Expression Of IL-17RB Research Articles

IL17RB expression is associated with malignant cancer behaviors and poor prognosis in oral cancer.

Previously, we demonstrated that IL17RB plays an essential role in lung cancer progression. This study aimed to determine whether IL17RB correlates with oral cancer and promotes oral cancer progression. IL17RB expression in oral cancer tissues and normal tissues was determined by immunohistochemistry staining, while the association of IL17RB expression with the clinicopathological characteristics of oral squamous cell carcinoma (OSCC) patients was analyzed and its correlation with progression-free survival and response to radiotherapy and chemotherapy in OSCC patients was also explored. Western blotting was performed to investigate the expression of IL17RB in various OSCC cell lines; moreover, transwell assay was performed to evaluate the effect of IL17RB expression on cell migration ability. In this study, we found that IL17RB was expressed higher in OSCC tissues compared to normal oral mucosa tissues and its expression was positively correlated with tumor size, lymph node metastasis, advanced cancer stage, and poor prognosis. In vitro study showed that IL17RB expression in OSCC cell lines as determined by Western blotting, was positively correlated with their migration ability. Clinical and in vitro studies suggest that IL17RB might serve as an independent risk factor and a therapeutic target for oral cancer.

IL17RB and IL17REL Expression Are Associated with Improved Prognosis in HPV-Infected Head and Neck Squamous Cell Carcinomas.

Changes in the cellular secretome are implicated in virus infection, malignancy, and anti-tumor immunity. We analyzed the association between transcriptional signatures (TS) from 24 different immune and stromal cell types on the prognosis of HPV-infected and HPV-free head and neck squamous carcinoma (HNSCC) patients from The Cancer Genome Atlas (TCGA) cohort. We found that HPV-positive HNSCC patients have tumors with elevated immune cell TS and improved prognosis, which was specifically associated with an increased tumor abundance of memory B and activated natural killer (NK) cell TS, compared to HPV-free HNSCC patients. HPV-infected patients upregulated many transcripts encoding secreted factors, such as growth factors, hormones, chemokines and cytokines, and their cognate receptors. Analysis of secretome transcripts and cognate receptors revealed that tumor expression of IL17RB and IL17REL are associated with a higher viral load and memory B and activated NK cell TS, as well as improved prognosis in HPV-infected HNSCC patients. The transcriptional parameters that we describe may be optimized to improve prognosis and risk stratification in the clinic and provide insights into gene and cellular targets that may potentially enhance anti-tumor immunity mediated by NK cells and memory B cells in HPV-infected HNSCC patients.

IL-25 directly modulates adipocyte function and inflammation through the regulation of adiponectin.

This study aimed to investigate the direct role of IL-25 in modulating adipocyte function during homeostasis and low-grade inflammation induced by lipopolysaccharide (LPS). The 3T3-L1 preadipocyte cell lines and primary cultures of adipose-derived stromal vascular precursor cells of wild-type and IL-17RB-deficient mice were used to determine the direct function of IL-25. The expression of IL-17RB in differentiating adipocyte was determined using real-time PCR and flow cytometry analysis. The effect of IL-25 on lipid accumulation, triglyceride content, lipolysis, glucose uptake, and adipokine expression in the mature adipocytes was evaluated. IL-25 modulating the expression of inflammatory cytokines in adipocytes induced by low dose LPS was determined using real-time PCR and ELISA. The receptor for IL-25 was up-regulated during adipocyte differentiation and IL-25 directly modulated adipocyte function by reducing lipid accumulation and triglyceride concentration and enhancing lipolysis without affecting an insulin-stimulated glucose uptake. Interestingly, IL-25 induced adiponectin secretion through the PI3K/AKT signaling pathway. In 3T3-L1 adipocytes under low-grade inflammation, IL-25 attenuated the expression of IL-6 and CCL5 through the induction of adiponectin. Our studies suggest that IL-25 directly regulates adipocyte function by maintaining the adiponectin level during homeostasis and by alleviating inflammatory response through the regulation of adiponectin during low-grade inflammation in adipocytes.

Gene Expression Profile of Stromal Factors in Cancer-Associated Fibroblasts from Prostate Cancer

Recent investigations point at the stromal microenvironment to assess additional diagnostic information and provide new therapeutic targets in cancer. The aim of the study was to contribute to the characterization of the phenotype of cancer-associated fibroblasts (CAFs) in prostate cancer (PCa) compared with normal prostate-associated fibroblasts (NAFs) and fibroblasts from benign prostatic hyperplasia (BPH). Three patient populations were prospectively recruited: 23 patients with new localized PCa, 14 patients with advanced PCa treated with androgenic deprivation therapy (ADT), and 7 patients with BPH. Gene expression of 20 stroma-derived factors, including the androgen receptor (AR), chaperones (HSPA1A and HSF1), growth factors (FGF2, FGF7, FGF10, HGF, PDGFB, and TGFβ), proteins implicated in invasion (MMP2, MMP9, and MMP11), inflammation (IL6, IL17RB, NFκB, and STAT3), and in-stroma/epithelium interaction (CDH11, CXCL12, CXCL14, and FAP), was evaluated. Localized PCa CAFs showed a significant higher expression of FGF7, IL6, MMP2, and MMP11 compared with NAFs or IL17RB compared with BPH fibroblasts, but significantly lower expression of FGF10 and IL17RB compared with NAFs or CXCL14 compared with BPH fibroblasts. In addition, CAFs from ADT-resistant PCa showed significantly higher MMP11 and NFκB but significant lower TGFβ expression compared with CAFs from ADT-sensitive tumors. Our results contribute to defining the CAFs phenotypes associated to PCa progression, which may contribute to the diagnosis and design of alternative therapies in PCa.

MicroRNA-155-5p modulates the progression of acute respiratory distress syndrome by targeting interleukin receptors

ABSTRACT Acute respiratory distress syndrome (ARDS) is a multifactorial inflammatory lung failure with a high incidence and a high cost burden. However, the underlying pathogenesis of ARDS is still unclear. Recently, microRNA has been shown to have critical function in regulating the pathogenesis of ARDS development and inflammation. To identify the important microRNA in the serum from patients with ARDS that may be potential biomarkers for the disease and explore the underlying disease mechanism. We found significant upregulation of miR-155-5p expression in serum samples from patients with ARDS compared with the control group (p < 0.01). The levels of interleukin receptors and inflammatory cytokines were significantly increased in blood samples from patients with ARDS (p < 0.05). In the cell model, miR-155-5p had a binding site in the 3’-UTR of the three interleukin receptors. In LPS-simulated BEAS-2B cells, transfection of miR-155-5p mimic inhibited the expression levels of these interleukin receptors, and was found to directly target the inflammatory response of leukocyte nodulin receptor through NF-kB signaling. In conclusion, miR-155-5p can alleviate LPS-simulated injury that induces the expression of IL17RB, IL18R1, and IL22RA2 by affecting the NF-kB pathway; however, it cannot change the occurrence of inflammatory storms. Collectively, this suggests that the progression of ARDS is the result of effects of the multiple regulatory pathways, providing novel evidence for the therapy of ARDS.

IL-17B/RB Activation in Pancreatic Stellate Cells Promotes Pancreatic Cancer Metabolism and Growth.

Simple SummaryPancreatic cancer has the lowest survival rate of all malignancies. Understanding the interplay between tumor and stroma could lead to the development of new therapies. The metabolic role of interleukin 17B/interleukin 17B receptor (IL-17B/RB) has not been adequately studied in pancreatic cancer and is poorly understood. Here, we investigate the IL-17B/RB-mediated interactions between the tumor and the stroma. We analyze murine as well as human stromal and tumor cells, animal experiments with immunocompromised mice, and human cell lines with overexpression and knockdown of IL-17RB. We report that aberrant expression of IL-17B/RB in stromal pancreatic stellate cells (PSCs) accelerates tumor cell growth. IL-17B/RB-signaling supplies energy by increased oxidative phosphorylation (OXPHOS). Blocking IL-17B/RB to inhibit the tumor to stroma crosstalk could be a potential targeted therapy for pancreatic cancer.In pancreatic ductal adenocarcinoma (PDAC), the tumor stroma constitutes most of the cell mass and contributes to therapy resistance and progression. Here we show a hitherto unknown metabolic cooperation between pancreatic stellate cells (PSCs) and tumor cells through Interleukin 17B/Interleukin 17B receptor (IL-17B/IL-17RB) signaling. Tumor-derived IL-17B carrying extracellular vesicles (EVs) activated stromal PSCs and induced the expression of IL-17RB. PSCs increased oxidative phosphorylation while reducing mitochondrial turnover. PSCs activated tumor cells in a feedback loop. Tumor cells subsequently increased oxidative phosphorylation and decreased glycolysis partially via IL-6. In vivo, IL-17RB overexpression in PSCs accelerated tumor growth in a co-injection xenograft mouse model. Our results demonstrate a tumor-to-stroma feedback loop increasing tumor metabolism to accelerate tumor growth under optimal nutritional conditions.

P66.05 Correlation Between Expression of Immune Cell-Related Molecular Markers and Prognosis in Small Cell Lung Cancer (SCLC)

Current retrospective studies have found that the prognosis of patients with small cell lung cancer (SCLC) after surgical resection varies greatly. At present, the biological factors relevant to tumor immune microenvironment (TIME) that affect the prognosis of patients with SCLC remain to be explored. Content of 22 types of immune cells in TIME was estimated by CIBERSORT in a public dataset containing 77 postoperative SCLC patients. Correlation of each type of immune cells with overall survival (OS) was analyzed by univariate and multivariate Cox regression analysis. Vital cytokines and their receptors which correlated with gamma delta T cells (γΔT) and resting NK cells whose abundance significantly influence OS derived from public data analysis were detected at transcriptional level in tissue samples of 48 prognosis-based paired SCLC patients in our institute. Markers of activated NK cells, T cells, B cells, and immune effector molecules were also detected. Each marker was fitted into univariable Cox regression model. Molecular markers correlated with resting NK cells and γΔT and molecules whose coefficient reached statistical significance in univariate analysis were combined with clinicopathological factors for multivariate survival analysis. Univariate Cox regression analysis for external dataset showed that high relative proportion of follicular helper T cells (Tfh) is protective for OS (HR 1.30e-05, 95% CI: 3.2e-09-0.52, P = 0.008), while high relative proportion of γ Δ T cells (HR 4e+03, 95% CI 6.5-2.5e+06, P=0.011) and resting NK cells (HR 1.2e+10, 95% CI 200-7.5e+17, P=0.011) were hazardous for OS. Significant distinct disease-free survival (DFS) and OS was observed between the two paired groups in our internal cohort (DFS: P=1.00e-12; OS: P=2.05e-09), but there was no significant difference in clinical characteristics such as age, gender, clinical stage, treatment methods between the two groups. However, it was found that the expression of IL17RB was significantly higher in the poor prognosis group (P=0.015), while the expression of interferon γ(IFNG) and perforin (PRF1) was significantly lower in the poor prognosis group (IFNG: P=0.045; PRF1: P=0.013). Univariable Cox regression analysis confirmed that high expression of IL17RB was hazardous for shorter DFS, while high expression of activating receptor of NK cells (NCR1, NKG7), markers of effector T cells (CD8A) and cytotoxic molecules (PRF1, GZMB, GZMH) and IFNG were favorable for DFS. Among these molecules, influence on OS was also significant for NKG7, PRF1 and GZMB. Multivariable Cox regression analysis combining clinicopathological and immunological factors identified high expression of IL6 mRNA was hazardous for both DFS and OS independent of clinicopathological factors. Abundance of NK cells and T cells in TIME significantly affected the postoperative DFS of SCLC patients. Content of NK cells in TIME also significantly influenced OS of resected SCLC patients. The prognosis of patients with high expression of IL6 and IL17RB mRNA was extremely dismal, which might be explained by impairment of NK cell activity and γΔT polarization.

POS0326 ROLE OF THE IL-25 / IL-17RB AXIS IN TH9 POLARIZATION IN PATIENTS WITH PROGRESSIVE SYSTEMIC SCLEROSIS

Background:Systemic sclerosis (SSc) is an inflammatory connective tissue disease leading to chronic and progressive fibrosis, typically affecting the skin and internal organs. The alteration of both innate and adaptive immune responses plays a pivotal role in SSc pathophysiology, although it has not yet been fully elucidated [1].Recent findings have demonstrated interleukin (IL)-9 overexpression and significant group 2 innate lymphoid cells (ILC2) expansion in patients with SSc. Th9-ILC2-mast cells axis seems to be involved in SSc tissue damage and in the induction of fibrosis [2]. Activation and production of IL-9 by Th9 cells are promoted by transforming growth factor (TGF)-β, thymic stromal lymphopoietin (TSLP), IL-25 and IL-33. Thus, the IL-25 / IL-17RB pathway would act as a key player in SSc.Objectives:The purpose of this study was to evaluate the role of the IL-25 / IL-17RB axis as a driver in Th9 polarization and ILC2 expansion and polarization in SSc patients.Methods:26 patients were enrolled in this study. Peripheral blood and skin biopsy specimens were obtained from SSc patients. PBMCs were isolated and incubated with and without recombinant (r)IL-25 for 24-48-72 hours and the frequencies of Th9 cells, Th17 cells and ILC2 were assessed by flow cytometry analysis. Moreover, the ex vivo expression of IL-17RB in ILC2 was also assessed. Immunofluorescence analysis was performed on biopsy skin samples to evaluate IL-17RB expression in ILC2.Results:In SSc samples, Th9 cells frequency progressively increased after stimulation with rIL-25, compared to healthy controls in which IL-9 frequency decreased over time regardless of rIL-25.Simultaneously, we evaluated the role of the IL-25 / IL-17RB axis in Th17 cells.In the SSc pool, the initially low rate of IL-17 increased at 72 hours after stimulation with rIL-25. In unstimulated SSc samples, the initially higher IL-17 rate decreased at 72 hours; conversely, it was consistently low in healthy controls, at both baseline and stimulated conditions.Our results confirmed the presence of IL-25-dependent clonal ILC2 expansion, suggesting a greater and progressive expansion over time in patients with SSc, compared to controls.Interestingly, increased IL-17RB expression was found in circulating ILC2 from SSc patients supporting the characterization of ILC2 inflammatory phenotype.Consistently, immunofluorescence on the skin of SSc patients showed a marked infiltrate of CD3-GATA3+ IL-17RB+ cells, confirming the presence of the activated inflammatory phenotype ILC2, absent in skin biopsies of healthy controls (Figure 1).Conclusion:These preliminary data suggest an active role of the IL-25/IL-17RB axis in SSc. It results in Th9 polarization and Th17 clonal expansion, inducing the production of IL-9 and, to a lesser extent, IL-17. Moreover, in addition to promoting Th9-mediated ILC2 differentiation, IL-25 directs the polarization of ILC2 towards the inflammatory phenotype.

The mobilization effect of IL-25 on eosinophil progenitor cells in allergic asthma

Objective: Eosinophil progenitor cells (EoP) play a critical role in allergic airway inflammation in asthma. Previous studies have revealed that the expression of IL-25 receptor subunits (IL-17RA and IL-17RB) are increased on eosinophils (Eos) from allergic asthmatics upon allergen inhalation but few study has explored the role of IL-25 on EoP. Thus, in this research we examined the possible role of IL-25 on EoP in allergic asthmatics challenged by allergen, as well as in animal models where we verified the changes of newly produced Eos after IL-25 knockout. Methods: Asthmatics (n=14, during 2017-2018) who developed allergen-induced early and late responses were enrolled in this study. Blood was collected at pre-and 24 h post-challenge. Surface expression of IL-17RA and IL-17RB were evaluated by flow cytometry on EoP. In vitro migration assay was used to examine migrational responses of EoP and hematopoietic cells (HPC) from these subjects. In animal models, mice were grouped according to whether IL-25 was knock-out and whether mice were sensitized and challenged by ovalbumin (OVA) into asthmatic, control, knockout asthmatic and knockout control groups. Lung tissues, bronchoalveolar lavage flow (BALF) and bone marrow tissues of these mice were collected in order to evaluate airway inflammation and amount of newly produced (Brdu positive) and mature Eos. Results: EoP expressing IL-17RB were significantly increased after allergen inhalation in allergic asthmatics [(514±138) vs. (1146±450)/10(6) cells, pre-and post-challenge, F=6.819, P=0.022]. Pre-exposure to IL-25 primed the migrational responsiveness of EoP to stromal cell-derived factor (SDF)1α [(39.0±10.1)% vs. (73.0±7.9)%, control and IL-25 exposure groups respectively, P=0.021, 95% CI 5.19%~58.45%]. In OVA sensitized mice, knockout of IL-25 significantly reduced Eos and newly produced Eos percentage in the BALF [Eos, (7.8±2.0)% vs. (3.1±0.6)%, asthmatic and knockout asthmatic group respectively, P=0.002, 95% CI-7.57% to -1.98%; Brdu positive Eos, (50.0±7.6)% vs. (8.6±4.3)%, asthmatic and knockout asthmatic group respectively, P=0.011, 95% CI-72.41% to -10.27%], and newly produced Eos were also reduced in the bone marrow [(70.8±6.1)% vs. (1.3±1.3)%, asthmatic and knockout asthmatic group respectively, P=0.000, 95% CI -94.88% to -44.18%]. Conclusion: These results suggest an important role of IL-25 in allergen-induced EoP migration, local differentiation and eosinophilia in the airways.

Elevated expression of IL-17RB and ST2 on myeloid dendritic cells is associated with a Th2-skewed eosinophilic inflammation in nasal polyps

BackgroundInterleukin(IL)-25, IL-33, and thymic stromal lymphopoietin (TSLP) underlie the crosstalk between epithelial cells and dendritic cells (DCs) during the development of Th2 responses. This study aimed to measure the expressions of IL-17RB, ST2 and TSLPR, receptor of IL-25, IL-33, and TSLP respectively, on myeloid DCs in nasal polyps (NP) and evaluate their association with local Th2 inflammation and disease severity in patients with NP.MethodsSamples were collected from 30 NP patients and 16 control subjects recruited prospectively. The mRNA expression of cytokines, including TSLP, IL-25 and IL-33, as well as interferon (IFN)-γ, IL-4, IL-5, IL-13 and IL-17A in NP and control tissues was examined by qualitative polymerase chain reaction (qPCR). The expression of IL-17RB, ST2 and TSLPR as well as other surface markers on myeloid DCs (mDCs) was examined by flow cytometry.ResultsIncreased numbers of total and activated mDCs were found in NP patients. mDCs demonstrated significantly higher expression of IL-17RB, ST2 and TSLPR than those in control tissues. The activated mDCs exhibited up-regulations of OX40L and ICOSL, but down-regulation of PDL1 in NP. Moreover, the IL-17RB, ST2 and TSLPR levels on mDCs were positively correlated with IL-25, IL-33 and TSLP mRNA levels, respectively, in NP. Furthermore, IL-17RB and ST2 expressions on mDCs were correlated with the IL-5 mRNA level as well as eosinophil number in NP. Importantly, the IL-17RB expression on mDCs and the OX40L expression on activated mDCs in NP were positively correlated with CT score and total nasal symptom score.ConclusionsIncreased expressions of IL-17RB and ST2 on mDCs are associated with enhanced local Th2 inflammation in NP, suggesting that mDCs might play a role in IL-25- and IL-33-induced type 2 responses and eosinophilic inflammation in NP.

A positive feedback loop of IL-17B-IL-17RB activates ERK/β-catenin to promote lung cancer metastasis

Inflammation contributes to the development and progression of cancer. Interleukin-17 (IL-17) is an inflammatory cytokine that functions in inflammation and cancer, as well as several other cellular processes. In this study, we investigated the roles and the prognostic value of IL-17 and the IL-17 receptor (IL-17R) in lung cancer. Gene expression microarray analysis followed by Kaplan-Meier survival curve showed that IL-17B was associated with poor patient survival, and IL-17B receptor (IL-17RB) was up-regulated in lung cancer tissue compared with normal tissue. Expression of IL-17RB was associated with lymph node metastasis and distant metastasis, as well as poor patient survival. IL-17RB overexpression significantly increased cancer cell invasion/migration and metastasis in vitro and in vivo. IL-17RB induced ERK phosphorylation, resulting in GSK3β inactivation and leading to β-catenin up-regulation. IL-17RB also participated in IL-17B synthesis via the ERK pathway. IL-17RB activation is required for IL-17B-mediated ERK phosphorylation. Taken together, IL-17B-IL-17RB signaling and ERK participate in a positive feedback loop that enhances invasion/migration ability in lung cancer cell lines. IL-17RB may therefore serve as an independent prognostic factor and a therapeutic target for lung cancer.

Interleukin-25 and eosinophils progenitor cell mobilization in allergic asthma

BackgroundEosinophil-lineage committed progenitor cells (EoP) migrate from the bone marrow and differentiate locally to provide an ongoing source of mature eosinophils in asthmatic inflammatory responses in the airways. Sputum levels of EoP are increased in asthmatics compared to normal controls suggesting an exaggerated eosinophilopoietic environment in the airways. Understanding what factors promote EoP traffic to the airways is important to understand the diathesis of asthma pathology. Interleukin (IL)-25, is an epithelial-derived cytokine that promotes type 2 inflammatory responses. We have previously shown that levels of IL-25 and expression of the IL-25 receptor (IL-17RA and IL-17RB) on mature eosinophils are greater in allergic asthmatics compared to atopic non-asthmatics and non-atopic normal controls. In addition, these levels were increased significantly increased following allergen inhalation challenge and physiologically relevant levels of IL-25 stimulated eosinophil degranulation, intracellular IL-5 and IL-13 expression and primed migration to eotaxin. The current study, examined the role of IL-25 on allergen-induced trafficking of EoP in atopic asthmatics.MethodsAsthmatics (n = 14) who developed allergen-induced early and late responses were enrolled in the study. Blood was collected at pre- and 24 h post-challenge. At each time point, surface expression of IL-17RA and IL-17RB on EoP was evaluated by flow cytometry. Migration assays examined the effect of IL-25 on EoP chemotactic responses, in vitro. In addition, IL-25 knockout ovalbumin (OVA) sensitized and challenged mice were studied to evaluate in vivo mobilization effects of IL-25 on newly formed EoP and mature eosinophils.ResultsThere was a significant increase in numbers of blood EoP expressing IL-17RB, 24 h post-allergen inhalation challenge in allergic asthmatics. Pre-exposure to IL-25 primed the migrational responsiveness of EoP to stromal cell-derived factor 1α. In OVA-sensitized mice, knocking out IL-25 significantly alleviated OVA-induced eosinophil infiltration in the airway and newly formed eosinophils were reduced in the lung.ConclusionsThe findings of this study indicate a potential role for IL-25 in allergen-induced trafficking of EoP to the airways and local differentiation promoting tissue eosiniophilia in asthmatic responses.

Allergen-Induced Increases in Interleukin-25 and Interleukin-25 Receptor Expression in Mature Eosinophils from Atopic Asthmatics

Background: Interleukin (IL)-25 plays a pivotal role in type 2 immune responses. In a baseline cross-sectional study, we previously showed that IL-25 plasma levels and IL-25 receptor (IL-25R: IL-17RA, IL-17RB, and IL-17RA/RB) expression on mature blood eosinophils are increased in atopic asthmatics compared to normal nonatopic controls. This study investigated allergen-induced changes in IL-25 and IL-25R expression in eosinophils from asthmatics. Methods: Dual responder atopic asthmatics (n = 14) were enrolled in this randomized diluent-controlled crossover allergen challenge study. Blood was collected before and 24 h after the challenge. The surface expression of IL-25R was evaluated by flow cytometry on eosinophils and Th2 memory cells. In addition, plasma levels of IL-25 were measured by ELISA, and functional responses to IL-25 including type 2 cytokine expression, degranulation, and the migrational responsiveness of eosinophils were evaluated in vitro. Results: Following the allergen but not the diluent inhalation challenge, significant increases in the expression of IL-17RB and IL-17RA/B were found on eosinophils but not on Th2 memory cells. IL-25 plasma levels and the number of eosinophils but not of Th2 memory cells expressing intracellular IL-25 increased significantly in response to the allergen but not the diluent challenge. Stimulation with physiologically relevant concentrations of IL-25 in vitro caused (i) degranulation of eosinophils (measured by eosinophil peroxidase release), (ii) enhanced intracellular expression of IL-5 and IL-13, and (iii) priming of eosinophil migration to eotaxin. IL-25 stimulated intracellular cytokine expression, and the migration of eosinophils was blocked in the presence of a neutralizing IL-25 antibody. Conclusions: Our findings suggest that the IL-25/IL-25R axis may play an important role in promoting the recruitment and proinflammatory function of eosinophils in allergic asthma.

IL-25 Receptor Expression on Airway Dendritic Cells after Allergen Challenge in Subjects with Asthma.

IL-25 is an epithelial-derived cytokine, whose effects are mediated by the IL-25 receptor (IL-17RB), and that has been implicated in the pathogenesis of allergic disease and airway viral responses. Airway myeloid dendritic cells (mDCs) and plasmacytoid dendritic cells (pDCs) are professional antigen-presenting cells. pDCs may play a protective role in asthma and are key players in the innate immune response through recognition of microbial products via Toll-like receptors (TLRs). The effects of inhaled allergens on the expression of IL-17RB by mDCs and pDCs, and the effects of IL-25 on pDCs, are unknown. To evaluate allergen-induced changes in IL-17RB expression by mDCs and pDCs and to investigate the effects of IL-25 on pDCs. Patients with mild atopic asthma (n = 13) were challenged with inhaled allergen. Blood and sputum DCs were enumerated and IL-17RB expression was determined by flow cytometry before and 7 and 24 hours after allergen challenge. The effects of IL-25 on pDCs in vitro were also assessed. Inhaled allergen significantly increased mDC and pDC numbers in sputum but not in blood. The percentage of IL-17RB(+) mDCs and pDCs was significantly increased in blood and sputum 24 hours after challenge. IL-25 up-regulated TLR9 expression by pDCs and orchestrated the responses to TLR9 ligation. IL-17RB is up-regulated on blood and sputum mDCs and pDCs after allergen inhalation. IL-25 modulates pDC function through an effect on TLR9 expression.

IL-25 and IL-33 induce Type 2 inflammation in basophils from subjects with allergic asthma.

BackgroundThe alarmin cytokines IL-25 and IL-33 are key promoters of type 2 inflammation. Basophils respond to alarmin cytokines, however the relationship of these cytokines with basophil activation and recruitment in human studies of allergic asthma has not been well characterized. This study investigated the effect of IL-25 and IL-33 on basophils in a model of allergic asthma.Methods10 mild allergic asthmatics underwent allergen and diluent inhalation challenges. Bone marrow aspirates were collected at pre-challenge and 24 h (h) post challenge. Peripheral blood and sputum samples were collected at pre-challenge, 7 h, and 24 h post-challenge to measure basophil expression of IL-17RB, ST2, and intracellular IL-25. Freshly isolated peripheral blood basophils from allergic donors were incubated overnight with IL-25 and IL-33, or sputum supernatant collected post-allergen to assess pro-inflammatory effects of mediators released in the airways.ResultsThere were increased percentage of basophils expressing IL-17RB, ST2, and intracellular IL-25 collected from bone marrow, peripheral blood, and sputum after allergen inhalation challenge. In vitro stimulation with IL-25 and IL-33 increased the percentage of basophils expressing intracellular type 2 cytokines and surface activation markers, and primed eotaxin-induced migratory potential of basophils, which was mediated directly through IL-17RB and ST2, respectively. Stimulation of basophils with sputum supernatants collected post-allergen challenge up-regulated the percentage of basophils expressing markers of activation and intracellular type 2 cytokines, which was reversed following blockade of the common β chain (βc).ConclusionsOur findings indicate that the alarmin cytokines IL-33 and IL-25 increase basophil activation and migratory potential, and may pose as a novel therapeutic targets for the treatment of allergic asthma.Electronic supplementary materialThe online version of this article (doi:10.1186/s12931-016-0321-z) contains supplementary material, which is available to authorized users.

A critical role for IL-17RB signaling in HTLV-1 tax-induced NF-κB activation and T-cell transformation

Human T-cell leukemia virus type 1 (HTLV-1) infection is linked to the development of adult T-cell leukemia (ATL) and the neuroinflammatory disease HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP). The HTLV-1 Tax protein functions as a potent viral oncogene that constitutively activates the NF-κB transcription factor to transform T cells; however, the underlying mechanisms remain obscure. Here, using next-generation RNA sequencing we identified the IL-25 receptor subunit IL-17RB as an aberrantly over expressed gene in HTLV-1 immortalized T cells. Tax induced the expression of IL-17RB in an IκB kinase (IKK) and NF-κB-dependent manner. Remarkably, Tax activation of the canonical NF-κB pathway in T cells was critically dependent on IL-17RB expression. IL-17RB and IL-25 were required for HTLV-1-induced immortalization of primary T cells, and the constitutive NF-κB activation and survival of HTLV-1 transformed T cells. IL-9 was identified as an important downstream target gene of the IL-17RB pathway that drives the proliferation of HTLV-1 transformed cells. Furthermore, IL-17RB was over expressed in leukemic cells from a subset of ATL patients and also regulated NF-κB activation in some, but not all, Tax-negative ATL cell lines. Together, our results support a model whereby Tax instigates an IL-17RB-NF-κB feed-forward autocrine loop that is obligatory for HTLV-1 leukemogenesis.

A critical role for IL-17RB signaling in HTLV-1 tax-induced NF-κB activation and T-cell transformation.

Human T-cell leukemia virus type 1 (HTLV-1) infection is linked to the development of adult T-cell leukemia (ATL) and the neuroinflammatory disease HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP). The HTLV-1 Tax protein functions as a potent viral oncogene that constitutively activates the NF-κB transcription factor to transform T cells; however, the underlying mechanisms remain obscure. Here, using next-generation RNA sequencing we identified the IL-25 receptor subunit IL-17RB as an aberrantly overexpressed gene in HTLV-1 immortalized T cells. Tax induced the expression of IL-17RB in an IκB kinase (IKK) and NF-κB-dependent manner. Remarkably, Tax activation of the canonical NF-κB pathway in T cells was critically dependent on IL-17RB expression. IL-17RB and IL-25 were required for HTLV-1-induced immortalization of primary T cells, and the constitutive NF-κB activation and survival of HTLV-1 transformed T cells. IL-9 was identified as an important downstream target gene of the IL-17RB pathway that drives the proliferation of HTLV-1 transformed cells. Furthermore, IL-17RB was overexpressed in leukemic cells from a subset of ATL patients and also regulated NF-κB activation in some, but not all, Tax-negative ATL cell lines. Together, our results support a model whereby Tax instigates an IL-17RB-NF-κB feed-forward autocrine loop that is obligatory for HTLV-1 leukemogenesis.

IL-25 and IL-25 Receptor Expression on Eosinophils from Subjects with Allergic Asthma

Background: Allergic asthma is an inflammatory airway disease in which Th2 cytokines play an important role. Epithelial-derived interleukin (IL)-25 has been suggested to be important in the maintenance of Th2-type responses. The effects of IL-25 are mediated by the IL-25 receptor, composed of two subunits, IL-17RA and IL-17RB. Eosinophils are effector cells in allergic asthma. The role of IL-25 in eosinophil function is unknown. This study examined the expression of IL-25 and its receptor on eosinophils in allergic asthmatics compared to atopic nonasthmatics and normal controls. Methods: The expression of IL-25, IL-17RA and IL-17RB on eosinophils, and levels of plasma IL-25 were measured in 14 normal control subjects, 15 atopic nonasthmatics and 14 mild allergic asthmatics. Results: The expression of IL-17RB on eosinophils was significantly higher in allergic asthmatics (43.08%, range 33.96-59.98%) than in atopic nonasthmatics (11.98%, range 6.33-27.11%, p = 0.002) and normal controls (17.70%, range 10.97-38.9%, p = 0.01). IL-17RA expression was also significantly higher in the allergic asthmatic group. No differences were observed in the intracellular expression of IL-25. The concentration of IL-25 in plasma was significantly increased in the allergic asthmatics (145 ng/ml, range 64-290 ng/ml) when compared to the normal controls (21 ng/ml, range 0-116 ng/ml, p = 0.012), but not compared to atopic nonasthmatics. There was a significant negative correlation between FEV₁ % predicted and the IL-25 level in the plasma (r = -0.443, p = 0.003). Conclusions: The increased IL-25 levels in plasma and the expression of IL-17RA and IL-17RB on eosinophils in allergic asthma patients suggests that IL-25 may activate eosinophils during allergic inflammation.

Neutrophils produce interleukin-17B in rheumatoid synovial tissue

T helper 17 (Th17) and mast cells produce IL-17A in RA and critically contribute to the pathogenesis of RA. However, the complete IL-17 cytokine profile in RA is unknown. The aim of the study was to systematically study the expression of IL-17 family cytokines in RA. The expression of all IL-17 cytokines in RA synovium and pannus as well as in the synovium of OA was determined using quantitative RT-PCR (qRT-PCR). IL-17A and IL-17B were immunostained. Peripheral blood neutrophils were analysed for IL-17B. The effect of IL-17B alone or in combination with TNF-α was tested in vitro on fibroblasts and endothelial cells. In all tissues IL-17B was the most expressed IL-17 family cytokine, found in lining but most strongly expressed in human neutrophil elastase containing polymorphonuclear cells. This pattern was distinct from that of IL-17A, which was found in mast cell tryptase immunoreactive cells. Circulating neutrophils contained IL-17B, verifying the in vivo results. Fibroblasts up-regulated the expression of IL-17RB, a putative receptor of IL-17B, after TNF-α stimulation. IL-17B significantly enhanced TNF-α-induced production of G-CSF and IL-6 in fibroblasts. IL-17B, which is present in synovium, may contribute to the pathogenesis of RA. IL-17B can enhance the effects of TNF-α on the production of cytokines and chemokines that control immune cell trafficking and neutrophil homeostasis in the inflamed tissues.

Regulation of Th9-Type Pulmonary Immune Responses

Regulation of Th9-Type Pulmonary Immune Responses