mechanisms that predispose to inflammatory bowel disease (IBD). Interleukin-1 receptor-associated kinase 4 (IRAK-4) involved in the pathway produces cytokines that initiate and maintain inflammation through Toll-like receptors and interleukin-1 receptors on the membranes of innate immune cells are stimulated with antigens. It was aimed to investigate whether IRAK-4 rs3794262 and rs4251481 polymorphisms predispose to IBD and the possible effects of these polymorphisms by examining these gene polymorphisms with the clinic and prognostic parameters of IBD.

Material and methods

Real-time PCR technique was used to detect IRAK-4 polymorphisms in 107 patients with IBD and 103 healthy controls.

Results

As a result of experimental studies, the frequency of occurrence of rs4251481 polymorphism related AG genotype (P = 0.029) and G allele (P = 0.005) was found to increase statistically in patients compared to controls. In the control group, the rs4251481 AA genotype rate of incidence increased compared with the patient group (P = 0.005).

Conclusion

Consequently, this is the first study in terms of both polymorphisms on IBD. These results suggest that rs4251481 AG genotype and G allele are associated with increased IBD risk in patients.

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.

Neonatal Immune State Is Influenced by Maternal Allergic Rhinitis and Associated With Regulatory T cells

Purpose

Maternal influences contribute to the origin of allergic diseases, but the mechanisms are not clear. The current literature prompted the role of epigenetics in the development of allergic diseases. We sought to investigate the roles of regulatory T (Treg) cells and Forkhead box p3 (Foxp3) DNA methylation in the process of maternal transmission of allergic rhinitis (AR) susceptibility.

Methods

BALB/c female mice (AR mother) were sensitized by intraperitoneal injection of Dermatophagoides pteronyssinus (Der p) 1 on day 1 and 7. Then they mated with normal male mice on day 8. From day 21 to 28, the female mice were intranasal challenged with Der p 1 continuously. The normal controls were given with normal saline in the same way. On postnatal day 3, Female mice and their offspring were sacrificed to detect their histopathology in nasal mucosae, cytokines in sera of mother and spleen homogenates of offspring, Treg cells count, Foxp3 mRNA expressions, and Foxp3 DNA methylation levels in spleens.

Results

Compared with the normal controls, neonatal offspring of Der p 1-stimulated female mice (AR offspring) showed the elevation of interleukin (IL)-4 (P<0.01) and IL-17 (P<0.01), the submission of IL-10 (P<0.01) in spleen homogenates. Further, Treg cells count in AR offspring decreased remarkably compared with the normal offspring (P<0.01). Though the difference of Foxp3 DNA methylation level between AR offspring and normal control offspring was not obvious, correlation analysis demonstrated that there was significantly positive correlation between Foxp3 DNA methylation level of mother and that of offspring (r=0.803, P<0.01).

Conclusions

Under the influence of Maternal AR, their neonatal offspring develop into T-helper type 2 (Th2) dominant immune state, which is closely associated with the recession of Treg cells. Foxp3 DNA methylation may be a mechanism responsible for that maternal effect but still need more studies to ensure.

PID in Disguise: Molecular Diagnosis of IRAK-4 Deficiency in an Adult Previously Misdiagnosed With Autosomal Dominant Hyper IgE Syndrome

Autosomal recessive IL-1R-associated kinase 4 (IRAK-4) deficiency is a rare cause of recurrent pyogenic infections with limited inflammatory responses. We describe an adult female patient with severe lung disease who was phenotypically diagnosed as suffering from autosomal dominant Hyper IgE syndrome (AD HIES) because of recurrent skin infections with Staphylococcus aureus, recurrent pneumonia and elevated serum IgE levels. In contrast to findings in AD HIES patients, no abnormalities were found in the Th17 and circulating follicular helper T cell subsets. A panel-based sequencing approach led to the identification of a homozygous IRAK4 stop mutation (c.877C > T, p.Gln293*).

Association between the Interaction of Key Genes Involved in Effector T-Cell Pathways and Susceptibility to Develop allergic Rhinitis: A Population-Based Case-Control Association Study

Background

Evidence suggests that interaction between key genes mediating signaling and transcriptional networks involving effector T-cell responses may influence an individual’s susceptibility to develop allergic rhinitis(AR).

Objective

The aim of this study was todetermine whether specific interactions between key genes involved in effector T-cell pathways are associated with an individual’s susceptibility to develop AR in Han Chinese subjects.

Method

A cohort of 489 patients with AR and 421 healthy controls was enrolled from the Han Chinese population in Beijing, China. AR was established by questionnaire and clinical examination, and peripheral blood was drawn from all subjects for DNA extraction. A total of 96 single nucleotide polymorphisms (SNPs) in 26 reprehensive candidate genes involved in T helper 1 (Th1), Th2, Th17, Th9 and T regulatory cell pathways were selected from the International Haplotype Mappingdatabase for Han Chinese in Beijing (CHB) population, and IlluminaGoldenGate assay was conducted for SNP genotyping. The PLINK software package was used to perform statistical analyses.

Results

Simple SNP-phenotype association analysis using logistic regression showed SNP rs8193036 in IL17A gene, rs2569254 in IL-12 and rs1898413 in RORα weresignificantlyassociatedwith AR.Simple SNP-phenotype association analysis with genetic models demonstrated thatrs2569254 in IL-12, rs1031508 in STAT4, and rs3741809 in IL-26 were likely to be recessive, rs8193036 in IL17A allelic, rs897200in STAT4 genotypic, and rs1898413 in RORα dominant. Epistasis analyses exhibited that 83 SNPs in 23 genes were significantly interactive; of which 59 interactions/SNP pairs demonstrated OR values higher than 2 or lower than 0.5, and 12 interactions/SNP pairs OR values higher than 4 or lower than 0.25. STAT3, RORα and IL-26, involved in Th17 pathway,were the mostfrequentlyinteractive genes.

Conclusion

This study suggests that interactions between several SNPs in key genes involved in effector T-cell pathways are likely to influence an individual’s susceptibility to develop AR.

IRAK4 gene polymorphism and odontogenic maxillary sinusitis

Objectives

This study aimed to evaluate whether a specific interleukin-1 receptor-associated kinase-4 (IRAK4) gene polymorphism had any influence on the development of changes in maxillary sinus, particularly in the presence of etiological factors of dental origin.

Materials and methods

The study population included 153 Portuguese Caucasians that were selected from a database of 504 retrospectively analysed computed tomography (CT) scans. A genetic test was performed, and a model was created through logistic analysis and regression coefficients. The statistical methodologies included were the independent Chi test, Fisher’s exact test, binary logistic regression and the receiver operating characteristic (ROC) curve.

Results

The estimated prevalence of IRAK4 gene polymorphism found in a Portuguese Caucasian population was 26.8 % (CI 95 %) [20.1, 34.7 %]. A model to predict the inflammatory response in the maxillary sinus in the presence etiological factors of dental origin was constructed. This model had the following as variables: previously diagnosed sinusitis, sinus pressure symptoms, cortical bone loss observed on CT, positive genetic test result and radiographic examination that revealed the roots of the teeth communication with the maxillary sinus, which are interpreted as risk factors.

Conclusions

The constructed model should be considered an initial clinical tool. The area under the ROC curve found, AUC = 0.91, revealed that the model correctly predicts the outcome in 91.1 % of cases.

Clinical relevance

The clinical relevance of this study lies in trying to achieve a potential tool (a model) that may assist the clinician in the implementation of suitable dental treatment plans in complex cases, with probable involvement of the maxillary sinus.

Association between polymorphisms of the IL-23R gene and allergic rhinitis in a Chinese Han population

OBJECTIVE

Polymorphism of the interleukin-23 receptor gene corresponds with susceptibility to several immune-related diseases. For the terminal differentiation of IL-17-producing effector T-helper cells in vivo, the interleukin-23 receptor gene is of vital importance. As shown recently, Th17 cells probably have a great influence on the pathogenesis of allergic airway diseases. Our intention was to establish an association between polymorphisms in the IL-23R gene and allergic rhinitis (AR) in the Chinese Han population.

METHODS

We included 358 AR patients and 407 control Chinese subjects in a case-control comparison. The study involved obtaining blood samples for DNA extraction genotyping and determination of 4 selected single-nucleotide polymorphisms in IL-23R by performing PCR restriction fragment length polymorphism analysis (PCR-RFLP).

RESULTS

A substantially growing prevalence of the homozygous rs7517847 GG genotype and G allele appeared in the AR patients unlike that observed in the control individuals (P<0.001). In addition, substantially high frequencies of the GGCA and GGCG haplotypes were observed in the AR patients, unlike that observed in the control individuals (P<0.05). The results suggest that the AGTG haplotype may provide protection against AR (P<0.001).

CONCLUSIONS

To the best of our knowledge, this is the first study to demonstrate an important association between polymorphisms in IL-23R and AR in the Chinese Han population. A strong association between rs7517847 in a SNP of IL-23R, and AR was identified.

Polymorphisms in RYBP and AOAH genes are associated with chronic rhinosinusitis in a Chinese population: a replication study

Background

The development of CRS is believed to be the result of combined interactions between the genetic background of the affected subject and environmental factors.

Objectives

To replicate and extend our recent findings from genetic association studies in chronic rhinosinusitis (CRS) performed in a Canadian Caucasian population in a Chinese population.

Methods

In a case-control replication study, DNA samples were obtained from CRS with (n = 306; CRSwNP) and without (n = 332; CRSsNP) nasal polyps, and controls (n = 315) in a Chinese population. A total of forty-nine single nucleotide polymorphisms (SNPs) selected from previous identified SNPs associated with CRS in Canadian population, and SNPs from the CHB HapMap dataset were individually genotyped.

Results

We identified two SNPs respectively in RYBP (rs4532099, p = 2.15E–06, OR = 2.59) and AOAH (rs4504543, p = 0.0001152, OR = 0.58) significantly associated with whole CRS cohort. Subgroup analysis for the presence of nasal polyps (CRSwNP and CRSsNP) displayed significant association in CRSwNP cohorts regarding to one SNP in RYBP (P = 3.24^E–006, OR = 2.76). Evidence of association in the CRSsNP groups in terms of 2 SNPs (AOAH_rs4504543 and RYBP_rs4532099) was detected as well. Stratifying analysis by gender demonstrated that none of the selected SNPs were associated with CRSwNP as well as CRSsNP. Meanwhile 3 SNPs (IL1A_rs17561, P = 0.005778; IL1A_rs1800587, P = 0.009561; IRAK4_rs4251513, P = 0.03837) were associated with serum total IgE level.

Conclusions

These genes are biologically plausible, with roles in regulation of transcription (RYBP) and inflammatory response (AOAH). The present data suggests the potential common genetic basis in the development of CRS in Chinese and Caucasian population.