Increased presence of dendritic cells and dendritic cell chemokines in the sinus mucosa of chronic rhinosinusitis with nasal polyps and allergic fungal rhinosinusitis

M2 macrophage-related gene signature in chronic rhinosinusitis with nasal polyps

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a common sinonasal inflammatory disorder with high heterogeneity. Increasing evidence have indicated that the infiltration of macrophages especially M2 macrophages play pivotal roles in the pathogenesis of CRSwNP, but the underlying mechanisms remain undetermined. This study sought to identify potential biomarkers related to M2 macrophages in CRSwNP.

METHODS

The expression datasets of GSE136825 and GSE179265 were download from Gene Expression Omnibus (GEO) database and merged. Then, CIBERSORT and weighted gene co-expression network analysis (WGCNA) algorithms were applied to identify M2 macrophage-related gene modules. Thereafter, differentially expressed genes (DEGs) related to M2 macrophages were selected to perform functional enrichment analyses. A protein-protein interaction (PPI) network was built to identify hub genes and quantitative real-time reverse transcriptions PCR was used to verify the bioinformatics results.

RESULTS

A total of 92 DEGs associated with M2 macrophages were identified for further analysis. The results of Gene ontology (GO) and Kyoto Encyclopedia of genes and genomes (KEGG) analyses illustrated that M2 macrophage-associated DEGs primarily enriched in immune responses and extracellular matrix structure. PPI network analysis identified 18 hub genes related to M2 macrophages that might be pivotal in the pathogenesis of CRSwNP. After verification, AIF1, C1QA, C1QB, C3AR1, CCR1, CD163, CD4, CD53, CD86, CSF1R, CYBB, FCER1G, FCGR3A, IL10RA, ITGB2, LAPTM5, PLEK, TYROBP were identified as potential M2 macrophage-related biomarkers for CRSwNP.

CONCLUSION

These findings yield new insights into the hub genes and mechanisms related to M2 macrophages in the pathogenesis of CRSwNP. Further studies of these hub genes would help better understand the disease progression and identify potential treatment targets.

Different Roles of Dendritic Cells for Chronic Rhinosinusitis Treatment According to Phenotype

Dendritic cells (DCs) are antigen-presenting cells derived from the bone marrow that play an important role in the association between the innate and adaptive immune responses. The onset and development of chronic rhinosinusitis (CRS) involve a serious imbalance in immune regulation and mechanical dysfunction caused by an abnormal remodeling process. Recent studies have shown that an increase in DCs in CRS and their function of shaping the nasal mucosal immune response may play an important role in the pathogenesis of CRS. In this review, we discuss DC subsets in mice and humans, as well as the function of DCs in the nasal sinus mucosa. In addition, the mechanism by which DCs can be used as targets for therapeutic intervention for CRS and potential future research directions are also discussed.

Immunolocalization of CD1a expressing dendritic cells in sinonasal polyposis

Sinonasal polyps are benign projections of edematous nasal mucosa lined by respiratory epithelium. Langerhans cells (LCs) belonging to the dendritic cell family located in respiratory epithelium are involved in antigen presentation and maintenance of local immunological homeostasis. This study aims to elucidate the morphology and distribution of CD1a positive LCs in normal nasal mucosa and compare the same with polypoid nasal mucosa by immunohistochemistry. Normal nasal mucosa (n = 20) was obtained from patients who underwent septoplasty for deviated nasal septum. Polypoid nasal mucosa (n = 22) was obtained from patients with chronic rhinosinusitis (CRS) or allergic fungal rhinosinusitis who underwent excision of nasal polyps. The tissues obtained were processed for immunohistochemistry and stained with CD1a-EP80 Rabbit monoclonal antibody. In the tissues studied, CD1a positive LCs were observed in both the epithelium and lamina propria. Different morphological subtypes of LCs were noted in the epithelium. The cells were distributed adjacent to walls of subepithelial capillaries and cysts. The median number of CD1a positive LCs was significantly higher in polypoid category (13.5 per mm²) as compared with normal nasal mucosa (2.5per mm²) (p = .001). Presence of CD1a positive LCs in polypoid nasal mucosa hints at a critical immunological role in the etiopathogenesis of nasal polyps.

miRNA-205-5p can be related to T2-polarity in Chronic Rhinosinusitis with Nasal Polyps

BACKGROUND

microRNAs (miRNAs) are directly associated with inflammatory response, but their direct role in CRSwNP (chronic rhinosinusitis with nasal polyps) remains evasive. This study aimed to compare the expression of several miRNAs in tissue samples obtained from patients with CRSwNP and controls and to evaluate if miRNAs correlate to a specific inflammatory pattern (T1, T2, T17, and Treg) or intensity of symptoms in CRSwNP.

METHODS

nasal polyps (from patients with CRSwNP - n=36) and middle turbinate mucosa (from control patients - n=41) were collected. Microarray determined human mature miRNA expression, and the results obtained were validated by qPCR. miRNAs that were differentially expressed were then correlated to cytokine proteins (by Luminex), tissue eosinophilia, and SNOT-22.

RESULTS

After microarray and qPCR analyses, six microRNAs were up-regulated in CRSwNP samples when compared with controls: miR-205-5p, miR-221-3p, miR-222-3p, miR-378a-3p, miR-449a and miR-449b-5p. All these miRNAs are directly implicated with cell cycle regulation and apoptosis, and to a minor extent, with inflammation. Importantly, miR-205-5p showed a significantly positive correlation with IL-5 concentration and eosinophil count at the tissue and with the worst SNOT-22 score.

CONCLUSIONS

miRNA 205-5p was increased in CRSwNP compared to controls, and it was especially expressed in CRSwNP patients with higher T2 inflammation (measured by both IL-5 levels and local eosinophilia) and worst clinical presentation. This miRNA may be an interesting target to be explored in patients with CRSwNP.

International consensus statement on allergy and rhinology: rhinosinusitis 2021

I.

EXECUTIVE SUMMARY

BACKGROUND: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICAR-RS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICAR-RS-2021 as well as updates to the original 140 topics. This executive summary consolidates the evidence-based findings of the document.

METHODS

ICAR-RS presents over 180 topics in the forms of evidence-based reviews with recommendations (EBRRs), evidence-based reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary.

RESULTS

ICAR-RS-2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidence-based management algorithm is provided.

CONCLUSION

This ICAR-RS-2021 executive summary provides a compilation of the evidence-based recommendations for medical and surgical treatment of the most common forms of RS.

Current Concepts in the Management of Allergic Fungal Rhinosinusitis

Allergic fungal rhinosinusitis (AFRS) represents a subtype of chronic rhinosinusitis with nasal polyposis that exhibits a unique, often striking clinical presentation. Since its initial description more than a quarter century ago, a more sophisticated understanding of the pathophysiology of AFRS has been achieved and significant advancements in improving clinical outcomes made. This review focuses on the latest developments involving the pathophysiology and clinical management of this fascinating disease.

Respiratory tract mucous membrane microecology and asthma

According to the world health organization, the increasing incidence of asthma is placing a heavy burden on the social economy. Its high rate of disability and mortality has become a serious social and public health problem. Asthma is a heterogeneous disease in which genetic polymorphism interacts with environmental factors. Because the pathogenesis of asthma is not completely clear, there is no specific treatment. In 2010, 16S rRNA gene sequencing showed that lungs have many different microbial communities in both healthy and sick states. These microbial communities and respiratory mucosa constitute the respiratory mucosal microecology. When the respiratory mucosal microecology changes, it can play a key role in the occurrence and development of asthma and other respiratory diseases by regulating the immune mechanism. This paper reviews the latest research results in this field, and tries to explore the effects of changes in respiratory mucosal microecology on the pathogenesis of asthma, so as to provide new methods for early diagnosis, treatment and prevention of asthma.

Current understanding of allergic fungal rhinosinusitis

Studying the pathophysiology of allergic fungal rhinosinusitis (AFRS) has proved challenging. While this clinical entity is easily distinguishable based on the clinical criteria set forth by Bent and Kuhn twenty-five years ago, studies examining type 2 inflammatory profiles in AFRS can make it seem more alike other CRS subtypes than it is different. Still, evolving research seems to clearly delineate this subtype from others in CRS. This review will critically evaluate the evolution of research examining the pathophysiology of AFRS and will conclude with a summary of the special considerations in the management of this fascinating disease.

C3a receptor antagonism as a novel therapeutic target for chronic rhinosinusitis

Chronic rhinosinusitis with nasal polyps (CRSwNP) is an inflammatory disease with an unknown etiology. Recent studies have implicated the complement system as a potential modulator of disease immunopathology. We performed proteomic pathway enrichment analysis of differentially increased proteins, and found an enrichment of complement cascade pathways in the nasal mucus of individuals with CRSwNP as compared to control subjects. Sinonasal mucus levels of complement 3 (C3) correlated with worse subjective disease severity, whereas no significant difference in systemic C3 levels could be determined in plasma samples. Given that human sinonasal epithelial cells were the predominate sinonasal source of C3 and complement anaphylatoxin 3a (C3a) staining, we focused on their role in in vitro studies. Baseline intracellular C3 levels were higher in CRSwNP cells, and following exposure to Aspergillus fumigatus (Af) extract, they released significantly more C3 and C3a. Inhibition of complement 3a receptor (C3aR) signaling led to a decrease in Af-induced C3 and C3a release, both in vitro and in vivo. Finally, we found in vivo that C3aR deficiency or inhibition significantly reduced inflammation and CRS development in a mouse model of Af-induced CRS. These findings demonstrate that local sinonasal complement activation correlates with subjective disease severity, and that local C3aR antagonism significantly ameliorates Af-induced CRS in a rodent model.

MiR-150-5p regulates EGR2 to promote the development of chronic rhinosinusitis via the DC-Th axis

BACKGROUND AND AIMS

Accumulating studies indicate that miR-150-5p might play a significant role in dendritic cells (DCs) of peripheral blood in chronic rhinosinusitis (CRS) patients. We sought to investigate the effects and mechanism of miR-150-5p, which regulates early growth response 2 (EGR2) to promote the development of CRS via the DC-Th axis.

METHODS

The upregulated expression of miR-150-5p in DCs of CRS was assayed by real-time quantitative polymerase chain reaction (qRT-PCR), and IL-17 cytokines in the supernatants of DC-naïve T cells co-cultures were analysed by enzyme-linked immunosorbent assay (ELISA). Flow cytometry was used to evaluate T cell proliferations. EGR2 was also identified as a direct target of miR-150-5p by establishing a miRNA-mRNA network, and this target was validated with a Dual-Luciferase® Reporter Assay System and Western blot.

RESULTS

MiR-150-5p was up-regulated in DCs in peripheral blood from CRS patients, and this expression was down-regulated by EGR2 expression via the DC-Th axis. Up-regulated miR-150-5p Regulates DCs, and DCs Promote Naïve T Cells Proliferation. MiR-150-5p Further Regulates EGR2 and Inhibits DCs, Which Makes the DC-Th Axis Abnormal in the Peripheral Blood of Patients with CRS.

CONCLUSION

MiR-150-5p and its identified target, EGR2, are involved in the development of CRS. DCs can promote T cell proliferations of peripheral blood in CRS.

Impact of tobacco smoke on upper airway dendritic cell accumulation and regulation by sinonasal epithelial cells

BACKGROUND

In these studies we examined the impact of environmental tobacco smoke (ETS) and active smoking on sinonasal dendritic cell (DC) subsets in controls or patients with chronic rhinosinusitis with nasal polyps (CRSwNP). In subsequent in-vitro investigations, we examined the influence of cigarette smoke extract (CSE) on human sinonasal epithelial cells' (HSNECs) ability to regulate DC functions.

METHODS

Sinonasal tissue, blood, and hair were collected from patients undergoing sinus surgery. Smoking status and ETS exposure were determined by hair nicotine. DC subsets were examined by flow cytometric analysis. Monocyte-derived dendritic cells (moDCs) were treated with conditioned medium from non-smoked-exposed HSNECs (NS-HSNECs) or cigarette-smoke-extract-exposed HSNECs (CSE-HSNECs) to assess the impact of CSE exposure on HSNEC regulation of moDC functions.

RESULTS

Control subjects who were active smokers displayed increased sinonasal moDC and myeloid dendritic 1 (mDC1) cells and reduced mDC2 cells, whereas, in CRSwNP patients, only moDC and mDC2 cells were altered. ETS was found to increase only moDCs in the CRSwNP patients. In vitro, CSE stimulated HSNEC secretion of the moDC regulatory products chemokine (C-C motif) ligand 20, prostaglandin E2 , and granulocyte-macrophage colony-stimulating factor. CSE exposure also promoted HSNECs to stimulate monocyte and moDC migration. moDCs treated with CSE-HSNEC media stimulated an increase in antigen uptake and expression of CD80 and CD86. Last, CSE-HSNEC-treated moDCs secreted increased levels of interleukin-10, interferon-γ, and thymic stromal lymphopoietin.

CONCLUSION

Active smoking, and to a lesser degree ETS, alters the sinonasal composition of DCs. A potential mechanism to account for this is that cigarette smoke stimulates HSNECs to induce moDC migration, maturation, and activation.

Selective expansion of human regulatory T cells in nasal polyps, and not adjacent tissue microenvironments, in individual patients exposed to steroids

Severe forms of chronic rhinosinusitis (CRS), a common upper airway inflammatory disorder, are associated with nasal polyps (NPs). NP disease is ameliorated by glucocorticoid (GC) treatment, whose cellular effects are poorly understood. We therefore assessed the influence of GC therapy on NPs in CRS patients, focusing on regulatory T (T_reg) cells. T_reg cell populations were analyzed by flow cytometry in NPs and control tissues from GC-treated CRS patients and controls. After GC exposure, selective expansion of T_reg cells was seen within NPs, and not blood or adjacent ethmoid tissues. To confirm direct GC effects, NPs from the same patients were biopsied prior to, and following, 1week of oral GC exposure. Direct expansion of Tregs into the same NP bed was detected in 4/4 CRS patients following GC exposure. T_reg cell spikes into NPs were secondary to cellular recruitment given limited Ki67 expression within these regulatory cells. Chemokine gene expression profiling identified several chemokines, notably CCL4, induced within NPs upon GC treatment. Neutralization of chemokine receptor/ligand interactions using CCR4 small molecule antagonists reduced T_reg migration towards GC-treated NPs in an ex vivo migration assay. Our findings suggest that the common use of GCs in the treatment of NP disease leads to recruitment of T_reg cells from peripheral sites into NP tissues, which may be critical to the anti-inflammatory effect of GCs. Mechanistically T_reg expansion appears to be conferred, in part, by chemokine receptor/ligand interactions induced following corticosteroid therapy.

Allergic Aspergillus Rhinosinusitis

Allergic fungal rhinosinusitis (AFRS) is a unique variety of chronic polypoid rhinosinusitis usually in atopic individuals, characterized by presence of eosinophilic mucin and fungal hyphae in paranasal sinuses without invasion into surrounding mucosa. It has emerged as an important disease involving a large population across the world with geographic variation in incidence and epidemiology. The disease is surrounded by controversies regarding its definition and etiopathogenesis. A working group on "Fungal Sinusitis" under the International Society for Human and Animal Mycology (ISHAM) addressed some of those issues, but many questions remain unanswered. The descriptions of "eosinophilic fungal rhinosinusitis" (EFRS), "eosinophilic mucin rhinosinusitis" (EMRS) and mucosal invasion by hyphae in few patients have increased the problem to delineate the disease. Various hypotheses exist for etiopathogenesis of AFRS with considerable overlap, though recent extensive studies have made certain in depth understanding. The diagnosis of AFRS is a multi-disciplinary approach including the imaging, histopathology, mycology and immunological investigations. Though there is no uniform management protocol for AFRS, surgical clearing of the sinuses with steroid therapy are commonly practiced. The role of antifungal agents, leukotriene antagonists and immunomodulators is still questionable. The present review covers the controversies, recent advances in pathogenesis, diagnosis, and management of AFRS.

Dendritic cells in inflammatory sinonasal diseases

Dendritic cells (DCs) are critical in linking the innate and adaptive immune responses, which have been implicated in the pathogenesis of many immune and inflammatory diseases as well as the development of tumours. The role of DCs in the pathophysiology of lung diseases has been widely studied. However, the phenotype, subset and function of DCs in upper airways under physiological or pathological conditions remain largely undefined. Allergic rhinitis (AR) and chronic rhinosinusitis (CRS) are two important upper airway diseases with a high worldwide prevalence. Aberrant innate and adaptive immune responses have been considered to play an important role in the pathogenesis of AR and CRS. To this end, understanding the function of DCs in shaping the immune responses in sinonasal mucosa is critical in exploring the pathogenic mechanisms underlying AR and CRS as well as in developing novel therapeutic strategies. This review summarizes the phenotype, subset, function and regulation of DCs in sinonasal mucosa, particularly in the setting of AR and CRS. Furthermore, this review discusses the perspectives for future research and potential clinical utility focusing on DC pathways in the context of AR and CRS.

Innate immunity and chronic rhinosinusitis: What we have learned from animal models

OBJECTIVE

Chronic rhinosinusitis (CRS) is a heterogeneous and multifactorial disease characterized by dysregulated inflammation. Abnormalities in innate immune function including sinonasal epithelial cell barrier function, mucociliary clearance, response to pathogen-associated molecular patterns (PAMPs) via pattern recognition receptors (PRRs), and the contribution of innate immune cells will be highlighted in this review.

DATA SOURCES

PubMed literature review.

REVIEW METHODS

A review of the literature was conducted to determine what we have learned from animal models in relation to innate immunity and chronic rhinosinusitis.

RESULTS

Dysregulation of innate immune mechanisms including sinonasal barrier function, mucociliary clearance, PAMPs, and innate immune cells such as eosinophils, mast cells, and innate lymphoid cells may contribute to CRS pathogenesis. Sinonasal inflammation has been studied using mouse, rat, rabbit, pig, and sheep explant or in vivo models. Study using these models has allowed for analysis of experimental therapeutics and furthered our understanding of the aforementioned aspects of the innate immune mechanism as it relates to sinonasal inflammation. These include augmenting mucociliary clearance through activation of the cystic fibrosis transmembrane conductance regulator (CFTR) and study of drug toxicity on ciliary beat frequency. Knockout models of Toll-like receptors (TLR) have demonstrated the critical role these PRRs play in allergic inflammation as loss of TLR2 and TLR4 leads to decreased lower airway inflammation. Mast cell deficient mice are less susceptible to ovalbumin-induced sinonasal inflammation.

CONCLUSION

Animal models have shed light as to the potential contribution of dysregulated innate immunity in chronic sinonasal inflammation.

Cytokine patterns in nasal secretion of non-atopic patients distinguish between chronic rhinosinusitis with or without nasal polys

BACKGROUND

Being one of the most common nasal diseases, chronic rhinosinusitis (CRS) is subdivided into CRS with nasal polyps (NP) and CRS without nasal polyps (CRSsNP). CRSsNP presents itself with a TH1 milieu and neutrophil infiltration, while NP is characterised by a mixed TH1/TH2 profile and an influx of predominantly eosinophils, plasma cells and mast cells. For the purpose of discovering disease-specific cytokine profiles, the present study compares levels of mediators and cytokines in nasal secretions between CRSsNP, NP, and healthy controls.

METHODS

The study included 45 participants suffering from NP, 48 suffering from CRSsNP and 48 healthy controls. Allergic rhinitis constituted an exclusion criterion. Nasal secretions, sampled using the cotton wool method, were analysed for IL-4, IL-5, IL-10, IL-12, IL-13, IL-17, IL-8, GM-CSF, G-CSF, IFN-γ, MCP-1, MIP-1α, MIP-1β, eotaxin, and RANTES, and for ECP and tryptase, using Bio-Plex Cytokine assay or ELISA, respectively.

RESULTS

Elevated levels of IL-5, IL-17, G-CSF, MCP-1, MIP-1α, MIP-1β, ECP, and tryptase, as well as decreased levels of IL-10, IL-12, IL-13, and IFN-γ were detected in NP. CRSsNP presented increased levels of RANTES and MIP-1β while IL-13 was decreased. No differences between the three groups were found for IL-4, IL-8, GM-CSF, and eotaxin.

CONCLUSIONS

The present work suggests a disequilibrium of TH1 and TH2, together with a down-regulation of regulatory T lymphocytes and up-regulated TH17 in NP. Moreover, elevated levels of diverse mediators represent the activation of various inflammatory cells in this disease entity. The inflammation in CRSsNP, however, is only weakly depicted in nasal secretions. Therefore, cytokines in nasal secretions may provide helpful information for differential diagnosis.

Reduced sinonasal levels of 1α-hydroxylase are associated with worse quality of life in chronic rhinosinusitis with nasal polyps

BACKGROUND

Patients with chronic rhinosinusitis with nasal polyps (CRSwNP) have deficiencies in circulating and sinonasal levels of the inactive form of vitamin D3, 25-hydroxycholecalciferol (25VD3). Moreover, CRSwNP patients have reduced epithelial cell-specific expression of 1α-hydroxylase; the enzyme responsible for the conversion of 25VD3 to its metabolically active form, 1α,25-dihydroxyvitamin D3 (1,25VD3). The objective of this work was to determine the impact of sinonasal 1α-hydroxylase levels combined from all cellular sources on subjective disease severity and to identify variables influencing its expression.

METHODS

Blood and sinus tissue explants were collected at the time of surgery from control, chronic rhinosinusitis without nasal polyps (CRSsNP), CRSwNP, and allergic fungal rhinosinusitis (AFRS) patients. 1α-Hydroxylase was measured by immunostaining with flow cytometric analysis. Subjective disease severity was measured by the 22-item Sino-Nasal Outcomes Test (SNOT-22). 1,25VD3 and 25VD3 were measured by enzyme-linked immunosorbent assay (ELISA).

RESULTS

Patients with CRSwNP or AFRS have reduced 1α-hydroxylase and 1,25VD3 compared to controls or CRSsNP. Circulating 1,25VD3 levels were the same among all groups. No differences in sinonasal 1α-hydroxylase or 1,25VD3 were found between CRSwNP and AFRS. Gender, age, race, atopy, and systemic 25VD3 had no impact on sinonasal 1α-hydroxylase levels in any group. However, CRSwNP patients with asthma had higher 1α-hydroxylase than those without asthma. Total 1α-hydroxylase levels inversely correlated with SNOT-22 in CRSwNP, but not CRSsNP.

CONCLUSION

Patients with CRSwNP and AFRS both have reduced sinonasal 1α-hydroxylase and 1,25VD3 compared to controls or CRSsNP. Reductions in intracellular 1α-hydroxylase combined from all sinonasal cell types were associated with more severe subjective disease severity in CRSwNP.

Vitamin D for the treatment of respiratory diseases: is it the end or just the beginning?

A large number of human, animal and in vitro studies have suggested that vitamin D3 (VD3) plays a critical role in inflammatory airway diseases such as asthma, chronic rhinosinusitis, and allergic rhinitis. VD3 acts upon a broad range of immune cells involved in the pathogenesis of these diseases including T-cells, dendritic cells (DCs), macrophages, and B-cells. In addition, VD3 can also regulate the functions of a number of non-immune cells including epithelial cells, fibroblasts, and smooth muscle cells. Given that VD3 has known effects on the immune system, it seems logical that supplementation with VD3 would prove efficacious in the treatment of these three diseases. While many studies, most of which are observational, have suggested that VD3 deficiency is associated with more severe disease, VD3 supplementation trials in humans have resulted in varied outcomes in terms of efficacy. In this review article we will discuss the role of VD3 in these three commonly associated respiratory diseases. We will explore the literature describing associations of VD3 deficiency with patient outcomes, cells in the respiratory microenvironment susceptible to VD3 regulation, conflicting results of VD3 supplementation trials, and potential gaps in our knowledge that may be limiting the widespread use of VD3 for the treatment of respiratory diseases such asthma, chronic rhinosinusitis and allergic rhinitis. This article is part of a Special Issue entitled '17th Vitamin D Workshop'.

Elevated presence of myeloid dendritic cells in nasal polyps of patients with chronic rhinosinusitis

BACKGROUND

Although chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by Th2 inflammation, the mechanism underlying the onset and amplification of this inflammation has not been fully elucidated. Dendritic cells (DCs) are major antigen-presenting cells, central inducers of adaptive immunity and critical regulators of many inflammatory diseases. However, the presence of DCs in CRS, especially in nasal polyps (NPs), has not been extensively studied.

OBJECTIVE

The objective of this study was to characterize DC subsets in CRS.

METHODS

We used real-time PCR to assess the expression of mRNA for markers of myeloid DCs (mDCs; CD1c), plasmacytoid DCs (pDCs; CD303) and Langerhans cells (LCs; CD1a, CD207) in uncinate tissue (UT) from controls and patients with CRS as well as in NP. We assayed the presence of DCs by immunohistochemistry and flow cytometry.

RESULTS

Compared to UT from control subjects (n = 15) and patients with CRS without NP (CRSsNP) (n = 16) and CRSwNP (n = 17), mRNAs for CD1a and CD1c were significantly elevated in NPs (n = 29). In contrast, CD207 mRNA was not elevated in NPs. Immunohistochemistry showed that CD1c(+) cells but not CD303(+) cells were significantly elevated in NPs compared to control subjects or patients with CRSsNP. Flow cytometric analysis showed that CD1a(+) cells in NPs might be a subset of mDC1s and that CD45(+) CD19(-) CD1c(+) CD11c(+) CD141(-) CD303(-) HLA-DR(+) mDC1s and CD45(+) CD19(-) CD11c(+) CD1c(-) CD141(high) HLA-DR(+) mDC2s were significantly elevated in NPs compared to UT from controls and CRSsNP, but CD45(+) CD11c(-) CD303(+) HLA-DR(+) pDCs were only elevated in NPs compared to control UT.

CONCLUSION AND CLINICAL RELEVANCE

Myeloid DCs are elevated in CRSwNP, especially in NPs. Myeloid DCs thus may indirectly contribute to the inflammation observed in CRSwNP.

Vitamin D3 as a novel regulator of basic fibroblast growth factor in chronic rhinosinusitis with nasal polyposis

BACKGROUND

The immunopathogenesis of chronic rhinosinusitis (CRS) is largely unknown, but it is thought that different inflammatory profiles are responsible for the different CRS subtypes. 25-Hydroxyvitamin-D (25-VD3) has been shown to alter inflammatory mediators in other disease processes and 25-VD3 deficiency is associated with CRS with nasal polyps (CRSwNP), but it is unknown if 25-VD3 levels impact local inflammation in CRS. This study investigated the correlation between plasma 25-VD3 and sinonasal mucus monocyte chemoattractant protein-1 (MCP-1), regulated upon activation normal T cell expressed and secreted (RANTES), and basic fibroblast growth factor (bFGF) levels in patients with CRS.

METHODS

Study subjects undergoing endoscopic sinus surgery (ESS) for CRS were prospectively enrolled from January 2012 to August 2014. Control subjects included patients undergoing ESS for noninflammatory pathology. Blood and sinonasal mucus were collected at the time of ESS. Plasma 25-VD3 was measured by enzyme-linked immunosorbent assay (ELISA) and mucus levels of MCP-1, RANTES, and bFGF by cytometric bead array (CBA).

RESULTS

A total of 57 patients were enrolled and categorized as CRS without nasal polyps (CRSsNP) (n = 31), CRSwNP (n = 14), and controls (n = 12). No significant correlation was found between MCP-1 and 25-VD3. There was a significant negative correlation between 25-VD3 and RANTES (r = -0.612; p = 0.026) and bFGF (r = -0.578; p = 0.039) in CRSwNP patients; however, there was no significant correlation in CRSsNP patients.

CONCLUSION

This data suggests that 25-VD3 may play a role in regulation of RANTES and bFGF expression in CRSwNP. This may occur through regulation of NP fibroblasts or other immune cells. Further investigation is warranted to better elucidate the role of RANTES, bFGF, and 25-VD3 in CRSwNP.

MBP-positive and CD11c-positive cells are associated with different phenotypes of Korean patients with non-asthmatic chronic rhinosinusitis

Background

Asthmatic nasal polyps primarily exhibit eosinophilic infiltration. However, the identities of the immune cells that infiltrate non-asthmatic nasal polyps remain unclear. Thus, we thought to investigate the distribution of innate immune cells and its clinical relevance in non-asthmatic chronic rhinosinusitis (CRS) in Korea.

Methods

Tissues from uncinate process (UP) were obtained from controls (n = 18) and CRS without nasal polyps (CRSsNP, n = 45). Nasal polyps (NP) and UP were obtained from CRS with nasal polyps (CRSwNP, n = 56). The innate immune cells was evaluated by immunohistochemistry such as, eosinophil major basic protein (MBP), tryptase, CD68, CD163, CD11c, 2D7, human neutrophil elastase (HNE) and its distribution was analyzed according to clinical parameters.

Results

In comparisons between UP from each group, CRSwNP had a higher number of MPB⁺, CD68⁺, and CD11c⁺ cells relative to CRSsNP. Comparisons between UP and NP from CRSwNP indicated that NP have a higher infiltrate of MBP⁺, CD163⁺, CD11c⁺, 2D7⁺ and HNE⁺ cells, whereas fewer CD68⁺ cells were found in NP. In addition, MBP⁺ and CD11c⁺ cells were increased from UP of CRSsNP, to UP of CRSwNP, and to NP of CRSwNP. Moreover, in UP from CRSwNP, the number of MBP⁺ and CD11c⁺ cells positively correlated with CT scores. In the analysis of CRSwNP phenotype, allergic eosinophilic polyps had a higher number of MBP⁺, tryptase⁺, CD11c⁺, 2D7⁺ cells than others, whereas allergic non-eosinophilic polyps showed mainly infiltration of HNE⁺ and 2D7⁺ cells.

Conclusions

The infiltration of MBP⁺ and CD11c⁺ innate immune cells show a significant association with phenotype and disease extent of CRS and allergic status also may influences cellular phenotype in non-asthmatic CRSwNP in Korea.

Increased level of interleukin-13, but not interleukin-4 and interferon-γ in chronic rhinosinusitis with nasal polyps

BACKGROUND

This study was performed to investigate the serum level of interleukin (IL)-13, IL-4, and interferon (IFN)-γ in chronic rhinosinusitis with nasal polyps (CRSwNP) and subsequent inflammation pattern and comorbidities including asthma and aspirin intolerance.

METHODS

A case-control study was conducted on 60 adult patients with CRSwNP with mean age of 37.7±12.7 (ranging from 18 to 70) years, and on 20 healthy controls. Serum levels of IL-13, IL-4, and IFN-γ were assessed, using enzyme-linked immunosorbent assay to be compared between case and control groups. Serum level of total immunoglobulin (Ig) E was also assessed in the patients with CRSwNP.

RESULTS

Serum level of IL-13 in the patients with CRSwNP was significantly higher than the controls (0.98±1.56 vs. 0.34±0.16 pg/ml, respectively, p=0.002). IL-4 and IFN-γ did not differ significantly between the two groups. Total IgE level was significantly increased in the patients with CRSwNP, compared to the normal values (301.43±516.54 IU/ml, p=0.033). Among the patients with CRSwNP, 12/60 (20%) had aspirin intolerance and 44/60 (73.3%) had asthma. IgE was also higher in asthmatics than non-asthmatics patients (364.9±586.6 vs. 126.7±135.7, respectively, p=0.015). Patients with aspirin intolerance had higher levels of IFN-γ (4.7±1.4 vs. 4.1±0.6, respectively, p=0.022).

CONCLUSIONS

IL-13 with high level of total IgE was observed in the patients with CRSwNP, which predisposes them to have concomitant asthma. IFN-γ seems to be down-regulated in the patients with CRSwNP, but could be over-expressed in the presence of aspirin intolerance.

Cigarette smoke exposure is associated with vitamin D3 deficiencies in patients with chronic rhinosinusitis

BACKGROUND

Cigarette smoke (CS) plays a role in the exacerbation of chronic rhinosinusitis (CRS); however, the mechanism for this is unknown. We hypothesize that CS impairs human sinonasal epithelial cell (HSNEC) conversion of 25(OH)D3 (25VD3) to 1,25-dihydroxyvitamin D3 (1,25VD3) and, furthermore, that supplementation with 1,25VD3 will reverse smoke-induced inflammatory responses by HSNECs.

OBJECTIVE

We sought to determine the effect of CS on vitamin D3 (VD3) levels, conversion, and regulation of CS-induced inflammation in control subjects and patients with CRS.

METHODS

Blood and sinus tissue explants were collected at the time of surgery from control subjects, patients with chronic rhinosinusitis without nasal polyps, and patients with chronic sinusitis with nasal polyps (CRSwNP). Expression of VD3 metabolizing enzymes were measured by using RT-PCR. Primary HSNECs were cultured from tissue explants. 25VD3 with and without cigarette smoke extract (CSE) was used to examine conversion of 25VD3 to 1,25VD3, as well as HSNEC production of proinflammatory cytokines.

RESULTS

CS exposure was associated with reduced circulating and sinonasal 25VD3 levels in all groups compared with those seen in CS-naive, disease-matched counterparts. CS exposure decreased expression of CYP27B1 and was especially pronounced in patients with CRSwNP. CSE impairs control HSNEC conversion of 25VD3. HSNECs from patients with CRSwNP also demonstrate an intrinsic reduction in conversion of 25VD3 to 1,25VD3. Exogenous 1,25VD3 reduces CSE-induced cytokine production by HSNECs.

CONCLUSIONS

Exposure to CS is associated with reduced 25VD3 levels and an impaired ability of HSNECs to convert 25VD3 to 1,25VD3. Addition of 1,25VD3 reduces the proinflammatory effects of CS on HSNECs. Impaired VD3 conversion by CS exposure represents a novel mechanism through which CS induces its proinflammatory effects.

The expression of dendritic cell subsets in severe chronic rhinosinusitis with nasal polyps is altered

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized as a Th2-driven disease. Activated dendritic cells (DCs) are the main T-cell activators; their role in the chronic inflammatory process of nasal polyposis is still unclear.

METHODS

The regulation of DC subsets was analyzed in nasal polyp tissue from CRSwNP patients and compared to inferior turbinate tissue from healthy subjects. Tissue localization and expression of both plasmacytoid and myeloid DCs were assayed by means of immunohistochemistry and flow cytometry. Plasmacytoid DCs were also assayed by PCR, and tissue homogenates were assayed for various inflammatory markers.

RESULTS

The number of plasmacytoid (pDCs) and myeloid (mDCs) dendritic cells was significantly increased in nasal polyp tissue when compared to non-inflamed nasal mucosa. The number of pDCs, but not mDCs, was down-regulated in more severe cases (nasal polyps with asthma) and varied with the cytokine milieu. The amount of pDCs was significantly decreased in IL5+IFNγ - nasal polyp tissue compared to tissues with high IFNγ levels (IL5+IFNγ+). Furthermore, levels of indoleamine 2,3-dioxygenase were increased in nasal polyp compared to inferior turbinate tissue and correlated negatively with the number of pDCs.

CONCLUSIONS

There is an altered balance of pDC and mDC numbers in nasal polyp tissue. pDCs seem to be more susceptible to an inflammatory cytokine milieu and may play a crucial role in disease severity.

Macrophage Infiltrate Is Elevated in CRSwNP Sinonasal Tissue Regardless of Atopic Status

Objective

Macrophages are major producers of inflammatory cytokines; however, their role in chronic rhinosinusitis (CRS) has not been clearly defined. The aim of this study was to quantify macrophages in sinus tissue of patients with various subtypes of CRS and determine the impact of atopic status on macrophage infiltrate.

Study Design

Prospective immunohistochemical study of human sinonasal tissue.

Setting

Academic medical center.

Subjects and Methods

Human sinonasal tissue was taken from patients with CRS with nasal polyposis (CRSwNP, n = 8), CRS without nasal polyposis (CRSsNP, n = 8), and controls (n = 8) undergoing surgery for CSF leak repair or endoscopic excision of non-secreting pituitary tumor. Samples were immunohistochemically stained for macrophage/monocyte markers Mac387 and CD68.

Results

CRSwNP patients had significantly increased numbers of Mac387 and CD68 cells compared to control patients ( P < .05) or CRSsNP patients ( P < .01). CRSsNP had significantly increased number of cells staining for CD68 compared to controls ( P < .05). The increased presence of macrophages measured by either marker in CRSwNP was independent of atopic status.

Conclusion

Macrophages are increased in CSRwNP patients regardless of atopic status and may contribute to the immunopathology of CRS.

Gaucher disease: chemotactic factors and immunological cell invasion in a mouse model

Gaucher disease results from mutations in GBA1 that cause functional disruption of the encoded lysosomal enzyme, acid β-glucosidase. The consequent excess accumulation of glucosylceramide and glucosylsphingosine in lysosomes is central to the disease pathogenesis with classical involvement of macrophage (Mфs) lineage cells of visceral organs, bone, or brain. Several studies have implicated the increased secretion of chemokines and infiltration of a variety of immunological cells into tissues of Gaucher disease patients. Trafficking of immunological cells to the sites of inflammation requires the presence of chemokines. Although increases of different immunological cells and several chemokines are present in Gaucher disease, the specific chemoattractants that cause the increased influx of immunological cells are not fully defined. Here, increased levels of I-309, MCP-5, CXCL-2, CXCL-9, CXCL-10, CXCL-11, CXCL-13, and their corresponding leukocytes, i.e., MOs (monocytes), Mфs, dendritic cells (DCs), polymorphonuclear neutrophils (PMNs), and T, and B cells were identified in the circulation of mice with Gba1 mutations (D409V/null). Sera from D409V/null mice contained chemoattractants for a variety of immunological cells as shown by ex vivo chemotaxis studies and by flow cytometry. Enhanced chemotaxis towards 9V/null sera was found for 9V/null lung-, spleen-, liver-, and bone marrow-derived Mфs (CD11b(+) F480(+)), PMNs (Gr1(high) CD11b(+)), DCs (CD11c(+) CD11b(+)), T lymphocytes (CD3(+) TCRB(+)), and B lymphocytes (B220(+) CD19(+)). These data support these chemotactic factors as causative to increased tissue infiltration of leukocytes in Gaucher disease.

Systemic monocyte-derived dendritic cells and associated Th2 skewing in chronic rhinosinusitis

INTRODUCTION

Monocyte-derived dendritic cells (moDCs) are antigen-presenting cells capable of directing immune responses toward T-helper 1 (Th1) or T-helper 2 (Th2) phenotypes. The systemic profile of moDCs and their association with Th1/Th2 skewing in chronic rhinosinusitis (CRS) is unclear. The purpose of this study is to characterize circulating moDCs in controls, CRS without nasal polyps (CRSsNP), and CRS with nasal polyps (CRSwNP) and correlate moDCs with Th1/Th2 skewing, mucosal inflammation on computed tomography (CT), and quality of life (QoL).

STUDY DESIGN

Cross-sectional study.

SETTING

Tertiary care hospital.

SUBJECTS

Blood was drawn from control (n = 12), CRSsNP (n = 18), and CRSwNP (n = 15) patients during endoscopic sinus surgery.

METHODS

Peripheral blood moDCs were analyzed with flow cytometry for expression of HLA-DR, CD209, and CD14. Th1 and Th2 cells were identified by CXCR3 and CCR8 expression, respectively. Lund-Mackay CT scores were assigned by blinded graders. Sino-Nasal Outcome Test 22 (SNOT-22) surveys were completed by patients before surgery.

RESULTS

CRSsNP and CRSwNP displayed elevations in systemic moDCs compared with controls. In CRSwNP, systemic Th2 skewing was observed and circulating CD4+ Th2 cells correlated with percent moDCs. MoDCs strongly correlated with higher Lund-Mackay CT scores in CRSsNP but not in CRSwNP. No relationship between moDCs and SNOT-22 scores was observed for either subset of CRS.

CONCLUSION

These data support that CRSwNP and CRSsNP display alterations in systemic immune profiles. CRSwNP is characterized by significant elevations in circulating moDCs, which is associated with systemic Th2-biased inflammation. Circulating moDCs are associated with mucosal inflammation on CT imaging in CRSsNP. No association between moDCs and QoL is evident in either CRS subset.

Systemic prednisone administration selectively alters granulocyte subsets in nasal polyps from aspirin-exacerbated respiratory disease and chronic rhinosinusitis patients

BACKGROUND

Nasal polyps (NPs) are hallmark inflammatory lesions of sinusitis. Despite the spectrum of NP conditions, cellular differences between NPs from patients with chronic rhinosinusitis with NPs (CRSwNP) and aspirin-exacerbated respiratory disease (AERD) are poorly understood. NPs are associated with abundant eosinophils; the contributions of neutrophil and basophil granulocytes are less defined. We therefore sought to assess granulocyte subpopulations, and differential effects following prednisone pretreatment, within NPs of CRSwNP and AERD patients.

METHODS

NPs, adjacent ethmoid sinus tissue, and peripheral blood mononuclear cells (PBMCs) were obtained from patients undergoing endoscopic sinus surgery. Samples from 5 cohorts: CRSwNP ± prednisone (n = 6 each), AERD ± prednisone (n = 6 each), and controls (n = 9), were analyzed by high-dimensional flow cytometry to gate granulocyte populations. Specimens were also assessed using immunohistochemistry (IHC) staining.

RESULTS

Systemic prednisone administration was associated with a lower frequency of eosinophils (p < 0.0001, n = 6) in NPs in both CRSwNP and AERD patients, whereas a decrease in neutrophils (p = 0.0070, n = 6) in NPs was only observed in CRSwNP patients after prednisone treatment. In contrast, steroids do not alter basophil proportions (p = 0.48, n = 6) within NPs from either group. No significant shift in granulocyte subsets after steroid treatment was identified in the adjacent ethmoid mucosa or PBMCs from the same patients. Immunohistochemistry (IHC) staining supported these findings.

CONCLUSION

Granulocyte subpopulations are focally affected within NPs by systemic steroid exposure, without notable granulocyte alterations in the surrounding regional tissues. These data provide direct insights into the cellular effects of routine prednisone exposure in CRS patients, and highlight a unique microenvironment present within NP lesions.

Effects of intranasal steroid treatment on the presence of biofilms in non-allergic patients with chronic rhinosinusitis with nasal polyposis

Microbial biofilms have been implicated in the pathogenesis of chronic rhinosinusitis with nasal polyposis (CRSwNP). Intranasal application of corticosteroids (INCS) is a reliable option in the management of CRSwNP. INCS medication has been suspected to influence the presence and thickness of microbial biofilms and inflammatory cell patterns in CRSwNP. Two series of identical nasal polyps obtained from non-allergic patients with CRSwNP (n = 56), who underwent endoscopic sinus surgery (ESS), were processed to hematoxylin-eosin (H.E.) and Gram staining, respectively. Patients were recruited into three groups. Group A (n = 21) consisted of patients with continuous preoperative INCS treatment. In group B (n = 17), patients were never treated by INCS, while in group C (n = 18) INCS medication was stopped at least 6 months before ESS. Biofilm positivity varied from 76.4 to 88.8% in different subject groups. These values and average thickness of biofilms did not reach statistically significant levels (Mann-Whitney's U probe, p > 0.05) in different patient groups. In contrast, microscopic pattern and numbers of predominant inflammatory cell populations displayed obvious differences according to INCS treatment (Mann-Whitney's U probe, p < 0.001). According to these observations, INCS treatment does not affect the presence and thickness of microbial biofilms in CRSwNP. In contrast, it has significant effects on the pattern of inflammatory cells infiltrating the subepithelial layer, which might result in beneficially altered extracellular matrix production and cytokine release.

The presence of CD209 expressing dendritic cells correlates with biofilm positivity in chronic rhinosinusitis with nasal polyposis

Biofilm-positive cases of chronic rhinosinusitis with nasal polyposis (CRSwNP) may form a separate clinical entity, which is characterized by high recurrence rates and resistance against different therapeutic strategies. This can be explained by a special immunologic phenotype. Biofilm existence has been supposed to correlate with increased amount of dendritic cells that are responsible for antigen presentation in CRSwNP. A total of 20 patients with CRSwNP undergoing endoscopic sinus surgery (ESS) were analyzed. The negative control group consisted of ten patients undergoing septoplasty without CRSwNP. Three series of individual nasal polyps and control specimens were processed to hematoxylin-eosin (HE) and Gram staining and to CD209-specific immunofluorescent assay, respectively. Biofilm was detected in 13 of 20 patients (65 %) with CRSwNP and in none of the ten negative controls. The subepithelial layer of biofilm-positive nasal polyps displayed a statistically significant (p < 0.001) increase in the numbers of CD209-expressing dendritic cells compared to biofilm-negative specimens. It was found that biofilm detectability showed strong correlation to the architecture of respiratory mucosa and to the dominant inflammatory cell type of the subepithelial layer. Persisting bacterial biofilms may affect the type of antigen presentation and consecutive immune reactions in the subepithelial layer of nasal mucosa. This phenomenon may result in different inflammatory pathways with specific cytokine profile compared to biofilm-negative cases. Co-existence of bacterial biofilms and dominant pattern of dendritic cells suggest a biofilm-associated immunologic phenotype in CRSwNP. This can explain the mucosal changes, functional disorders and therapy resistance featuring CRSwNP.

Vitamin D3 deficiency increases sinus mucosa dendritic cells in pediatric chronic rhinosinusitis with nasal polyps

OBJECTIVE

Dendritic cells are professional antigen presenting cells, capable of initiating Th1 or Th2 responses, and have been implicated in the pathogenesis of a number of diseases, including sinusitis. Vitamin D(3) is a steroid hormone that acts on dendritic cells in a manner similar to corticosteroids. Investigators examined whether children with allergic fungal rhinosinusitis (AFRS) or chronic rhinosinusitis with nasal polyposis (CRSwNP) were vitamin D(3) deficient and the relationship of vitamin D(3) deficiency to dendritic cell infiltrate in the sinus mucosa.

SETTING

Tertiary care university hospital.

STUDY DESIGN

Retrospective, controlled study using samples collected from pediatric patients seen from August 2009 to July 2011.

SUBJECTS AND METHODS

Plasma levels of 25-hydroxy vitamin D(3) were measured by enzyme-linked immunosorbent assay in children (≤18 years old) with AFRS, CRSwNP, or CRS without nasal polyposis (CRSsNP) and in controls undergoing surgery for adenotonsillar hypertrophy. Vitamin D(3) levels were confirmed using clinical diagnostic methods for those with CRSwNP or AFRS. Tissue samples were immunohistochemically stained for the dendritic cell marker CD209 and the costimulatory molecules CD80 and CD86.

RESULTS

There was no difference in mean vitamin D(3) levels between control and CRSsNP, whereas mean CRSwNP and AFRS levels were both well below the minimum recommended level of 30 ng/mL and significantly lower than control and CRSsNP levels. CD209(+) dendritic cells inversely correlated with vitamin D(3) but not costimulatory molecule expression.

CONCLUSIONS

These studies identify that children with CRSwNP or AFRS are vitamin D(3) deficient, which may be linked to increased dendritic cell infiltrate. These results suggest a role for vitamin D(3) as a key player in the immunopathology of pediatric CRSwNP.