Hou-Yong Kang

Association between Interleukin-27 gene polymorphisms and susceptibility to allergic rhinitis

OBJECTIVES Allergic rhinitis (AR) is an inflammatory disorder of the upper airway. Interleukin-27 (IL-27), a novel IL-12 family member, has recently been reported to play a role in some immune-related disorders. This study was performed to evaluate the potential association of IL-27 polymorphisms with AR in a Chinese Han population. DESIGN AND METHODS A case-control study was performed in 445 Chinese AR patients and 691 healthy controls. Three SNPs in the IL-27p28 gene, including rs153109, rs17855750 and rs181206, were detected using a polymerase chain reaction-restriction fragment length polymorphism assay (PCR-RFLP). RESULTS A significantly increased prevalence of the rs153109 TT genotype and the T allele was found in AR patients, while a decreased prevalence of the CT and CC genotypes and the C allele was found. For rs153109, the TT genotype and the T allele were significantly associated with the risk of AR, but the CT and CC genotypes and the C allele decreased the risk of AR; for rs17855750, the TT genotype and T allele were risk factors for AR, and the GT genotype and G allele provided protection. TTT and TTC haplotypes in the IL-27p28 gene were positively correlated with AR, while CGT, CTC and CTT haplotypes were associated with a significantly decreased risk of AR. CONCLUSION This study indicates that IL-27p28 polymorphisms rs153109 and rs17855750 are likely involved in AR susceptibility, making them potentially useful genetic biomarkers for AR susceptibility in the Chinese Han population.

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.

An aryl hydrocarbon receptor ligand acts on dendritic cells and T cells to suppress the Th17 response in allergic rhinitis patients.

A predominant Th17 population is a marker of allergic rhinitis (AR). The aryl hydrocarbon receptor (AhR) exhibits strong immunomodulation potential via regulation of the differentiation of T lymphocytes and dendritic cells (DCs) after activation by its ligand, such as 2-(1′H-indole-3′-carbonyl)-thiazole-4-carboxylic acid methyl ester (ITE). The aim of this study was to analyze the effect of AhR on Th17 differentiation by investigating the action of ITE on DCs and CD4+ T cells from patients with AR. In all, 26 AR patients and 12 healthy controls were included in this study. The expression of interleukin (IL)-1β, IL-6, IL-10, and IL-17 in the culture supernatant and the presence of Th17 cells in CD4+ T cells and DC–CD4+ T-cell co-culture system were measured before and after treatment with ITE. We show that ITE significantly induced cell secretion of IL-10 and inhibited IL-1β and IL-6 production in DCs, and promoted IL-10 production and suppressed IL-17 expression in CD4+ T cells in vitro. It also suppressed the expansion of Th17 cells in vitro. Our work demonstrates that ITE acts on DCs and CD4+ T cells to inhibit the Th17 response that suppresses AR; the AhR–DC–Th17 axis may be an important pathway in the treatment of AR. ITE, a nontoxic AhR ligand, attenuated the Th17 response; thus, it appears to be a promising therapeutic candidate for suppressing the inflammatory responses associated with AR.

Role of the Aryl Hydrocarbon Receptor in the Pathogenesis of Chronic Rhinosinusitis with Nasal Polyps

A predominant Th17 population is a marker of chronic rhinosinusitis with nasal polyps (CRSwNP) in Chinese patients. As a ligand-activated transcription factor, the aryl hydrocarbon receptor (AhR) plays a vital role in promoting or inhibiting specific Th cell development. However, its role in CRSwNP remains to be defined. The aim of the present study was to investigate whether AhR, which regulates Th17 cell differentiation, played a role in the pathogenesis of CRSwNP by evaluating AhR expression in nasal polyps and peripheral blood mononuclear cells (PBMCs) obtained from CRSwNP patients. Forty-eight patients (atopic, 24; non-atopic, 24) and 13 controls were studied. To explore the role of AhR in CRSwNP, we analyzed the expression of AhR, retinoid-related orphan receptor C (RORC), interleukin (IL)-17, and IL-10 and the differentiation of Th17 using mRNA or protein detection methods. Notably, the expression of AhR was reduced in CRSwNP, and the expression of AhR was lower in the atopic group than in the non-atopic group. However, there was a very low level of Th17 and its associated factors (RORC, IL-17) in the control group compared to the two CRSwNP groups. In particular, the polarization of Th17 cells in atopic CRSwNP patients was increased compared with non-atopic individuals. In addition, ITE intervention in PBMCs promoted AhR expression and attenuated Th17 responses, demonstrating that AhR was more likely to suppress Th17 cells differentiation in Chinese CRSwNP patients. This information is valuable for obtaining a clear understanding of the pathogenesis of CRSwNP. Moreover, patients with atopic CRSwNP may exhibit reduced expression of AhR, leading to aggravation of the disproportionate distribution of Th17 cells in polyp tissues and PBMCs, thereby suggesting that atopic CRSwNP has a distinct pathogenesis from that of non-atopic CRSwNP.

FCRL3 Gene Polymorphisms Confer Autoimmunity Risk for Allergic Rhinitis in a Chinese Han Population.

Background Heredity and environmental exposures may contribute to a predisposition to allergic rhinitis (AR). Autoimmunity may also involve into this pathologic process. FCRL3 (Fc receptor-like 3 gene), a novel immunoregulatory gene, has recently been reported to play a role in autoimmune diseases. Objective This study was performed to evaluate the potential association of FCRL3 polymorphisms with AR in a Chinese Han population. Methods Five single-nucleotide polymorphisms of FCRL3, rs945635, rs3761959, rs7522061, rs10489678 and rs7528684 were genotyped in 540 AR patients and 600 healthy controls using a PCR-restriction fragment length polymorphism assay. Allele, genotype and haplotype frequencies were compared between patients and controls using the χ2 test. The online software platform SHEsis was used to analyze their haplotypes. Results This study identified three strong risk SNPs rs7528684, rs10489678, rs7522061 and one weak risk SNP rs945635 of FCRL3 in Chinese Han AR patients. For rs7528684, a significantly increased prevalence of the AA genotype and A allele in AR patients was recorded. The frequency of the GG genotype and G allele of rs10489678 was markedly higher in AR patients than those in controls. For rs7522061, a higher frequency of the TT genotype, and a lower frequency of the CT genotype were found in AR patients. Concerning rs945635, a lower frequency of the CC genotype, and a higher frequency of G allele were observed in AR patients. According to the analysis of the three strong positive SNPs, the haplotype of AGT increased significantly in AR cases (AR = 38.8%, Controls = 24.3%, P = 8.29×10-14, OR [95% CI] 1.978 [1.652~2.368]). Conclusions This study found a significant association between the SNPs in FCRL3 gene and AR in Chinese Han patients. The results suggest these gene polymorphisms might be the autoimmunity risk for AR.

Erratum to: Association study between interleukin-12 receptor β1/β2 genes and allergic rhinitis in the Chinese Han population

Interleukin-12 (IL-12) plays a key role in the protection against allergic reaction induced by allergen as well as the differentiation of T helper 1 cells in patients with allergic rhinitis (AR), exerting its biological effects through binding to specific IL-12 receptors (IL-12Rs) termed IL-12Rβ1 and IL-12Rβ2. In this study, we investigated the relationship between polymorphisms in the IL-12R gene and AR in the Chinese Han population. A total of 543 patients with AR and 749 normal controls were genotyped for IL-12Rβ1/rs438421, IL-12Rβ2/rs3790565, rs3790567, and rs6679356 using a PCR restriction fragment length polymorphism analysis. The association study of each polymorphism of the IL-12Rβ1 and IL-12Rβ2 gene and AR showed that a significantly increased prevalence of the homozygous rs438421 GG genotype and G allele appeared in the AR patients compared with healthy controls. A significantly decreased prevalence of AG in rs438421 in AR patients is compared with healthy controls. Our research demonstrated an important association between polymorphisms in IL-12Rβ1 and AR in the Chinese Han population. A strong association between rs438421 in a single nucleotide polymorphism of IL-12Rβ1 and AR was identified.

Allergen induced Treg response in the peripheral blood mononuclear cells (PBMCs) of patients with nasal polyposis.

BACKGROUND Nasal polyposis (NP) is a chronic inflammatory disease of the nasal cavity and sinuses regulated by T cells. Regulatory T (Treg) cells are involved in controlling immune responses and inhibiting the allergen-specific effector cell response. The aim of this study was to evaluate whether NP patients had defects in Treg cells after specific allergen exposure and the possible correlation between atopy and Treg cells. METHODS Peripheral blood mononuclear cells (PBMCs), isolated from NP patients and controls, were cultured with allergen+phytohemagglutinin (PHA) or PHA stimulation for 48h. The frequency of CD4+CD25+Foxp3+ cells was measured by flow cytometry. The level of Foxp3 was measured by Real-time PCR. Concentrations of Interferon-γ (IFN-γ), Interleukin-4 (IL-4), Interleukin-5 (IL-5), Interleukin-10 (IL-10) and transforming growth factor-β (TGF-β) in culture supernatants were determined by ELISA. RESULTS Both atopic and non-atopic NP patients had a significantly decreased frequency of Treg cells and Foxp3 level in allergen stimulated PBMCs, also significantly decreased TGF-β level in culture supernatants. The decrease was even more striking in the atopic group. Also, there were significantly negative correlations between Treg cells and IFN-γ, IL-4, IL-5. Moreover, inthe atopic group, allergen stimulation downregulated Treg cells and increased IFN-γ, IL-4, IL-5 levels, while upregulating Treg cells and decreasing IFN-γ, IL-4, IL-5 levels in controls. CONCLUSIONS Patients with NP have a defective Treg cell response after allergen stimulation which is related to excessive Th1 and Th2 responses to specific allergens. Atopy may increase the impairment of Treg and exacerbate NP through the defective suppression of Treg on Th1 and Th2.

Reciprocal roles of STAT3 and STAT5 in nasal polyposis.

PURPOSE Nasal polyposis (NP) is a chronic inflammatory disease that is characterized by increased populations of Th17 cells and impairment of Treg cells function in Chinese patients. Recent studies have shown that signal transducer and activator of transcription 3 (STAT3) and STAT5 are indispensable in the development and maintenance of Th17 and Treg cells. We investigated the roles of STAT3 and STAT5 in the imbalance of Th17 and Treg cells in NP. MATERIALS AND METHODS The levels of IL-6, IL-2, pSTAT3, pSTAT5, SOCS3, RORc, Foxp3, IL-17A, and TGF-β1 were measured in patients with atopic NP, patients with nonatopic NP, and controls. We also evaluated the local distribution of Th17 and Treg cells by double immunofluorescence staining and the correlations between activated STAT3/STAT5 and Th17/Treg cell development were assessed. RESULTS Increased levels of IL-6, pSTAT3, SCOS3, RORc, IL-17A, and CD4(+) RORc(+) cells, and decreased levels of IL-2, pSTAT5, Foxp3, TGF-β1, and CD4(+) Foxp3(+) cells were detected in both NP groups compared to controls (P < .05). The differences in all expression levels (except for IL-6) were significant between atopic and nonatopic patients (P < .05). There was a positive correlation between pSTAT3/pSTAT5 levels and Th17/Treg development and a negative correlation between SOCS3 and pSTAT3 in NP (P < 0.01). CONCLUSIONS The results suggest that STAT3 and STAT5 may function through the IL-6 and IL-2 pathways to play a role in the imbalance of Th17/Treg in NP. An even more exaggerated imbalance of Th17/Treg caused by atopy may be correlated to the improper ratio of activated STAT3/STAT5.

Genetic risk of TNFSF4 and FAM167A-BLK polymorphisms in children with asthma and allergic rhinitis in a Han Chinese population

Abstract Background: Asthma and allergic rhinitis (AR) frequently occur as comorbid diseases of the upper airways. Single-nucleotide polymorphisms (SNPs) in the TNFSF4 and FAM167A-BLK genes have recently been shown to be associated with various immune-related disorders. Objective: Our aim was to determine whether TNFSF4 or FAM167A-BLK polymorphisms confer genetic susceptibility to asthma and AR in a Han Chinese population. Methods: We performed a case–control study of 290 asthmatic children and 252 healthy controls. Nine SNPs in the TNFSF4 region (rs1234313, rs1234314, rs1234315, rsl 2039904, rs844648 and rsl 0912580) and the FAM167A-BLK region (rs2254546, rs13277113 and rs1600249) were detected using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. Results: This study revealed that three SNPs in TNFSF4 (rsl 234313, rsl 234314 and rsl 234315) and two SNPs in FAM167A-BLK (rs2254546 and rsl 600249) were significantly correlated with asthma and AR, while SNP rsl600249 was associated with asthma without allergic rhinitis as a risk factor. Further, we demonstrated synergistic effects between the TNFSF4 and FAM167A-BLK SNPs. Conclusion: This study supports that the SNPs in TNFSF4 and FAM167A-BLK may be involved in asthma and AR gene risk in the Han Chinese cohort.

High frequency of T helper type 9 cells in Chinese patients with allergic rhinitis.

BACKGROUND T helper type 9 cells (Th9) are the most recently discovered subset of Th cells, and are involved in the pathology of several autoimmune and allergic diseases. The significance of Th9 cells in allergic rhinitis (AR) in Chinese patients is unclear. OBJECTIVE The aim of this study was to investigate the possible role of Th9 cells in AR in Chinese patients. METHODS Th9 cells and related factors were assessed by measuring levels of interleukin-9 (IL-9), PU.1, interferon-regulatory factor 4 (IRF4), and numbers of Th9 cells. A Th9-polarized milieu was evaluated by determining the levels of IL-4 and transforming growth factor-β1 (TGF-β1). Disease severity was assessed by rhino-conjunctivitis quality of life questionnaires (RQLQ), visual analog scale scores (VAS), and peripheral eosinophils (EOS) count. RESULTS Levels of IL-4 and TGF-β1 were elevated in AR groups versus healthy controls (P < 0.05). Levels of IL-9, PU.1, IRF4, and the numbers of Th9 cells were also significantly higher in the AR groups (P < 0.05). Furthermore, positive correlations were identified between IL-9 levels and EOS expression, RQLQ, and VAS scores (P < 0.01). CONCLUSIONS Th9 cells and their relative factors were elevated in AR patients. Levels of Th9 polarization-related factors were much higher in AR patients, and the severity of disease was associated with a more severe Th9 response. These results suggest that AR patients present a favorable environment for Th9 differentiation, and that Th9 cells may play a crucial role in the pathology of AR in Chinese patients.