Chronic Rhinosinusitis with Polyps Is Characterized by Increased Mucosal and Blood Th17 Effector Cytokine Producing Cells

Neutrophil Extracellular Traps as a Biomarker in Refractory Non-Type 2 CRSwNP

PURPOSE

Chronic rhinosinusitis (CRS) is classified into type 2 (T2) and non-T2 inflammation. T2 CRS presents as a severe form, CRS with nasal polyps (CRSwNP), which often occurs with asthma as a comorbidity worldwide. Some cases of non-T2 CRS show nasal polyposis and refractoriness, mainly in Asian countries. However, its mechanism remains elusive. To investigate a biomarker for the refractoriness of non-T2 CRSwNP via RNA sequencing.

METHODS

RNA sequencing by using nasal polyps (NPs) and ethmoidal mucosa (EM) from CRS subjects and uncinate tissues from controls was performed, and differentially expressed genes (DEGs) were analyzed (cutoffs: expression change > 2-fold, P < 0.01). Immunofluorescence staining and enzyme-linked immunosorbent assay were performed.

RESULTS

We identified DEGs among T2-NP, non-T2-NP, T2-EM, non-T2-EM, and controls (NP vs. controls: 1,877 genes, EM vs. controls: 1,124 genes, T2-NP vs. controls: 1,790 genes, non-T2-NP vs. controls: 2,012 genes, T2-EM vs. controls: 740 genes, non-T2-EM vs. controls: 1,553 genes). The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that neutrophil extracellular trap (NET) formation, systemic lupus erythematosus, and the phagosome were enriched in non-T2-NP vs. controls and non-T2-EM vs. controls. Immunofluorescence staining confirmed that NETs were elevated in non-T2-NP. Cytokine analysis demonstrated that NETs were significantly related to the refractoriness in non-T2-NPs.

CONCLUSIONS

This study demonstrated DEGs between T2 and non-T2 inflammation. These results suggest that NETs may contribute to the refractoriness in non-T2-NPs and have a promise as a therapeutic strategy for patients with refractory non-T2-NP.

Characteristics of mucin hypersecretion in different inflammatory patterns based on endotypes of chronic rhinosinusitis

BACKGROUND

Chronic rhinosinusitis (CRS) is usually accompanied by mucin hypersecretion that can lead to mucus accumulation and impair nasal mucociliary clearance, thus exacerbating airway inflammation. Abnormal mucin hypersecretion is regulated by different T helper (Th) cytokines, which are associated with different endotype-driven inflammatory responses. Therefore, it is of great significance to understand how these factors regulate mucin hypersecretion to provide precise treatment strategies for different endotypes of CRS. BODY: Thus far, the most common endotypes of CRS are classified as type 1, type 2, or type 3 immune responses based on innate and adaptive cell-mediated effector immunity, and the representative Th cytokines in these immune responses, such as IFN-γ, TNF-α, IL-4, IL-5, IL-13, IL-10, IL-17, and IL-22, play an important regulatory role in mucin secretion. We reviewed all the related literature in the PubMed database to determine the expression of these Th cytokines in CRS and the role they play in the regulation of mucin secretion.

CONCLUSION

We believe that the main Th cytokines involved in specific endotypes of CRS play a key role in regulating abnormal mucin secretion, which contributes to better understanding of the pathogenesis of CRS and provides therapeutic targets for airway inflammatory diseases associated with mucin hypersecretion.

Chemerin and IL-17 are potential predictors and Chemerin silencing alleviates inflammatory response and bone remodeling in chronic rhinosinusitis

Chronic rhinosinusitis (CRS) is an inflammatory disease of paranasal sinuses. This study is formulated to explore the roles of pro-inflammatory factors Chemerin and interleukin-17 (IL-17) in CRS. Patients suffering from CRS without/with nasal polyps (CRSsNP/CRSwNP), along with volunteers, were recruited. CRS rabbit models were constructed by Staphylococcus aureus infection and rabbits were injected with lentiviral vectors of short hairpin RNA-targeting Chemerin (shChemerin), followed by micro-computed tomography (CT) scan. Levels of Chemerin and IL-17 were determined, and histopathological lesions were observed in subjects and CRS rabbits. Correlations between Chemerin/IL-17 level and Lund-Mackay/Lund-Kennedy scores of subjects and the predictive value of Chemerin or IL-17 for CRS were analyzed. In CRS patients and rabbits, inflammatory degrees and the level of Chemerin/IL-17 were increased in pathological tissues or plasma, while Chemerin silencing alleviated CRS symptoms of CRS rabbits. Chemerin and IL-17 were mainly located in the immune cells of pathological tissues and presented the positive correlation with Lund-Mackay/Lund-Kennedy score of CRS patients. Also, they showed high predictive value for CRS. Micro-CT scan uncovered that CRS rabbits had increased bone remodeling, which was alleviated by Chemerin silencing. Collectively, Chemerin and IL-17 are potential predictors and Chemerin silencing alleviates inflammatory response and bone remodeling in chronic rhinosinusitis.

[The correlation between FCER2 gene polymorphism and the efficacy of inhaled corticosteroids in patients with chronic rhinosinusitis]

Objective:To investigate the correlation between FCER2（2206A>G） gene polymorphism and the efficacy of inhaled corticosteroids（ICS） in patients with chronic rhinosinusitis（CRS）. Methods:A total of 208 CRS patients were routinely treated with functional endonasal sinus surgery and postoperative ICS. DNA extraction, PCR amplification and gene sequencing were performed to observe the FCER2（2206A>G） gene polymorphism and calculate the allele frequency. The visual analog scale（VAS） score, Lund-Kennedy score, and computed tomography（CT） Lund-Mackay score were determined 6 months after surgery among patients with different genotypes. Moreover, the polymorphism frequency was compared among different subgroups（chronic rhinosinusitis with nasal polyps versus chronic rhinosinusitis without nasal polyps, eosinophilic chronic rhinosinusitis versus non-eosinophilic chronic rhinosinusitis）. Results:There were FCER2（2206A>G） gene polymorphism in patients with CRS, and the phenotypes included 3 genotypes, AA, AG and GG, with distribution frequencies of 68（32.7%）, 116（55.8%） and 24（11.5%） cases, respectively. No significant differences were found in age, VAS score, nasal endoscopic Lund-Kennedy score and CT imaging Lund-Mackay score among patients with CRS of each genotype before surgery. In patients with the AA genotype, the changes in VAS score（5.74±1.10）, Lund Kennedy score（5.92 ± 1.14）, and CT imaging Lund-Mackay score（13.26±4.26） were significantly higher than in patients with the AG（4.37±0.86, 5.37±1.24, 10.82±3.77） and GG（4.26±0.80, 5.18±1.56, 10.10±3.53） genotype（P<0.05）. However, there were no marked difference between patients with the AG genotype and those with the GG genotype（P>0.05）. Compared with patients with non-eosinophilic sinusitis, Among them, the differences between the GG genotype and AG /AA genes were more significant in eosinophilic sinusitis compared to non-eosinophilic sinusitis（P<0.01）. Conclusion:The FCER2（2206A>G） gene in patients with CRS has genetic polymorphism and is associated with the recovery of CRS patients after surgery, individual corticosteroid sensitivity, and subgroup variability.

Association of cytokine profile with prior treatment failure and revision surgery in chronic rhinosinusitis

BACKGROUND

Inflammatory patterns in chronic rhinosinusitis (CRS) may predict disease severity, need for multiple sinus surgeries, and treatment response. This study analyzes nasal mucus inflammatory cytokine patterns in patients with (CRSwNP) and without (CRSsNP) nasal polyposis and their association with revision sinus surgery.

METHODS

A total of 319 CRS patients who underwent sinus surgery were included. Cytokines were quantified in intraoperative mucus specimens using a multiplex flow cytometric bead assay. Cytokine expression patterns in patients with 0, 1, and ≥2 previous surgeries were analyzed using Kruskal-Wallis and principal component (PC) regression analyses.

RESULTS

There were 122 (38%) patients with CRSsNP and 197 (62%) with CRSwNP. On univariate analysis, interleukin (IL)-1β, IL-6, IL-8, and IL-21 were associated with increasing number of sinus surgeries in CRSsNP, as were IL-2, IL-4, IL-5, IL-6, IL-9, IL-17A, and tumor necrosis factor (TNF)-α in CRSwNP. PC analysis with continuous Poisson regression in CRSwNP demonstrated that high IL-5 and IL-13 and low IL-1β, IL-12, and IL-21 were associated with more prior surgeries. In CRSsNP low IL-13 and high IL-5 and regulated-on-activation, normal T-cell-expressed and secreted (RANTES) were associated with more prior surgeries. Age remained a significant covariate in the full regression model for CRSsNP, but was nonsignificant in CRSwNP.

CONCLUSION

In CRSwNP, elevated IL-5 and IL-13 levels were higher at time of surgery in patients with more prior surgeries. Type 2 cytokines in CRSsNP demonstrated mixed associations with revision surgery. For both phenotypes, IL-10, IL-12, and IL-21 were consistently lower as number of prior surgeries increased, suggesting that treatment-resistant disease may be modulated by impairment in these signaling pathways.

Psoriasis and Systemic Inflammatory Disorders

Psoriasis is a representative inflammatory skin disease occupied by large surface involvement. As inflammatory cells and cytokines can systemically circulate in various organs, it has been speculated that psoriatic skin inflammation influences the systemic dysfunction of various organs. Recent updates of clinical studies and experimental studies showed the important interaction of psoriasis to systemic inflammatory diseases. Furthermore, the importance of systemic therapy in severe psoriasis is also highlighted to prevent the development of systemic inflammatory diseases. In this review, we introduced representative systemic inflammatory diseases associated with psoriasis and the detailed molecular mechanisms.

[Etiopathophysiological mechanism of systemic and local allergic sensitization in the development of chronic rhinitis and chronic rhinosinusitis]

The persistence, development and exacerbation of chronic rhinitis and chronic rhinosinusitis all involve sensitization to respiratory allergens. The allergic response in question is the IgE-mediated mechanism of rhinitis, which often leads to a complex of etiopathophysiological malfunctions in various organs and systems. For clinical classification and further management of patients, it is important not to miss the detection of both systemic allergic sensitization to aeroallergens (which is achieved by conducting skin prick test or detecting the allergen-specific immunoglobulin E in the blood) and local sensitization (which can be confirmed by conducting nasal provocation test or detecting the nasal-specific immunoglobulin E in nasal mucosa). Before a full examination is conducted and both systemic and local sensitization are ruled out, the diagnosis of non-allergic rhinitis and the management of a patient with non-allergic nasal inflammation may be premature.

Stromal cells and B cells orchestrate ectopic lymphoid tissue formation in nasal polyps

BACKGROUND

Although the importance of ectopic lymphoid tissues (eLTs) in the pathophysiology of nasal polyps (NPs) is increasingly appreciated, the mechanisms underlying their formation remain unclear.

OBJECTIVE

To study the role of interleukin (IL)-17A, C-X-C motif chemokine ligand 13 (CXCL13) and lymphotoxin (LT) in eLT formation in NPs.

METHODS

The expression levels of CXCL13 and LT and their receptors, in addition to the phenotypes of stromal cells in NPs, were studied by flow cytometry, immunostaining, and real-time reverse transcription-polymerase chain reaction (RT-PCR). Purified nasal stromal cells and B cells were cultured, and a murine model of nasal type 17 inflammation was established by intranasal curdlan challenge for the mechanistic study.

RESULTS

The excessive CXCL13 production in NPs correlated with enhanced IL-17A expression. Stromal cells, with CD31^- Pdpn⁺ fibroblastic reticular cell (FRC) expansion, were the major source of CXCL13 in NPs without eLTs. IL-17A induced FRC expansion and CXCL13 production in nasal stromal cells. In contrast, B cells were the main source of CXCL13 and LTα₁ β₂ in NPs with eLTs. CXCL13 upregulated LTα₁ β₂ expression on B cells, which in turn promoted CXCL13 production in nasal B cells and stromal cells. LTα₁ β₂ induced expansion of FRCs and CD31⁺ Pdpn⁺ lymphoid endothelial cells, which were the predominant stromal cell types in NPs with eLTs. IL-17A knockout and CXCL13 and LTβR blockage diminished nasal eLT formation in the murine model.

CONCLUSION

We identified an important role of IL-17A-induced stromal cell remodeling in the initiation and crosstalk between B and stromal cells via CXCL13 and LTα₁ β₂ in the enlargement of eLTs in NPs.

Elevated mucus interleukin-17A levels are associated with increased prior sinus surgery for chronic rhinosinusitis

BACKGROUND

Recent advances in molecular biology have enabled the identification of potential inflammatory endotypes of chronic rhinosinusitis (CRS), with prior work suggesting differential short-term surgical outcome trajectories based on cytokine signatures. However, there is a paucity of data assessing long-term treatment failure and need for revision surgery based on inflammatory biomarkers.

METHODS

Retrospective analysis of prospectively collected cross-sectional data from 231 patients electing surgical therapy for CRS. Intraoperative mucus specimens were quantitatively sampled for inflammatory cytokines using a multiplex flow cytometric bead assay. Univariate Spearman correlations between cytokine levels and prior number of surgeries were assessed. A stepwise adjusted multivariate Poisson regression analysis was used to model patient-reported prior sinus surgery counts as a function of cytokine levels.

RESULTS

Several cytokines (interleukin [IL]-1β, IL-4, IL-5, IL-6, IL-8, IL-10, IL-13, IL-17A, tumor necrosis factor α [TNF-α], interferon γ [IFN-γ], and eotaxin) demonstrated significant positive correlations with number of prior surgeries. However, only higher IL-17A levels were independently associated with a higher number of prior sinus surgeries (β = 0.345, p = 0.0003) after adjusting for the significant covariates of age (β = 0.018, p = 0.0036), Lund-Mackay score (β = -0.046, p = 0.02), history of aspirin-exacerbated respiratory disease (β = 1.01, p < 0.0001) and allergic fungal rhinosinusitis (β = 1.08, p < 0.0001). Higher levels of regulated on activation, normal T-cell expressed and secreted (RANTES) were conversely associated with a lower number of prior surgeries (β = -0.17, p = 0.048).

CONCLUSION

An IL-17A-predominant cytokine profile is linked to an increased number of prior sinus surgeries. Thus, type 3 inflammatory markers may indicate a particularly difficult-to-treat, recalcitrant CRS endotype.

Co-infection of Malassezia sympodialis With Bacterial Pathobionts Pseudomonas aeruginosa or Staphylococcus aureus Leads to Distinct Sinonasal Inflammatory Responses in a Murine Acute Sinusitis Model

Host-associated bacteria and fungi, comprising the microbiota, are critical to host health. In the airways, the composition and diversity of the mucosal microbiota of patients are associated with airway health status. However, the relationship between airway microbiota and respiratory inflammation is not well-understood. Chronic rhinosinusitis (CRS) is a complex disease that affects up to 14% of the US population. Previous studies have shown decreased microbial diversity in CRS patients and enrichment of either Staphylococcus aureus or Pseudomonas aeruginosa. Although bacterial community composition is variable across CRS patients, Malassezia is a dominant fungal genus in the upper airways of the majority of healthy and CRS subjects. We hypothesize that distinct bacterial-fungal interactions differentially influence host mucosal immune response. Thus, we investigated in vitro and in vivo interactions between Malassezia sympodialis, P. aeruginosa, and S. aureus. The in vitro interactions were evaluated using the modified Kirby-Bauer Assay, Crystal Violet assay for biofilm, and FISH. A pilot murine model of acute sinusitis was used to investigate relationships with the host immune response. S. aureus and P. aeruginosa were intranasally instilled in the presence or absence of M. sympodialis (n = 66 total mice; 3–5/group). Changes in the microbiota were determined using 16S rRNA gene sequencing and host immune response was measured using quantitative real-time PCR (qRT-PCR). In vitro, only late stage planktonic P. aeruginosa and its biofilms inhibited M. sympodialis. Co-infection of mice with M. sympodialis and P. aeruginosa or S. aureus differently influenced the immune response. In co-infected mice, we demonstrate different expression of fungal sensing (Dectin-1), allergic responses (IL-5, and IL-13) and inflammation (IL-10, and IL-17) in murine sinus depending on the bacterial species that co-infected with M. sympodialis (p < 0.05). The pilot results suggest that species-specific interactions in airway-associated microbiota may be implicated driving immune responses. The understanding of the role of bacterial-fungal interactions in CRS will contribute to development of novel therapies toward manipulation of the airway microbiota.

Increased TSLP, IL-33, IL-25, IL-19, IL 21 and amphiregulin (AREG) levels in chronic rhinosinusitis with nasal polyp

OBJECTIVE

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a chronic inflammatory disease. The surrogate indicating biomarkers in patients with CRSwNP need further evaluation. The aim of this study was to investigate the association of thymic stromal lymphopoietin (TSLP) and amphiregulin (AREG) cytokines in patients with CRSwNP.

METHODS

Sinonasal tissue samples were collected from 33 patients with CRSwNP and 29 controls. Levels of AREG, IL-19, IL-21, IL-25, IL-33 and TSLP in nasal polyp and control sinonasal tissues were determined following the enzyme-linked immunosorbent assay method.

RESULTS

We found that AREG, IL-19, IL-21, IL-25, IL-33 and TSLP levels were significantly higher in the CRSwNP group compared to the control group (p < 0.000; p < 0.000; p < 0.000; p < 0.000; p < 0.003; p < 0.021, respectively).

CONCLUSIONS

Our findings indicated that AREG, IL-19, IL-21, IL-25, IL-33 and TSLP were significantly increased in tissue samples of CRSwNP patients and may be considered as molecular indicators and targets for therapeutic developments for patients with CRSwNP.

Chronic Rhinosinusitis: Does Allergy Play a Role?

A few chronic rhinosinusitis (CRS) variants have demonstrated a strong association with environmental allergy, including allergic fungal rhinosinusitis (AFRS) and central compartment atopic disease (CCAD). However, the overall relationship between CRS and allergy remains poorly defined. The goal of this review is to evaluate the relationship between CRS and allergy with a focus on specific CRS variants.

Chronic rhinosinusitis: pathogenesis, therapy options, and more

INTRODUCTION

When rhinosinusitis - the inflammation of the nasal cavity and paranasal sinuses - persists for over 12 weeks, it is termed 'chronic rhinosinusitis' (CRS). Both innate and adaptive immunity contribute to the heterogeneous inflammatory pathogenesis of CRS, which is driven by genetic and environmental factors and the microbiome. CRS is classified by the presence of polyps. Molecular mechanisms in CRS with nasal polyps are similar to those in atopic diseases.

AREAS COVERED

This review focuses on the immune pathogenesis of CRS, differences between the two CRS subtypes, and latest treatments that may aid in the provision of personalized medicine.

EXPERT OPINION

Basic research in the last decade has helped significantly in enhancing our knowledge of the pathophysiologic processes of CRS, due to which there is now a better understanding of the associated natural history, physiopathology, novel treatments, and prevention strategies. Treatment success depends on the clarification of the underlying pathogenesis and disease-contributing factors. The exploration of disease endotypes and introduction of novel agents are important advancements. Prior studies performed without disease-endotyping resulted in the inefficiency of certain drugs and insignificant results. The identification of biomarkers, development of personalized approaches, and utilization of disease algorithms are required for CRS therapy success.