Su-Ling Hong

Impaired Balance of Th17/Treg in Patients with Nasal Polyposis

Nasal polyposis (NP) is a chronic inflammatory disease of the nasal cavity and sinuses that is regulated by T lymphocyte subsets. Imbalance of Th17/Treg has been considered critical in the development of inflammation and atopic reactions. To assess whether the balance of Th17/Treg is disrupted in patients with NP, we evaluated the distribution of Th17 and Treg cells among peripheral blood mononuclear cells (PBMCs) in atopic patients with NP, non‐atopic patients with NP and controls. We then determined mRNA levels of RORc and Foxp3 and protein levels of IL‐17, TGF‐β and IL‐10 in polyp tissue among the three groups. Finally, we investigated the correlation between Th17‐, Treg‐ and Th1‐, Th2‐related cytokines (INF‐γ, IL‐4, IL‐5). The results demonstrated that both atopic and non‐atopic patients with NP revealed significantly increased Th17 proportion and decreased Treg proportion in PBMCs, as well as significantly increased RORc and IL‐17 levels and decreased Foxp3 and TGF‐β levels in polyp tissue. Furthermore, these differences were significant between atopic and non‐atopic groups. The frequency of Treg in PBMCs was found to be negatively correlated with Th1 and Th2 cytokines in polyps. These results indicated that an impaired balance of Th17/Treg existed in patients with NP and was more severe in atopic patients, suggesting that the imbalance of Treg/Th17 may play an important role in the development of NP and that atopy may aggravate NP by promoting the imbalance of Th17/Treg.

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.

Transforming growth factor‐beta 1 pathways in inflammatory airway diseases

Transforming growth factor‐beta 1 (TGF‐β1) has been reported being involved in the remodeling and immunosuppression processes of inflammatory airway diseases; understanding the regulation of TGF‐β1 is therefore a key to unravel the pathomechanisms of these diseases. This review briefly summarizes the current knowledge on the influencing factors for driving TGF‐β1 and its regulatory pathways in inflammatory airway diseases and discusses possible therapeutic approaches to TGF‐β1 control. The factors include smoking and oxidative stress, prostaglandins (PGs), leukotrienes (LTs), bradykinin (BK), and microRNAs (miRs). Based on the summary, new innovative treatment strategies may be developed for inflammatory airway diseases with an impaired expression of TGF‐β1.

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.

Regulation of Transforming Growth Factor-β1 Activation and Expression in the Tissue Remodeling Involved in Chronic Rhinosinusitis

Transforming growth factor-β1 (TGF-β1) plays a key role in the tissue remodeling processes involved in chronic rhinosinusitis (CRS), with the biological functions of secreted TGF-β1 regulated by multiple proteins. Among these regulators, latency-associated peptide and latent TGF-β-binding protein inhibit TGF-β1 function, whereas different proteases and integrins activate it. Progress in understanding the factors responsible for the bioactivity and expression of TGF-β1 has revealed that the dysregulation of TGF-β1 activation and expression is closely associated with the chronic respiratory inflammatory diseases involved in CRS. This review of the regulation of TGF-β1 activation and expression provides insight into the mechanism responsible for the different CRS subtypes, which will help further the investigation of novel therapy targets for the treatment of CRS.

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.

Differential expression and release of activin A and follistatin in chronic rhinosinusitis with and without nasal polyps

Background Chronic rhinosinusitis with (CRSwNP) and without nasal polyps (CRSsNP) should be regarded as distinct clinical entities based on differential inflammatory mediator and remodeling profiles. Activin A, a member of the TGF-β superfamily, plays an important role in inflammation and remodeling in the lower airways, although its expression and release in the upper airways remain undescribed. Objective To investigate the expression of activin A and its inhibitor follistatin in nasal tissue samples from CRSsNP and CRSwNP patients, and to monitor the spontaneous release of these molecules in a human mucosal model. Methods Protein levels were determined using ELISA for activin A, follistatin, TGF-β1 and indicator proteins (IL-5, ECP, IFNγ) in 13 CRSsNP, 23 CRSwNP, and 10 control samples. The spontaneous release rate and the release ratios of activin A, follistatin and TGF-β1 were determined in 9 CRSsNP and 7 CRSwNP tissue fragments cultured ex-vivo. The induction of activin A and TGF-β1 by one another was studied in 7 CRSsNP tissue fragments cultured ex-vivo. Results Significantly higher concentrations of activin A, follistatin, TGF-β1, and IFNγ were observed in CRSsNP compared with CRSwNP samples, whereas the concentrations of IL-5 and ECP were significantly lower. Follistatin was positively and linearly correlated with activin A in CRSsNP and CRSwNP. Activin A, follistatin and TGF-β1 were all spontaneously released by the samples, although the relative ratios released by tissue fragments from CRSsNP and CRSwNP samples were significantly different, with a higher follistatin/activin A-ratio and a follistatin/TGFß1-ratio (with less overall TGF-β1) in CRSwNP than in CRSsNP. Furthermore, TGF-β1 enhanced activin A secretion in CRSsNP tissue fragments cultured ex-vivo. Conclusion The differences in tissue concentrations and spontaneous release rates for activin A and follistatin in different CRS samples support the hypothesis that CRSsNP and CRSwNP are two distinct disease entities with respect to remodeling patterns.

Repeated intranasal instillation with staphylococcal enterotoxin B induces nasal allergic inflammation in guinea pigs.

Background Staphylococcal enterotoxins (SEs) appear to play a role in the pathogenesis of allergic disease. However, no animal models have been reported to show nasal allergic inflammation by repeated inhalation with staphylococcal enterotoxin B (SEB) in the absence of adjuvant. This study was designed to determine whether intranasal instillation of guinea pigs with SEB results in nasal allergic inflammation. Methods Guinea pigs were intranasally instilled with 40 μL of 4-μg SEB once every 4 days 11 times. For the control group, guinea pigs were prepared with saline instead of SEB. Sneezing and nasal scratching frequency were evaluated after each intranasal instillation. The production of antigen-specific antibodies including IgE, nasal eosinophilia, and cytokines in the nasal cavity lavage fluid (NCLF) were measured after the 11th intranasal immunization. Results In the model group, symptoms of sneezing and nasal scratching were induced at the 8th to 11th challenges. Intranasal immunization with SEB elicited a local nasal mucosa inflammatory response characterized by apparent eosinophil infiltration. In the NCLF, the expression of IL-4 but not interferon-gamma was increased after challenges. The serum levels of total and SEB-specific IgE and IgG1 were higher in model groups in comparison with the control groups (p < 0.01). Conclusion These results indicate that repeated intranasal instillation with SEB leads to Th2 immune response, allergic nasal inflammation, and increased antigen-specific IgE production that are characteristic of allergic rhinitis (AR). The model in this study could be valuable in analyzing the pathogenesis of AR infected with Staphylococcus aureus.

MicroRNA expression profile of mature dendritic cell in chronic rhinosinusitis

ObjectiveChronic rhinosinusitis (CRS), which includes CRS without nasal polyposis (CRSsNP) and with nasal polyposis (CRSwNP), shows imbalance of helper T cells (Th) and regulatory T cells (Treg). The balance of Th and Treg cells is orchestrated by dendritic cells (DCs). Recent studies show functions of DCs can be regulated by microRNAs (miRNAs or miRs). This study is aimed to investigate miRNAs expression profiles of peripheral blood DCs in CRS.MethodsPeripheral blood samples of 30 patients with CRS and 7 patients with nasal septum deviation alone were collected. CD14+ monocytes were isolated from these samples and differentiated into dendritic cells (DCs). Small RNAs were extracted from mature DCs and reversely transcribed into cDNA by Mir-XTM miRNA First-Strand synthesis method. MiRNA microarrays were used for miRNA expression analysis. Microarray results were validated by real-time PCR performed on five top list target genes.ResultsMiRNA microarrays showed that DCs from different types of patients have different sets of differential expressed miRNAs when comparing with Controls; they also share 31 commonly changed miRNAs among all three groups of CRS patients. Of these 31 miRNAs, 5 miRNAs were up-regulated and 25 miRNAs were down-regulated in all three types of CRS, while MiR-1290 was down-regulated in CRSsNP but up-regulated in both atopic CRSwNP and non-atopic CRSwNP.ConclusionsBy comparing miRNA gene expression patterns in 3 types of CRS patients, we have been able to identify candidate miRNAs that might mediate the core pathogenesis of CRS through regulating dendritic cells. These miRNAs could serve as potential therapeutic targets for CRS.