Serum IL-17 levels in patients with allergic rhinitis

The prevalence and risk of allergic rhinitis in psoriasis patients: a systematic review and meta-analysis

Psoriasis, a chronic inflammatory systemic disease, may increase the risk of allergic diseases. This meta-analysis assesses the prevalence and risk of developing allergic rhinitis in psoriasis. We systematically searched MEDLINE, Scopus, and EMBASE for population-based studies documenting AR in psoriasis compared to those without from inception to December 2023. Meta-analysis was conducted using the random-effects model. Eight studies, comprising 5 cross-sectional studies, 1 case-control study, 1 retrospective cohort study, and 1 prospective cohort study, were included. The increased prevalence of AR was 22.29% (95% CI: 0.135 to 0.281; P < 0.001; I2 = 99.05%) in the psoriasis population. The AR risk in psoriasis was insignificant (adjusted OR 1.19%; 95% CI: 0.69 to 2.06; I2 = 99%; P < 0.00001). Subgroup analysis in moderate to severe psoriasis cases revealed a trend of higher risk of AR (OR 1.41%; 95% CI: 0.94 to 2.10; I2 = 92%; P = 0.0003) with very low certainty of evidence. High heterogeneity was observed in most analyses. Our meta-analysis demonstrated a higher prevalence of AR in psoriasis patients. Evaluating and treating allergic diseases can enhance holistic treatment.

Altered expression of long noncoding RNAs regulating neutrophilic inflammation in peripheral blood was associated with symptom severity in patients with house dust mite-induced allergic rhinitis

Background

Long noncoding RNAs (lncRNAs) have been implicated in a diverse array of human immune diseases; however, a comprehensive understanding of the expression and function of lncRNAs in the peripheral blood leukocytes of individuals suffering from house dust mite (HDM)-induced allergic rhinitis (AR) remains elusive.

Objective

To explore the potential roles and functions of long noncoding RNAs (lncRNAs) in the pathogenesis of AR.

Methods

Sequencing analysis was performed on peripheral blood leukocytes collected from patients with HDM-induced AR and healthy controls (HCs) to elucidate the expression patterns of lncRNAs. Differentially expressed (DE) lncRNAs were identified and validated, and further correlation analyses were conducted to explore their associations with visual analog scale (VAS) scores and cytokine levels in the serum and nasal secretions. Additionally, bioinformatics analyses were performed to predict the potential pathways influenced by DE lncRNAs. Finally, the diagnostic potential of these lncRNAs in AR was assessed via receiver operating characteristic (ROC) curve analysis.

Results

Significant differences in the expression profiles of lncRNAs and mRNAs were detected between AR patients and HCs. Four lncRNAs were markedly upregulated in AR patients. AC011524.2 was positively correlated with nasal pruritus (r = 0.4492, P = 0.0411). AL133371.3 was positively correlated with runny nose (r = 0.4889, P = 0.0245). AC011524.2 was positively correlated with CXCL8 (r = 0.4504, P = 0.0035). AL133371.3 was significantly positively correlated with only IL-17 (r = 0.4028, P = 0.0100). IL-4 in the serum was positively related to IL-17 in the serum (r = 0.4163, P = 0.0002). CXCL5 in the serum was positively correlated with IFN-γ (r = 0.3336, P = 0.0354) in nasal secretions. The area under the curve (AUC) of the ROC curve resulting from the integration of the 4 lncRNAs exhibited a remarkable value of 0.940 for AR diagnosis.

Conclusions

Our results identified several lncRNAs associated with AR symptoms and inflammatory cytokines. Specifically, AC011524.2 and AL133371.3 exhibited strong correlations with diverse AR manifestations and serum cytokines, suggesting their pivotal role in the pathogenesis of AR, likely via neutrophil- and Th17-related pathways. However, the precise underlying mechanisms are still elusive, necessitating further exploration.

The Impact of Cytokines on Health-Related Quality of Life in Adolescents with Allergic Rhinitis

BACKGROUND

Frequent episodes of nasal symptoms are the usual clinical manifestations (CM) of allergic rhinitis (AR) and have a significant negative impact on health-related quality of life (HRQoL) in adolescents. The purpose of this cross-sectional study was to test the hypothesis that cytokines in nasal mucus may be associated with HRQoL in adolescents with AR.

METHODS

European Quality of Life 5 Dimensions 3 Level Version (EQ-5D-3L), "The Adolescent Rhinoconjunctivitis Quality of Life Questionnaire" (AdolRQLQ) and the Total 4 Symptom Score (T4SS) scoring system were administered to 113 adolescents with AR, nonallergic rhinitis (NAR) and to healthy control subjects. Nasal secretions were sampled and tested for 13 cytokines using a multiplex flow cytometric bead assay.

RESULTS

The AR group had significantly lower EQ-5D-3L (0.661 ± 0.267 vs. 0.943 ± 0.088; p < 0.001) and higher AdolRQLQ total scores (2.76 ± 1.01 vs. 1.02 ± 0.10; p < 0.001) compared to the control group. The AR group had higher concentrations of IL-1β (p = 0.002), IL-6 (p = 0.031), IL-8 (p < 0.001), IL17-A (p = 0.013) and IL-18 (p = 0.014) compared to the control group, and IL-1β, IL-6, IL17-A and IL-18 were significantly (p < 0.050) increased with disease progression. Cytokines IL-1β, IL-6, as well as severe CM, were identified as significant predictors of lower HRQoL in adolescents with AR.

CONCLUSIONS

This study identified IL-1β, IL-6, as well as severe CM, as predictors of lower HRQoL in adolescents with AR. However, these results should only serve as a starting point for additional confirmation research.

The efficacy and safety of Yupingfeng Powder with variation in the treatment of allergic rhinitis: Study protocol for a randomized, double-blind, placebo-controlled trial

Background: Allergic rhinitis (AR) is an upper airways chronic inflammatory disease mediated by IgE, which affects 10%-20% of the population. The mainstay for allergic rhinitis nowadays include steroids and antihistamines, but their effects are less than ideal. Many patients therefore seek Chinese medicine for treatment and Yupingfeng Powder is one of the most common formulae prescribed. In this study, we aim to investigate the efficacy and safety of Yupingfeng Powder with variation for the treatment of allergic rhinitis. Study design: This is a double-blind, randomized, placebo-controlled trial. A 2-week screening period will be implemented, and then eligible subjects with allergic rhinitis will receive interventions of either "Yupingfeng Powder with variation" granules or placebo granules for 8 weeks, followed by post treatment visits at weeks 12 and 16. The change in the Total Nasal Symptom Score (TNSS) will be used as the primary outcome. Discussion: This trail will evaluate the efficacy and safety of Yupingfeng Powder in treating allergic rhinitis. The study may provide the solid evidence of Yupingfeng Powder with variation can produce better clinical efficacy than the placebo granules. Trial registration: ClinicalTrials.gov, identifier NCT04976023.

Role of IL-17 in atopy-A systematic review

PURPOSE OF REVIEW

Atopy is defined as the genetic predisposition to react with type I allergic diseases such as food-, skin-, and respiratory allergies. Distinct molecular mechanisms have been described, including the known Th2 driven immune response. IL-17A (IL-17) is mainly produced by Th17 cells and belongs to the IL-17 family of cytokines, IL-17A to F. While IL-17 plays a major role in inflammatory and autoimmune disorders, more data was published in recent years elucidating the role of IL-17 in allergic diseases. The present study aimed to elaborate specifically the role of IL-17 in atopy.

METHODS

A systematic literature search was conducted in MEDLINE, Embase, and Cochrane Central Register of Controlled Trials, regarding IL-17 and atopy/allergic diseases.

RESULTS

In total, 31 novel publications could be identified (food allergy n = 3, allergic asthma n = 7, allergic rhinitis [AR] n = 10, atopic dermatitis [AD] n = 11). In all allergic diseases, the IL-17 pathway has been investigated. Serum IL-17 was elevated in all allergic diseases. In AR, serum and nasal IL-17 levels correlated with the severity of the disease. In food allergies, serum IL-17E was also elevated in children. In AD, there is a trend for higher IL-17 values in the serum and skin specimen, while it is more expressed in acute lesions. In allergic asthma, serum IL-17 levels were increased. In two studies, higher serum IL-17 levels were found in severe persistent asthmatic patients than in intermittent asthmatics or healthy controls. Only one therapeutic clinical study exists on allergic diseases (asthma patients) using a monoclonal antibody against the IL-17 receptor A. No clinical efficacy was found in the total study population, except for a subgroup of patients with (post-bronchodilator) high reversibility.

SUMMARY

The role of IL 17 in the pathogenesis of allergic diseases is evident, but the involvement of the Th17 cytokine in the pathophysiological pathway is not conclusively defined. IL-17 is most likely relevant and will be a clinical target in subgroups of patients. The current data indicates that IL-17 is elevated more often in acute and severe forms of allergic diseases.

Lipid Profile and IL-17A in Allergic Rhinitis: Correlation With Disease Severity and Quality of Life

BACKGROUND

Recent data display the possible role of cytokines such as interleukin-10 (IL-10), IL-17 and IL-23 as a link between dyslipidemia and atopy; however, the relationship between dyslipidemia, allergic rhinitis (AR), and the underlying mechanisms involved is unclear.

PURPOSE

To measure the lipid profile and IL-17A level in AR patients in comparison to healthy controls, and correlate serum lipid level with the severity of symptoms and quality of life (QoL) of AR patients.

PATIENTS AND METHODS

Peripheral blood samples were collected from AR patients (n=70) and a control group (n=80). Samples were analyzed for serum total IgE by ELISA, serum lipid profile, and IL-17A level by ELISA. Severity of AR symptoms was assessed by visual analogue scale (VAS) score and the rhinoconjunctivitis QoL questionnaire.

RESULTS

Serum lipid profile and level of IL-17A in AR patients were significantly higher in comparison to controls (P < 0.001). Positive correlations were found between total cholesterol (TC) and the severity of AR and QoL. IL-17A was positively correlated with triglyceride (TG) level and low-density lipoprotein cholesterol (LDL-C) (P=0.011, r=0.303; P=0.043, r=0.242, respectively). Additionally, IL-17A was negatively correlated with high-density lipoprotein cholesterol (HDL-C) level (P=0.036, r=-0.251). IL-17A was positively correlated with both age and VAS score with statistical significance (P=0.033, r=0.225; P=0.011, r=0.302, respectively).

CONCLUSION

Dyslipidemia might play a potential role in the severity of AR symptoms and impairment of patients' QoL. Highlighting this association might alert physicians to evaluate the lipid profile in AR patients for timely diagnosis and treatment of dyslipidemia in an attempt to improve disease control and improve QoL.

Functional Genetic Polymorphisms in the IL1RL1-IL18R1 Region Confer Risk for Ocular Behçet's Disease in a Chinese Han Population

Single nucleotide polymorphisms (SNPs) in the IL1RL1–IL18R1 region are associated with various immune-mediated diseases. This study was carried out to investigate the causal variant for ocular Behçet’s disease (BD) and elucidate its target genes in the IL1RL1–IL18R1 region. Nine candidate functional SNPs were prioritized with bioinformatics analysis, followed by a two-stage association study in 694 ocular BD patients and 1,458 unaffected controls. Functional studies were performed in the peripheral blood mononuclear cells (PBMCs) of 45 healthy men and 16 active male BD patients. Genotyping was performed using the MassARRAY System. The mRNA expressions of IL1RL1, IL18R1, IL18RAP, and SLC9A4 were assayed by real-time PCR and secretion of cytokines was examined by ELISA. Significantly lower frequencies of the rs12987977 GG genotype/G allele (P_c = 8.93 × 10^–7, OR = 0.39; P_c = 2.60 × 10^–3, OR = 0.77, respectively), rs12999364 TT genotype/T allele (P_c = 3.15 × 10^–4, OR = 0.51; P_c = 1.13 × 10^–2, OR = 0.80, respectively), and rs4851569 AA genotype/A allele (P_c = 3.29 × 10^–4, OR = 0.52; P_c = 9.72 × 10^–3, OR = 0.80, respectively) were observed in BD patients compared with the controls. Functional experiments revealed a downregulation of IL1RL1, IL18R1, and SLC9A4 and a decreased secretion of IFN-γ in the anti-CD3/CD28 antibody-treated PBMCs as well as a decreased production of TNF-α in the lipopolysaccharide (LPS)-stimulated PBMCs in carriers of the protective homozygous rs12987977/GG genotype compared with the TT genotype. Our findings show that functional SNPs—rs12987977, rs12999364, and rs4851569—in the IL1RL1–IL18R1 region confer susceptibility to ocular BD in a Chinese Han population. And IL1RL1, IL18R1, and SLC9A4 may be the target genes of rs12987977.

The relationship between IL-17A and IL-22 expression and clinical severity in patients with moderate/severe persistent allergic rhinitis

PURPOSE

Several reactions leading to numerous effects are regulated by IL-22. However, the relationship between IL-22 and immunopathogensis of allergic rhinitis (AR) has been rarely investigated. The aim of the present study was to investigate the levels of IL-22 and IL-17A in AR patients and their association with clinical severity of persistent allergic rhinitis (PAR).

MATERIALS AND METHODS

Thirty mild persistent allergic rhinitis (M PAR) patients, thirty moderate/severe persistent allergic rhinitis (M/S PAR) patients, and thirty healthy controls were enrolled in this study. Local production of IL-22 and IL-17A in PAR patients and healthy controls' nasal mucosa was examined by immunohistochemistry (IHC) and real-time polymerase chain reaction (RT-PCR) techniques. Serum levels of IL-22, IL-17A, specific immunoglobulin E (sIgE), and total IgE (tIgE) in PAR patients and healthy controls were determined by ELISA. In addition, blood eosinophil, nasal eosinophils per field, and total nasal syndrome score (TNSS) were also assessed.

RESULTS

In comparison with healthy controls, production of IL-22 and IL-17A in M/S PAR patients increased significantly. Furthermore, serum levels as well as the mean number of IL-22+ and IL-17A+ cells in nasal mucosa correlated with sIgE, nasal eosinophil count, and TNSS.

CONCLUSION

The results of the present study provide the first evidence that local production of IL-22 might be expressed in PAR patients. The expression of IL-22 and IL-17A, and their correlations with clinical parameters in PAR patients suggest the role of these cytokines in the events involved in the development of PAR.

Mitochondrial ROS activate interleukin-1β expression in allergic rhinitis

Allergic rhinitis (AR) is the most common cause of inflammation of the nasal mucosa. It is also the most common form of non-infectious rhinitis associated with an immunoglobulin E (IgE)-mediated immune response against allergens. Previous studies have indicated that interleukin-1β (IL-1β) has a pathological role in the development of allergic asthma. The present study was designed to assess whether IL-1β participates in the pathogenesis of AR. A total of 45 patients with AR were enrolled in the present study and were identified to have increased IL-1β expression expressed by peripheral blood mononuclear cells (PBMCs), and the mitochondrial reactive oxygen species (ROS) and NLRP3 are required for IL-1β synthesis in monocytes/macrophages and PBMCs from patients with AR. The levels of IL-1β and interleukin-17 (IL-17) were increased in patients with AR and were positively correlated with each other. The results of the present study suggested that patients with AR have raised mitochondrial ROS levels, which may upregulate the expression of IL-1β, affecting IL-17-production and serving a role in the pathogenesis of AR.

Allergic Rhinitis and Its Relationship with IL-10, IL-17, TGF-β, IFN-γ, IL 22, and IL-35

BACKGROUND

We aimed in our study to research the role of new cytokines such as IL-35, IL-22, and IL-17 that may form a target for novel treatment approaches.

METHODS

IL-10, IL-17, TGF-β, IFN-γ, IL-22, and IL-35 serum levels of allergic rhinitis (AR) patients were measured using ELISA method. Allergic sensitization was demonstrated by the skin prick test. Patients only with olive tree sensitivity were evaluated for seasonal AR (SAR). Patients only with mite sensitivity were included in the study for perennial AR (PAR). AR clinic severity was demonstrated by the nasal symptom scores (NSS).

RESULTS

In total, 65 AR patients (patient group), having 31 PAR and 34 SAR patients, and 31 healthy individuals (control group) participated in the study. Cytokine levels between the patient group and the control group were compared; IL-17 (p = 0.038), IL-22 (p = 0.001), and TGF-β (p = 0.031) were detected as high in the patient group, and IFN-γ (p < 0.001) was detected as low in the patient group. When correlation analysis was made between age, gender, prick test result, NSS, AR duration, and cytokine levels in the patient group, a negative correlation was detected only between IFN-γ (p = 0.032/r = -0.266) level and NSS.

CONCLUSIONS

Accompanied by the literature information, these results made us think that T cell subgroups and cytokines have an important role in AR immunopathogenesis. It is thought that future studies to be conducted relating to this subject will form new targets in treatment.

A systematic review of the role of interleukin-17 and the interleukin-20 family in inflammatory allergic skin diseases

PURPOSE OF REVIEW

Allergic skin diseases include atopic dermatitis/eczema, contact dermatitis, and drug hypersensitivity. Allergic skin diseases have a high prevalence. Atopic dermatitis is one of the most common inflammatory skin diseases and similar for allergic rhinitis and allergic asthma. Over a long period, allergic diseases have been regarded as immunoglobulin E-mediated T-helper-2 (Th2)-driven. But new cytokines and T cells have been discovered within the last years. In this systematic review, the focus is laid on interleukin-17 (IL-17) and the interleukin-20 (IL-20) family which appear to be fine-tuning the Th2-driven answer.

RECENT FINDINGS

IL-17 is a proinflammatory cytokine, which is produced by T cells. Primarily, IL-17 is produced by activated CD4+ cells, called Th-17 cells. IL-17 regulates keratinocyte expression of adhesion molecules and chemokines. IL-17 is involved in the pathogenesis of inflammatory diseases as psoriasis, arthritis, and inflammatory bowel diseases. In allergic diseases, the involvement of the TH17/IL17-pathway has only been recently described. Regarding the IL-20 family, IL-22 is the most interesting and the most studied cytokine in terms of allergic inflammatory disorders. IL-22 is produced by T-helper 22 cells, a new subset of CD4+ cells.

SUMMARY

IL-17 as well as IL-22 seem to play a role in the pathogenesis of allergic skin diseases.

Serum IL-17 & eotaxin levels in asthmatic patients with allergic rhinitis

Objective:

To investigate the serum levels of Interleukin (IL)-17 and eotaxin levels and the relationship between serum IL-17, eotaxin and pulmonary function in asthmatic patients with allergic rhinitis.

Methods:

Serum IL-17 and eotaxin levels in asthmatic patients with allergic rhinitis during attacking and remission and in healthy control subjects were measured using enzyme-linked immunosorbent assay (ELISA) kits. Then we studied the correlation between the serum IL-17, eotaxin levels and pulmonary function in patients.

Results:

Serum IL-17 and eotaxin levels were significantly elevated in patients during asthma attack and remission compared with healthy control subjects. These levels in patients during asthma attack were much higher than those during remission. Furthermore, serum IL-17 and eotaxin levels were negatively correlated with pulmonary function in asthmatic patients with allergic rhinitis, respectively.

Conclusion:

Our findings suggest that IL-17 and eotaxin are important factors in asthma with allergic rhinitis, and the correlation between serum IL-17, eotaxin and lung function possibly lead to improvements in the diagnosis and treatment of asthma with allergic rhinitis and related diseases.

Interleukin-9 and interleukin-17C in chronic rhinosinusitis

BACKGROUND

Interleukin (IL)-9 and IL-17C have been known to play a role in allergic inflammation, yet, their roles in chronic rhinosinusitis (CRS) are not well defined. IL-9 induces changes in epithelial cell gene expression leading to goblet cell metaplasia, whereas IL-17C is functionally distinct in that its expression can be induced by bacterial challenge and inflammatory stimuli. This study aimed to compare levels of IL-9 and IL-17C in CRS with nasal polyps (CRSwNP) and without nasal polyps (CRSsNP) as well as atopy.

METHODS

Nasal polyp or sinus mucosal specimens from CRSwNP (n = 36), CRSsNP (n = 9), and control (n = 9) groups were collected and processed. Patient atopy status was determined by history of skin-prick test and pulmonary function test. Immunohistochemistry was carried out using anti-human IL-9 and IL-17C antibodies. Positively-stained cells were enumerated under high-power (×400) magnification in 5 consecutive fields.

RESULTS

The level of expression of IL-9 was higher in CRSwNP than CRSsNP and control. Similar findings were demonstrated in IL-17C with higher expression in CRSwNP than CRSsNP and control. Both the averages of positively-stained cells expressing IL-9 and IL-17C were higher in CRS with asthma and allergy compared to control. This suggested that IL-9 and IL-17C were both involved in the pathogenesis of CRS, allergy, and asthma.

CONCLUSION

Inflammatory cell expression of IL-9 and IL-17C were increased in CRS, particularly with allergy and asthma. These interleukins may contribute to the pathogenesis of CRSwNP as well as atopy and may serve as therapeutic targets for disease management.

Expression of IL-17A concentration and effector functions of peripheral blood neutrophils in food allergy hypersensitivity patients

Lymphocytes Th17 and other types of immune system cells produce IL17. By induction of cytokines and chemokines, the IL17 cytokine is involved in mechanisms of allergic reaction with participation of neutrophil granulocytes. It affects activation, recruitment, and migration of neutrophils to the tissues, regulating inflammatory reaction intensity. Excited neutrophils secrete inter alia elastase and reactive oxygen species (ROS)--significant mediators of inflammation process responsible for tissues damage.The aim of the study was to evaluate the concentrations of serum interleukin 17A, serum neutrophil elastase, and ROS production by neutrophils in patients with food allergy.The study included 30 patients with food allergy diagnosed based on interview, clinical symptoms, positive SPT, placebo controlled double-blind oral provocation trial, and the presence of asIgE in blood serum against selected food allergens using fluoro-immuno-enzymatic method FEIA UNICap 100. The control group consisted of 10 healthy volunteers. The concentrations of IL17A were determined in all patients using ELISA method with eBioscience kits, and elastase using BenderMed Systems kits. Chemiluminescence of non-stimulated neutrophils was evaluated using luminol-dependent kinetic method for 40 min on Luminoskan (Labsystems luminometer).The results of serum IL-17A concentrations and the values of chemiluminescence obtained by non-activated neutrophils, as well as elastase concentrations, were higher in patients with food allergic hypersensitivity compared to healthy volunteers.This study demonstrates a significance of IL-17A and activated neutrophil granulocytes in the course of diseases with food allergic hypersensitivity.

The paradigm of cytokine networks in allergic airway inflammation

PURPOSE OF REVIEW

Cytokines are immunomodulatory proteins important in cell signaling. Complex interactions of innate and adaptive immune cells, as well as structural cells and their cytokines, play crucial roles in regulating allergic airway inflammation. Here, we summarize current knowledge about the potential roles of known and newly identified helper T cells and epithelial cell-derived cytokines [interleukin (IL)-9, IL-17, IL-22, IL-25, and IL-33] in allergic rhinitis and asthma.

RECENT FINDINGS

Although T-helper (Th)2 cells were considered to be the main orchestrators of allergic airway inflammation, recent studies have revealed the potential interaction of other helper T cells and their cytokines in this process. Th17 cells may have a role in allergic rhinitis and asthma, and chronic rhinosinusitis with nasal polyps. An IL-9-producing subset called Th9 cells, Th22 cells which primarily secrete IL-22, IL-13, tumor necrosis factor-α, Th25 cells via producing IL-25 and epithelial cell-derived thymic stromal lymphopoietin, IL-33, IL-31, and IL-25 are believed to be important for the initiation of allergic reactions and inducing airway inflammation.

SUMMARY

A new paradigm of an interplay of cytokines is important in allergic rhinitis and asthma in orchestrating the allergic inflammatory response. Potential therapeutic applications emerging from the roles of these cytokines are promising, but need further research.

IL-23, rather than IL-17, is crucial for the development of ovalbumin-induced allergic rhinitis

Interleukin-23 (IL-23) and IL-17 are involved in the pathogenesis of allergic rhinitis (AR). However, the roles of IL-23 and IL-17 in ovalbumin (OVA)-induced AR remain unclear. Therefore in this study we aim to investigate the precise roles of IL-23 and IL-17 in a mouse model of OVA-induced AR. We found that during OVA-induced AR, eosinophil and goblet cells in the nose were significantly decreased in IL-23-deficient, but not in IL-17-deficient mice. However, there was no difference in the serum IgE and IgG1 levels between IL-23-deficient or IL-17-deficient and wild-type mice. Moreover, IL-4 levels in lymph node cell culture supernatants were significantly decreased in IL-23-deficient, but not IL-17-deficient, compared with wild-type mice. Furthermore, OVA-induced AR developed similarly in wild-type mice transferred with either IL-23-deficient BM cells or wild-type BM cells. These findings suggest that IL-23, but not IL-17 is crucial for the development of OVA-induced AR, and IL-23 neutralization may be a potential approach for treatment of OVA-induced AR in humans.

Cytokine profiles in allergic rhinitis

Allergic rhinitis, particularly seasonal allergic rhinitis, is considered a classic Th2-mediated disease, with important contributions to pathology by interleukins 4, 5 and 13. As such, allergic rhinitis is an excellent model for studying allergic inflammation, with findings potentially relevant to the mechanism of lower airways inflammation seen in allergic asthma. However, recent evidence has revealed roles for additional non-Th2 cytokines in asthma, including IL-17 family cytokines and epithelial-derived cytokines. Additionally, putative roles for epithelial-derived cytokines and innate lymphoid cells have been described in chronic rhinosinusitis with nasal polyps. Here, evidence for the involvement of different cytokines and cytokine groups in allergic rhinitis is considered.

Local expression of interleukin-17a is correlated with nasal eosinophilia and clinical severity in allergic rhinitis

Interleukin (IL)-17A is a major cytokine produced by Th17 cells, which are associated with chronic inflammations. The local expression of IL-17A in allergic rhinitis (AR) remains to be characterized. We sought to determine the role of IL-17A expression in human inferior turbinate mucosa in the pathophysiology of AR. Inferior turbinate mucosa was sampled from medical treatment–resistant, surgery-required patients with perennial AR (PAR, n = 21), nonallergic rhinitis with eosinophilia syndrome (NARES, n = 7), and nonallergic hypertrophic rhinitis (HR, n = 13). IL-17A expression was determined with immunohistochemical staining. The mean number of IL-17A⁺ cells and eosinophils per field were counted. Total serum immunoglobulin E (IgE) levels, blood eosinophil count, and forced expiratory volume in 1 second (FEV₁)/forced vital capacity (FVC) ratio were also examined in each patient. IL-17A was primarily expressed in infiltrating inflammatory cells. The number of IL-17A⁺ cells in nasal mucosa was significantly higher in the PAR group compared with HR (p = 0.002) and NARES (p = 0.021) groups. There was a significant and positive correlation between the number of IL-17A⁺ cells and total nasal symptom score (rho = 0.403; p = 0.011), especially sneezing score (rho = 0.471; p = 0.003). The number of IL-17A⁺ cells was significantly and positively correlated with the degree of eosinophil infiltration (rho = 0.623; p < 0.001), but not with total serum IgE levels (rho = 0.284; p = 0.098), blood eosinophil counts (rho = 0.302; p = 0.056), or FEV₁/FVC ratio (rho = 0.092; p = 0.569). The present study provides evidence that IL-17A expression in the nasal mucosa is associated with the pathophysiology of AR, including disease severity and nasal eosinophilia.

T cell transcriptional factors in allergic rhinitis and its association with clinical features

BACKGROUND

Th2 cells are crucially important in allergic disease and the possible involvement of Treg and Th17 cells has not been clearly identified.

OBJECTIVE

To identify the mRNA expression of T cell transcription factors in nasal mucosa in patients with allergic rhinitis (AR) and to reveal their correlations with clinical features.

METHODS

Eighteen patients with AR and 12 controls with turbinate hypertrophy were included. mRNA expression of the following transcriptional factors in nasal mucosa were measured by quantitative polymerase chain reaction; T-bet (Th1), GATA3 (Th2), retinoic acid-related orphan receptor C (RORC; Th17), and forkhead box P3 (Foxp3; Treg). mRNA expression was compared among groups and correlation between mRNA expression level and clinical features (rhinitis symptoms, eosinophil count, and IgE) were also investigated.

RESULTS

GATA3 and RORC were significantly increased and Foxp3 was significantly decreased in the AR group. Moderate-to-severe AR group also had increased expression of GATA3 and RORC than mild AR group, suggesting severity of AR influence expression of transcription factors. Correlation analysis showed that none of these transcription factors were associated with severity of clinical symptoms, eosinophil counts and skin prick test severity and that IgE level was significantly correlated with expression level of GATA3 and RORC, suggesting an association of IgE production with Th2 and Th17 cells.

CONCLUSION

Increased mRNA expression of GATA3 (Th2), increased expression of RORC and decreased expression of Foxp3 may be important in pathogenesis of AR. GATA3 and RORC may be closed related with IgE level.

Th22 and related cytokines in inflammatory and autoimmune diseases

INTRODUCTION

Th22 and related cytokines regulate various processes and have been linked to diverse effects. The levels of Th22 and cytokine IL-22 are increased in several disorders and positively related to some autoimmune diseases. Preclinical studies have suggested that the inhibition or stimulation of IL-22 is an attractive approach to reverse the immune disorders. Simultaneously, considering many patients with refractory autoimmune diseases respond poorly to the therapies which are highly toxic, more effective therapies are to be examined.

AREAS COVERED

The role of Th22 cells and related cytokines and therapeutic strategies targeting them in many illnesses, especially inflammatory and autoimmune diseases.

EXPERT OPINION

Th22 cells and related cytokine IL-22 regulate multiple biological functions and play an important role in a number of inflammatory and autoimmune diseases. They have unique and attractive advantages for targeting. Targeting IL-22 has already been trialed in many mice experiments, showing better efficacy and fewer side effects compared with classical drugs. Targeting IL-22 or Th22 might provide pathogenetic treatment. However, Th22 subset is a recently identified Th subset and its associated research is extremely limited. Therefore, there are still many unanswered questions and further researches are warranted.

Differences in airway inflammation according to atopic status in patients with chronic rhinitis

Background

Chronic rhinitis is a heterogeneous group of diseases that cause nasal inflammation. And the nose may be a window into the lung in the concept of "one airway one disease."

Objective

This study was conducted to evaluate differences between the different forms of chronic rhinitis in terms of lower airway inflammation.

Methods

Patients that attended the allergy clinic and presented with moderate/severe persistent rhinitis symptoms for more than 1 year were enrolled. The patients with chronic rhinitis were classified into two groups (house dust mites [HDM]-sensitive allergic rhinitis [AR] or non-allergic rhinitis [NAR]) according to the presence of atopy, and additionally according to nasal polyposis and airway hyperresponsiveness, respectively. Medical records were reviewed and the mRNA expression levels of IL-5, IFN-γ, TGF-β1, IL-17A, and IL-25 were evaluated in induced sputum samples in each group.

Results

Induced sputum samples of 53 patients were evaluated. Patients with NAR were significantly older than patients with HDM-sensitive AR (p < 0.05). Nasal polyposis was more prevalent in NAR patients than in HDM-sensitive AR patients (10.2% vs. 62.5%, p < 0.001). The expression levels of IL-17A mRNA were higher in NAR patients, regardless of the presence of airway hyperresponsiveness (p = 0.005).

Conclusion

These results suggest that patients with different forms of chronic rhinitis could have different inflammatory environments in their lower airway and NAR patients might have bronchial inflammation related to the elevated levels of IL-17A compared to HDM-sensitive AR patients.

Thirty-year survey on airborne pollen concentrations in Genoa, Italy: relationship with sensitizations, meteorological data, and air pollution

BACKGROUND

Pollen allergy represents a relevant health issue. Betulaceae sensitization significantly increased in Genoa, Italy, in the last decades. This study investigated possible relationships among pollen count, meteorological changes, air pollution, and sensitizations in this city during a 30-year period.

METHODS

Betulaceae, Urticaceae, Gramineae, and Oleaceae pollen counts were measured from 1981 to 2010 in Genoa. Sensitization to these pollens was also considered in large populations of allergic patients. Meteorological parameters and pollutants were also measured in the same area.

RESULTS

Betulaceae sensitization increased over time. All pollen species significantly increased over this time. Pollen season advanced for Betulaceae and Urticaceae. Only Urticaceae season significantly increased. Temperature increased while rainfall decreased over the time. Pollutants significantly decreased. There were some relationships between pollen changes and climatic and air pollution parameters.

CONCLUSION

This 30-year study conducted in an urbanized area provided evidence that Betulaceae sensitization significantly increased, pollen load significantly augmented, and climate and air pollution changed with a possible influence on pollen release.

Th22 in inflammatory and autoimmune disease: prospects for therapeutic intervention

T helper cell 22 (Th22) is a new subset of T cells clearly separate from Th17 and other known T cell subsets with distinct gene expression and function. With the CCR6 + CCR4 + CCR10 + phenotype and aryl hydrocarbon receptor as the key transcription factor, Th22 subsets produce cytokines such as IL-22, whose function depends on the activation of signal transduction and activators of transcription 3. IL-22 was up-regulated in Rheumatoid arthritis, Crohn's disease, Psoriasis, and atopic dermatitis patients whereas it was down-regulated in the serum of patients with sarcoidosis and systemic lupus erythematosus. Furthermore, it has been demonstrated that IL-22 may have promise as a potential therapeutic for chronic inflammatory diseases, and treatment with recombinant cytokine or gene therapy delivery of IL-22 may alleviate tissue destruction during inflammatory responses. In summary, Th22 cell plays an important and complicated role in inflammatory and autoimmune disease.

IL-22 mRNA in peripheral blood mononuclear cells from allergic rhinitic and asthmatic pediatric patients

T helper (T(H) )-17 lymphocytes are characterized by the expression of many regulatory cytokines, including IL-17A and IL-22, but at present no clinical data are available on the expression of these cytokines in peripheral blood mononuclear cells (PBMC) from allergic asthmatic and rhinitic (AR) children. The aim of this study was to investigate a possible relationship between IL-22 and IL-17A mRNAs and clinical parameters in seroatopic, AR, and asthmatic children. The study, conducted during the pollen season, included 18 healthy and 18 allergic (n=9 asthmatic and n=9 rhinitic) children. Serum total and specific IgE, eosinophil count, and skin prick test were performed; in addition, IL-22 and IL-17A mRNA levels were detected in PBMC from healthy and allergic subjects by quantitative real-time PCR. Despite the absence of the mRNA for the IL-17A cytokine, IL-22 expression was found in PBMC from asthmatic patients, with increased IL-22 mRNA levels in patients with chronic severe respect to those with moderate asthma. A positive correlation between IL-22 mRNA and serum total IgE levels was found in asthmatic children. In addition, higher IL-22 and IL-17A mRNA levels were detected in both AR and asymptomatic seroatopic children, compared to healthy individuals, and a correlation between IL-22 and IL17A mRNA and serum total IgE levels was demonstrated. Moreover, the mRNA level of retinoic acid-related orphan receptor C, the T(H) 17 transcription factor, was found to be increased in AR but not in asthmatic patients. This study provides the first evidence that IL-22 mRNA might be expressed in chronic severe asthmatic and AR children. The expression of IL-22 and IL-17A mRNAs in asymptomatic monosensitized seroatopic children suggests a role of these cytokines in the early events involved in the development of these allergic diseases.

Antibody and cytokine responses to house dust mite allergens and Toxoplasma gondii antigens in atopic and non-atopic Brazilian subjects

According to hygiene hypothesis, a lower exposure to infection is associated with increased prevalence of allergic diseases. This study aimed to investigate the association between atopy and Toxoplasma gondii (Tg) infection by analyzing the antibody and cytokine responses to house dust mite allergens and T. gondii antigens in Brazilian subjects. A total of 275 individuals were assessed and divided into atopics (n=129) and non-atopics (n=146) based on markers of allergy (positive skin prick test and ELISA-IgE to mite allergens) or Tg-seropositive (n=116) and Tg-seronegative (n=159) groups according to infection markers (positive ELISA-IgG to T. gondii). Tg-seropositive individuals presented lower allergenic sensitization (37%) to mite allergens than Tg-seronegative subjects (54%). A significant association was found between atopy and negative serology to T. gondii (OR: 2.0; 95% CI: 1.23-3.26; P<0.05). Proliferative responses and cytokine production after antigenic stimulation showed predominant synthesis of Th1-cytokines as IFN-gamma in Tg-seropositive patients, whether atopics or non-atopics. Conversely, Th2-cytokines as IL-5 prevailed in atopics compared to non-atopics, regardless the seropositivity to T. gondii. Levels of IL-10, IL-13, IL-17, and TGF-beta were not able to discriminate the groups. Hence, a negative association between atopy and infection by T. gondii was demonstrated for the first time in Brazilian subjects, focusing on the antibody and cytokine responses and indicating that the immunomodulation induced by the parasite may play a protective role in the development of allergic diseases.

Certainties and doubts about sublingual and oral immunotherapy in children

PURPOSE OF REVIEW

Sublingual (SLIT) and oral immunotherapy (OIT) are two variants of immunotherapy that might be especially of interest for children. After adult studies, lately many trials in children are published. However, the quality of published material varies. In the present review we analyze paediatric SLIT publications from the past 2 years in the light of a new system of evaluation of quality of evidence, the grading of recommendations assessment, development and evaluation system.

RECENT FINDINGS

High quality evidence in children: high-dose daily grass SLIT reduces symptoms and medication use; low-dose pollen SLIT reduces the development of new sensitizations. Low-dose SLIT reduces symptoms and medication in mild-moderate atopic dermatitis. Latex SLIT for 3 years results in a negative glove test. The evidence for the effectiveness of SLIT for seasonal and perennial asthma is still of moderate-low quality, as is the evidence for asthma prevention. Too high dose of mite SLIT seems ineffective for asthma. Oral allergen immunotherapy is promising for some food allergies. Some definite immunological changes are seen with SLIT; facilitated antibody presentation and IL-17 might correlate with efficacy.

SUMMARY

Even after a hundred years of immunotherapy, it is still an ever changing field with SLIT and OIT making fast progress.

Opposing roles of IL-17A and IL-25 in the regulation of TSLP production in human nasal epithelial cells

BACKGROUND

The importance of IL-17A, IL-17F, and IL-25 in allergic rhinitis (AR), as well as their possible role in regulation on thymic stromal lymphopoietin (TSLP) production in nasal epithelial cells, is not well understood.

OBJECTIVE

To determine the possible regulation of IL-17A, IL-17F, and IL-25 on TSLP production in the initiation of allergic responses.

METHODS

The levels of IL-17A, IL-17F, IL-25, and TSLP in nasal lavages of patients with AR were measured using an enzyme-linked immunosorbent assay (ELISA) and compared with that in normal controls. Then, primary human nasal epithelial cells (HNECs) were stimulated with dsRNA (0-75 microg/ml), as well as IL-17A (100 ng/ml), IL-17F (100 ng/ml), and IL-25(100 ng/ml). The mRNA expression of IL-17A, IL-17F, IL-25, TSLP, as well as the chemokines CCL20, IL-8, and eotaxin was analyzed using quantitative real-time PCR, and their protein levels in the supernatants of cultured HNECs were determined by ELISA.

RESULTS

Both TSLP and IL-17 cytokines are significantly elevated in patients with AR. dsRNA was found to increase the production of IL-17F, IL-25, TSLP, CCL20, and IL-8 in HNECs. Furthermore, IL-25 significantly enhanced dsRNA-induced TSLP production in primary HNECs and was dominant to the inhibitory effect of IL-17A on TSLP regulation.

CONCLUSIONS

Our study provides the first evidence that both IL-17F and IL-25 can be induced by dsRNA in HNECs. Despite of the opposing effects of IL-17A and IL-25 on TSLP regulation in HNECs, IL-25 was dominant to IL-17A, providing a plausible explanation for the simultaneous upregulation of IL-17 cytokines and TSLP in patients with AR.

Peripheral Th-17 cells in allergic rhinitis: New evidence

BACKGROUND

Th17 is a subset of T helper lymphocytes exerting inflammatory activities. Recently, it has been reported that serum IL-17 levels are high in patients with severe birch allergy.

AIM OF THE STUDY

It was to compare the cytokine profile and the frequency of peripheral allergen-specific T helper producing IL-17 in patients with allergic rhinitis.

METHODS

Twelve patients with persistent allergic rhinitis due to pollens and 5 healthy non-allergic subjects were evaluated during the pollen season. Th17 were evaluated by intracellular staining in T cell compartment ex-vivo and after short activation by allergens and control antigens.

RESULTS

Ex-vivo PBMNC evaluation showed that allergic patients had higher frequencies of IL-17 producing T cells. Functional analysis after antigen-specific CD4+ T cell expansion demonstrated that allergic patients had higher frequencies of IL-17 producing T cells than normal subjects.

CONCLUSION

This preliminary study contributes to the knowledge concerning the possible role of Th-17 cells in the response to allergens.

Clinical outcome and IL-17, IL-23, IL-27 and FOXP3 expression in peripheral blood mononuclear cells of pollen-allergic children during sublingual immunotherapy

Induction of allergen-specific, tolerogenic, IL-10 and/or TGF-β-producing T-regulatory (Treg) cells that express transcription factor FOXP3 is considered as one of the key mechanisms of allergen-specific immunotherapy. However, little is known of the induction of FOXP3 expression in children during sublingual immunotherapy (SLIT). Recently, also, a novel subgroup of T-helper (Th) cells, the Th17 cells, secreting predominantly IL-17 (IL-17A), was identified. The expressions of IL-17 or the Th17-regulating cytokines IL-23 and IL-27 during SLIT are currently completely unexplored. This randomized, placebo-controlled dose-response study was performed to analyze the effects of SLIT on FOXP3, IL-17, IL-23, and IL-27 expressions in peripheral blood mononuclear cells (PBMC) of children with allergic rhinitis and their associations with clinical outcome. Thirty children were included: ten received SLIT with a glycerinated mixture of birch, hazel and alder with a cumulative weekly dose of 24,000 SQ-U, 10 with dose 200,000 SQ-U/wk, and ten received placebo. Cytokine and FOXP3 mRNA expressions in allergen-, purified protein derivative-stimulated and non-stimulated PBMC were determined at 0, 1 and 2 yr of SLIT by real-time RT-PCR (TaqMan). Symptoms and medications were recorded using diary cards. Allergen-induced IL-17 mRNA expression was significantly increased in the study subjects with elevated combined Symptom Medication Score (SMS) after 2 yr. There was also a significant positive correlation between the allergen-induced IL-17 and SMS in whole study group (r = 0.38, p = 0.039) and especially the 200,000 SQ-U dose-treated group (r = 0.74, p = 0.027) at 2 yr. Allergen-induced FOXP3 mRNA expression was significantly increased in the 200,000 SQ-U dose-treated children after two study years as compared with baseline (p = 0.016) and placebo-treated children (p = 0.028). The changes in FOXP3 mRNA expression positively correlated with IL-10 and TGF-β mRNAs during SLIT in whole study population. Increased allergen-induced IL-17 responses during SLIT are associated with elevated SMS. Increased tolerogenic, allergen-specific Treg responses are also observed in children during SLIT.

Peripheral TH-17 cells in children with allergic rhinitis: preliminary report

Th17 is a subset of T helper lymphocytes and exerts pro-inflammatory activities. Recently, it has been reported that serum IL-17 levels are high in the most severe patients with birch allergy studied both outside and during the pollen season. This study aims to compare the frequency of peripheral IL-17-producing T cells in children with allergic rhinitis and in healthy controls. Ten children with allergic rhinitis and 5 healthy non-allergic subjects were evaluated. Th17 were evaluated by intracellular staining in ex-vivo T cell compartment. Ex- vivo PBMNC evaluation showed that allergic patients had higher frequencies of IL-17 producing T cells, both concerning CD4+ and CD8+ cells. In particular, there is a subset co-expressing IL-17 and IFN-gamma both for CD4+ and CD8+ cells. In conclusion, this preliminary study suggests a possible role of Th-17 cells in the response to allergens in children.

Interleukin 17 and RANTES levels in induced sputum of patients with allergic rhinitis after a single nasal allergen challenge

BACKGROUND

Interleukin 17 (IL-17) is produced by T(H)17 cells and was recently implicated in the development of the T(H)2 cell response. RANTES (regulated on activation of normal T cells expressed and secreted), among other chemokines, plays a crucial role in chemotaxis of eosinophils into airway mucosa. According to the "united airway" hypothesis, markers of inflammation in allergic diseases are elevated in the upper and lower airways.

OBJECTIVE

To assess the impact of a single nasal allergen challenge on IL-17 and RANTES levels in induced sputum of patients with allergic rhinitis (AR).

METHODS

Eighteen patients with a history of AR due to grass pollen confirmed by positive skin prick test results and 10 control subjects entered the study. Initially, all the patients underwent sputum induction. A single nasal placebo challenge was performed 24 hours later, with repeated sputum induction 24 hours after challenge. After 4 weeks of washout, these procedures were repeated with allergen challenge. Differential cell counts in sputum were determined, and concentrations of IL-17 and RANTES were measured by means of enzyme-linked immunosorbent assay.

RESULTS

Levels of IL-17 and RANTES significantly increased in sputum of patients with AR after allergen (but not placebo) challenge (P = .03 and P = .007, respectively). Postallergen levels of both cytokines in sputum were positively correlated (r = 0.570, P = .02). Allergen challenge led to increased total inflammatory cell (P = .005) and eosinophil (P = .03) counts in induced sputum of patients with AR.

CONCLUSIONS

Nasal allergen challenge induces the enhanced secretion of IL-17 and RANTES in the lower airways of nonasthmatic patients with AR.

TGF-beta and IL-17 serum levels and specific immunotherapy

Two new T cell subsets may be involved in allergic rhinitis (AR) pathogenesis: Th17 and T regulatory cells, mainly producing IL-17 and TGF-beta respectively. Successful Sublingual Immunotherapy (SLIT) induces relevant immunological changes, thus the aim of this study was to evaluate serum IL-17 and TGF-beta levels in AR patients treated with SLIT for 2 years. Patients' blood samples were collected before initiating SLIT (baseline), three months after the end of the first pre-seasonal SLIT course, and at the end of the second pre-seasonal course. IL-17 was detectable only in the most severe allergic patients. SLIT significantly induced an increase in serum TGF-beta levels. There was moreover a significant relationship between TGF-beta and symptom severity and drug use at the end of the study. Therefore, this study provides clinically relevant evidence that two pre-seasonal SLIT courses may significantly affect serum TGF-beta levels.

Increased serum interleukin 17 in patients with systemic lupus erythematosus

Interleukin 17 (IL-17) is a Th17 cytokine associated with inflammation, autoimmunity and defense against some bacteria, it has been implicated in many chronic autoimmune diseases including psoriasis, multiple sclerosis and systemic sclerosis. However, whether IL-17 plays a role in the pathogenesis of systemic lupus erythematosus (SLE) remains unclear. In the present study, we aimed to investigate the serum IL-17 level in patients with SLE and it's associations with disease manifestations and activity. Fifty-seven patients with SLE and 30 healthy volunteers were recruited. Serum IL-17 levels were examined by enzyme linked immunosorbent assay (ELISA). Statistic analyzes were performed by SPSS 10.01. Results show that serum IL-17 levels were significantly elevated in SLE patients as compared with normal controls. Nevertheless, no associations of serum IL-17 level with clinical and laboratory parameters were found; no significant difference regarding serum IL-17 level between SLE patients with nephritis and those without nephritis was found; no significant difference was found between Less active SLE and More active SLE; Correlation analysis between serum IL-17 levels and SLEDAI showed no association. Taken together, our results indicate increased serum IL-17 levels in SLE patients, suggesting that this cytokine may trigger the inflammatory process in SLE. However, no associations of serum IL-17 level with disease manifestations were found. Therefore, further studies are required to confirm this preliminary data.