Alterations in gene expression of complement components in chronic rhinosinusitis

Exploring the comorbidity association and biological mechanisms of chronic rhinosinusitis and chronic obstructive pulmonary disease

Although chronic rhinosinusitis (CRS) and chronic obstructive pulmonary disease (COPD) are both common chronic inflammatory diseases, the interaction between their comorbidities remains poorly understood within the unified airway disease framework. This study, for the first time, integrated multi-omics analysis and large-scale epidemiological data to explore their common mechanisms and clinical significance. The NHANES database was used for analysis, and multivariate logistic regression was employed to assess the comorbidity risk of CRS and COPD. Machine-learning models (glmnet, ranger, and xgboost) were used to analyze the NHANES data to determine the best model. Subsequently, Mendelian randomization(MR) was applied to explore relevant associations. Additionally, CRS and COPD datasets from GEO were further analyzed to identify potential targets. The NHANES analysis showed a significant association between CRS and COPD, with MR results indicating that CRS significantly increased the risk of COPD. Multi-omics integration revealed that C3 and CD163 are core targets in CRS/COPD patients. The ranger model was identified as the most suitable in this study. This study provides new evidence that CRS is an independent risk factor for COPD and establishes a unified airway mechanism centered on C3-CD163-mediated inflammation. These findings advance the "one airway, one disease" paradigm and support a dual-target therapeutic strategy.

Analysis of competing endogenous RNA (ceRNA) crosstalk in eosinophilic chronic rhinosinusitis with nasal polyps

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) is one of the most common chronic inflammatory diseases, and has various phenotypes. Although its pathophysiology remains obscure, evidence has shown that dysregulation of noncoding RNAs (ncRNAs) is associated with CRSwNP. ncRNAs in the cytoplasm can act as competing endogenous RNAs (ceRNAs), which are involved in many inflammatory processes. However, the ceRNA crosstalk in CRSwNP is still unclear METHODS: We investigated expression profiles of messenger RNA (mRNA), microRNAs (miRNAs), and long noncoding RNAs (lncRNAs) in eosinophilic CRSwNP and constructed a global triple ceRNA network.

RESULTS

As a result, 964 differentially expressed mRNAs (DEmRs), 207 differentially expressed miRNAs (DEmiRs), and 15 differentially expressed lncRNAs (DElncRs) were identified, and a ceRNA network containing 598 miRNA-mRNA pairs and 70 lncRNA-miRNA pairs was finally constructed. Gene set enrichment analysis (GSEA) results indicated these DEmRs were mainly enriched in "cytokine-cytokine receptor interaction," "salivary secretion," "hematopoietic cell lineage," and "chemokine signaling pathway." Moreover, we also predicted the subcellular localization of the DElncRs identified in the network via bioinformatics approaches  CONCLUSION: In summary, the present study provided the first comprehensive assessment of the ceRNA crosstalk in eosinophilic CRSwNP. These findings will be of interest to the understanding of the potential pathophysiology of this disease.

Increased Thrombin-Activatable Fibrinolysis Inhibitor in Response to Sublingual Immunotherapy for Allergic Rhinitis

OBJECTIVES/HYPOTHESIS

The objective of this study was to determine the role of thrombin-activatable fibrinolysis inhibitor (TAFI) as a candidate biomarker for therapeutic efficacy of sublingual immunotherapy (SLIT) and to identify the role of TAFI in the pathogenesis of allergic rhinitis (AR).

STUDY DESIGN

Retrospective cohort study and laboratory study.

METHODS

Serum was collected from patients with allergies to Japanese cedar pollen before, during, and after treatment with SLIT. We measured the levels of immunoreactive TAFI, C3a, and C5a in serum by enzyme-linked immunosorbent assay (ELISA) and assessed their relative impact on a combined symptom-medication score. We also examined the impact of TAFI on mast cells and fibroblasts in experiments performed in vitro.

RESULTS

Serum levels of TAFI increased significantly in response to SLIT. By contrast, serum C3a levels decreased significantly over time; we observed a significant negative correlation between serum levels of TAFI versus C3a and symptom-medication score. Mast cell degranulation was inhibited in response to TAFI, as it was the expression of both CCL11 and CCL5 in cultured fibroblasts.

CONCLUSIONS

High serum levels of TAFI may be induced by SLIT. TAFI may play a critical protective role in pathogenesis of AR by inactivating C3a and by inhibiting mast cell degranulation and chemokines expression in fibroblasts.

LEVEL OF EVIDENCE

4 Laryngoscope, 2021.

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.

Linking Complement C3 and B Cells in Nasal Polyposis

Nasal polyposis often is characterized by a persistent inflammation of the sinonasal mucosa, disease recurrence after medical or surgical intervention, and asthma comorbidity. Dysregulated complement activation may contribute to immunologic alterations and disease. To date, there is only scattered knowledge on the source and regulation of the central complement factors in the pathogenesis of nasal polyps. Here, we aim to study complement signatures, especially the C3-C3aR axis, and focus on cellular sources and targets in nasal polyps. Expression of complement factors, including C3, C5, and the anaphylatoxin receptors, was analyzed in nasal polyp tissue samples, the corresponding inferior turbinates, and healthy controls using transcriptomic methods and protein measurements. Distinct patterns of complement expression were found in nasal polyps compared to controls, characterized by an increased C3 activation and an increase in C3aR-bearing cells. In contrast, no difference was shown for epithelial-dependent C3 production. Besides low intracellular C3-expression levels for lymphocytes in general, we could identify an enlarged B lymphocyte population in nasal polyps displaying high amounts of intracellular C3. Our data suggest a prominent role for the C3-C3aR-axis in nasal polyps and, for the first time, describe a B cell population containing high levels of intracellular C3, suggesting a new role of B cells in the maintenance of the inflammation by complement.

Prognostic Significance of Serum Complement Component 3 in Chronic Rhinosinusitis with Nasal Polyps

OBJECTIVE

The aim of this study was to assess the relationship between serum complement component 3 (C3) levels and disease recurrences in patients with chronic rhinosinusitis with nasal polyps (NPs).

METHODS

Ninety-seven patients with NPs and 30 controls were recruited. Clinical features were collected. Serum concentrations of C3 and C4 were measured before and after endoscopic sinus surgery.

RESULTS

Compared to the controls, increased C3 levels were found in patients with NPs. Patients with polyp recurrences had higher pre- and postoperative serum C3 levels than patients without polyp recurrences. Serum C3 levels dropped after surgery. After polyp regrowth, the mean C3 level in the recurrent group elevated again to the degree similar to that before surgery. When patients were stratified by tissue eosinophilia, no significant difference was seen in pre-/postoperative, absolute change after surgery, and post-recurrent C3 levels between patients without and with eosinophilic NPs in the group with disease recurrences.

CONCLUSION

Serum C3 may be involved in the pathogenesis of NPs. Higher serum C3 levels may pinpoint patients at high risk of recurrence as an independent factor. Furthermore, the change in C3 levels after surgery may have the potential to serve as a predictor for polyp progression. Adding serum C3 measurement to the routine walk-up in the clinical management of NPs is worth further investigation and may help physicians make a more rational diagnostic and/or therapeutic decision regarding this disease.

Allergic fungal rhinosinusitis

Allergic fungal rhinosinusitis (AFRS) is a subset of chronic rhinosinusitis with nasal polyps (CRSwNP) characterized by antifungal IgE sensitivity, eosinophil-rich mucus (ie, allergic mucin), and characteristic computed tomographic and magnetic resonance imaging findings in paranasal sinuses. AFRS develops in immunocompetent patients, with occurrence influenced by climate, geography, and several identified host factors. Molecular pathways and immune responses driving AFRS are still being delineated, but prominent adaptive and more recently recognized innate type 2 immune responses are important, many similar to those established in patients with other forms of CRSwNP. It is unclear whether AFRS represents merely a more extreme expression of pathways important in patients with CRSwNP or whether there are other disordered immune responses that would define a distinct endotype or endotypes. Although AFRS and allergic bronchopulmonary aspergillosis share some analogous immune mechanisms, the 2 conditions do not occur commonly in the same patient. Treatment of AFRS almost always requires surgical debridement of the involved sinuses. Oral corticosteroids decrease recurrence after surgery, but other adjunctive pharmacologic agents, including topical and oral antifungal agents, do not have a firm evidence basis for use. There is good rationale for use of biologic agents that target eosinophilic inflammation or other type 2 responses, but studies in patients with AFRS are required.

Contribution of Epithelial Cell Dysfunction to the Pathogenesis of Chronic Rhinosinusitis with Nasal Polyps

Background

In the past, the airway epithelium was thought to be primarily an inert physical barrier. We now know that the upper airway epithelium plays a critical role in both innate and adaptive immunity, and that epithelial dysfunction is strongly associated with inflammatory airway disease. The pathogenesis of chronic rhinosinusitis is poorly understood, but growing evidence supports a key role for the airway epithelium in the pathophysiology of the disease.

Objective

The purpose of this study is to explore our current understanding of how dysfunction in human sinonasal epithelial cells (HSNECs) contributes to the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP) and to examine how current and developing therapies affect epithelial cell functions.

Methods

A literature review of papers published in English pertaining to epithelial cell dysfunction in patients with CRSwNP was performed using the PubMed database. The search utilized combinations of the following key words: sinusitis, polyps, epithelium, pathophysiology, barrier function, dendritic cells, eosinophils, T cells, complement, mucociliary clearance, vitamin D, cytokines, chemokines, taste receptors, steroids, saline, and therapy.

Results

HSNEC mucociliary clearance, barrier function, secretion of cytokines, influence on dendritic cells, influence on T-cells, regulation of eosinophils, vitamin D metabolism, complement production, and taste receptor function are altered in patients with CRSwNP and contribute to the pathogenesis of the disease. Current therapies utilized to manage CRSwNP counteract the effects of HSNEC dysfunction and relieve key symptoms of the disease.

Conclusion

HSNECs are key players in both innate and adaptive immunity, and altered epithelial functions are closely intertwined with the pathogenesis of CRSwNP. Our review supports further investigation of altered HSNEC function in patients with CRSwNP and supports development of novel epithelial-targeted therapies for its management.

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.

Genetic and Immune Dysregulation in Chronic Rhinosinusitis

Chronic rhinosinusitis (CRS) is a prevalent condition that is heterogeneous in disease characteristics and multifactorial in cause. Although sinonasal mucosal inflammation in CRS is often either reversible or well-managed medically and surgically, a significant proportion of patients has a refractory form of CRS despite maximal therapy. Two of the several described factors thought to contribute to disease recalcitrance are genetic influences and dysfunction of the host immune system. Current evidence for a genetic basis of CRS is reviewed, as it pertains to putative abnormalities in innate and adaptive immune function. The role of systemic immunodeficiencies in refractory CRS is discussed.

Classical complement pathway activation in the nasal tissue of patients with chronic rhinosinusitis

BACKGROUND

Complement plays a major role in inflammatory diseases, but its involvement and mechanisms of activation in patients with chronic rhinosinusitis (CRS) are not known.

OBJECTIVES

After earlier studies discovering autoantibodies in patients with CRS, we sought to investigate the nature, extent, and location of complement activation in nasal tissue of patients with CRS. Specifically, we were interested in whether antibody-mediated activation through the classical pathway was a major mechanism for complement activation in patients with CRS.

METHODS

Nasal tissue was obtained from patients with CRS and control subjects. Tissue homogenates were analyzed for complement activation products (ELISA-C5b-9, C4d, activated C1, and C5a) and major complement-fixing antibodies (Luminex). Tissue sections were stained for C5b-9, C4d, and laminin. Antibodies were purified with protein A/G columns from nasal polyps (NP), matching patient serum, and control serum and assayed for basement membrane binding by means of ELISA.

RESULTS

C5b-9 levels were significantly increased in NP tissue compared with uncinate tissue (UT) of patients with chronic rhinosinusitis with nasal polyps (CRSwNP) and those with chronic rhinosinusitis without nasal polyps (CRSsNP; P < .01). Similarly, C4d levels were increased in NPs compared with UT of patients with CRSwNP, patients with CRSsNP, and control subjects (P < .05). Activated C1 levels were also increased in NP tissue compared with UT of patients with CRSsNP and control subjects (P < .05) and correlated with levels of C5a (P < .01), local immunoglobulins (especially IgM, P < .0001), and anti-double-stranded DNA IgG (P < .05). Immunofluorescence showed that C5b-9 and C4d deposition occurred linearly along the epithelial basement membrane. NP tissue extracts had significantly more anti-basement membrane antibodies than sera from patients with CRSwNP and control subjects (P < .0001).

CONCLUSION

Levels of C5b-9, C4d, and activated C1 were significantly increased locally in NP tissue. C5b-9 and C4d were almost universally deposited linearly along the basement membrane of NP tissue. Furthermore, activated C1 levels were best correlated with local immunoglobulin and C5a levels. Together, these data suggest that the classical pathway plays a major role in complement activation in patients with CRS.

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.

Recalcitrant rhinosinusitis, innate immunity, and mannose-binding lectin

BACKGROUND

Mannose-binding lectin (MBL) is a protein produced by the liver that participates in innate immunity by tagging the surface of microbes for opsonization. Mannose-binding lectin deficiency is present in 7% of the population and has been implicated in recurrent respiratory tract infections in children. Mannose-binding lectin deficiency has not been explored in rhinosinusitis but is associated with increased mortality in adult pneumococcal infection. The purpose of this report is to describe a tertiary rhinology patient experience with MBL deficiency and recalcitrant rhinosinusitis.

METHODS

This retrospective case series report characterizes predominantly adult patients with low MBL levels from January 2010 to June 2012. Indications for MBL testing, sinus culture data, immunological testing results, and treatments used to control rhinosinusitis are described.

RESULTS

Mannose-binding lectin levels were deficient in 12 of 36 patients (33.3%) tested. IgG subclasses were abnormally low in 5 of 12 patients; IgA was normal in 11 of 12 patients; and IgM was normal in 11 of 12 patients. Staphylococcus aureus, coagulase-negative Staphylococcus species, and Pseudomonas aeruginosa, known to be "tagged" by MBL, were the most common organisms grown on culture. Treatments included culture directed systemic antimicrobial therapy and topical steroids/antibiotics.

CONCLUSION

Mannose-binding lectin, an important component of the lectin complement pathway and innate immunity, is possibly associated with recalcitrant adult rhinosinusitis. Steroid/antibiotic irrigations appear to benefit patients with recalcitrant rhinosinusitis and possibly those with MBL deficiency. Given that the prevalence of MBL deficiency in this case series is 4 times that seen in the normal population, additional investigations are warranted to further elucidate the role of MBL deficiency in rhinosinusitis.

Host-microbial interactions in patients with chronic rhinosinusitis

There has been considerable investigation of host-microbial interactions in patients with chronic rhinosinusitis (CRS) in hopes of elucidating mechanisms of disease and better treatment. Most attention has been paid to bacterial infection and potential underlying defects in innate immunity. Bacterial biofilm is present in most patients with CRS undergoing surgical intervention, and its presence is associated with more severe disease and worse surgical outcomes. A role for viral or fungal infection in patients with CRS is less clear. There is no evidence for a primary defect in mucociliary clearance in most patients with CRS. Decreased levels of certain antimicrobial proteins, most notably lactoferrin, have been found in sinus secretions, whereas levels of other antimicrobial proteins have been found to be normal. No primary defects in Toll-like receptors have been found in patients with CRS, although a 50% reduced expression of Toll-like receptor 9 was reported in patients with recalcitrant nasal polyps. A polymorphism in a bitter taste receptor was recently associated with refractory CRS and persistent Pseudomonas aeruginosa infection. A downregulation of innate immunity by maladaptive T_H2 tissue inflammation has also been described in patients with recalcitrant nasal polyps, suggesting a link to persistent infection. To date, an effective means of restoring host-microbial balance and mitigating disease in patients with CRS remains elusive.

Immunopathology features of chronic rhinosinusitis in high-altitude dwelling Tibetans

Chronic rhinosinusitis (CRS) presents distinct inflammatory and remodeling patterns in different populations and environments. Tibetan ethnic groups live at high altitudes and in cold weather conditions. We sought to examine whether Tibetans exhibit distinct CRS pathology or characteristics. Sinonasal polyps and mucosal tissue were obtained from 14 Tibetan patients with CRS and nasal polyps (CRSwNPs), 13 patients with CRS without nasal polyps (CRSsNPs), and 12 Tibetan controls. Tissue homogenates and serum samples were assayed for several T-helper (TH) cell cytokines and mediators using enzyme linked immunosorbent assay profiles were measured using quantity polymerase chain reaction. Several key inflammatory cells were examined for immunohistochemical markers. CRSwNPs were characterized by increased mediator promoting eosinophilic inflammation (interleukin [IL]-5, eosinophil cationic protein, and total immunoglobulin E) and slight synergism with expression of IL-8, IL-2sRa, IL-1beta, IL-6, and myeloperoxidase, and a predominance of eosinophils, mast cells, and neutrophils. GATA-3 transcription factor was significantly increased and Foxp3 showed a tendency to be impaired in CRSwNPs compared with controls. CRSsNPs were characterized by significantly high levels of transforming growth factor beta1, increased interferon γ, and a significant enhancement of Foxp3 and T-beta compared with CRSwNPs. There were reduced numbers of inflammatory cells but increased levels of macrophages in CRSsNPs. Compared with CRSsNPs, CRSwNPs present a severe inflammatory reaction and show a TH2 milieu with apparently impaired regulatory T cells (Treg) function and increased inflammatory cells infiltration predominated by eosinophilic and mast cells. In contrast, TH1 polarization with enhanced Treg function and increased levels of macrophages appear in CRSsNPs.

Feline degenerative joint disease: a genomic and proteomic approach

The underlying disease mechanisms for feline degenerative joint disease (DJD) are mostly unidentified. Today, most of what is published on mammalian arthritis is based on human clinical findings or on mammalian models of human arthritis. However, DJD is a common occurrence in the millions of domestic felines worldwide. To get a better understanding of the changes in biological pathways that are associated with feline DJD, this study employed a custom-designed feline GeneChip, and the institution's unique access to large sample populations to investigate genes and proteins from whole blood and serum that may be up- or down-regulated in DJD cats. The GeneChip results centered around three main pathways that were affected in DJD cats: immune function, apoptosis and oxidative phosphorylation. By identifying these key disease-associated pathways it will then be possible to better understand disease pathogenesis and diagnose it more easily, and to better target it with pharmaceutical and nutritional intervention.

Gene expression signatures: a new approach to understanding the pathophysiology of chronic rhinosinusitis

Chronic rhinosinusitis (CRS) is a complex inflammatory disease with variable disease manifestation. Though external risk factors are associated with development and/or persistence of CRS, the host mucosal response is also important, as nasal epithelium acts as a physical and immune barrier. Under inflammatory stress, the nasal epithelium can undergo injury, followed by a rapid remodeling response ranging from epithelial hyperplasia, to goblet-cell metaplasia, to denudation, loss of cilia, fibrosis, and basement membrane thickening. Identification of gene expression signatures and molecular pathways in CRS pathogenesis have now begun to contribute significantly to a better understanding of the genetic and molecular alterations underlying CRS development and progression. Genetic studies are especially illuminating when multiple gene variants synergize within a permissive environmental context, and are expected to guide development of more effective therapeutic targets for CRS treatment.

Role of innate immunity in the pathogenesis of chronic rhinosinusitis: progress and new avenues

Chronic rhinosinusitis is a heterogeneous and multifactorial disease with unknown etiology. Aberrant responses to microorganisms have been suggested to play a role in the pathophysiology of the disease. Research has focused on the presence, detection, response to, and eradication of these potential threats. Main topics seem to center on the contribution of structural cells such as epithelium and fibroblasts, on the consequences of activation of pattern-recognition receptors, and on the role of antimicrobial agents. This research should be viewed not only in the light of a comparison between healthy and diseased individuals, but also in a comparison between patients who do or do not respond to treatment. New players that could play a role in the pathophysiology seem to surface at regular intervals, adding to our understanding (and the complexity) of the disease and opening new avenues that may help fight this incapacitating disease.

Complement defects in patients with chronic rhinosinusitis

The complement system is an important part of our immune system, and complement defects lead generally to increased susceptibility to infections and autoimmune diseases. We have studied the role of complement activity in relation with chronic rhinosinusitis (CRS), and more specifically studied whether complement defects collectively predispose individuals for CRS or affect CRS severity. The participants comprised 87 CRS patients randomly selected from the general population, and a control group of 150 healthy blood donors. The CRS patients were diagnosed according to the European Position Paper on Rhinosinusitis and nasal Polyps criteria, and severity was evaluated by the Sino-nasal Outcome Test-22. Serum samples were analysed by ELISA for activity of the respective pathways of complement, and subsequently for serum levels of relevant components. We found that the frequency of complement defects was significantly higher among CRS patients than among healthy control subjects. A majority of Mannan-binding lectin deficient CRS patients was observed. The presence of complement defects had no influence on the severity of subjective symptoms. Our studies show that defects in the complement system collectively may play an immunological role related to the development of CRS. However, an association between severity of symptoms and presence of complement defects could not be demonstrated.

The Effects of Corticosteroid on Tissue Lactoferrin in Patients with Nasal Polyposis

Background

Although, lactoferrin (LF) is the second most important antimicrobial and anti-inflammatory peptide after lysozyme in upper respiratory tract, little is known about its role in chronic rhinosinusitis (CRS). Recent studies pronounced that LF levels were significantly reduced in CRS with nasal polyposis (NP) compared with other subgroups. However, effects of systemic corticosteroid (CS) treatment, which is currently the main NP treatment modality, and subsequent surgical intervention on LF levels are still not known. This study was designed to evaluate the effects of CS treatment and surgical intervention on LF levels in patients with NP.

Methods

Patients with inflammatory NP who were scheduled to undergo CS treatment and a control group were included in this study. LF levels were determined from mucosal samples taken from both groups, before and after CS treatment, and also 1 month after surgical intervention.

Results

Twenty-seven patients with NP and 14 patients who underwent septoplasty were included in the study. Tissue LF levels were significantly lower in the NP group compared with the control group (p = 0.014). Tissue LF levels did not change significantly in NP patients after CS treatment. However, a significant reduction in tissue LF was detected 1 month after endoscopic sinus surgery.

Conclusion

Tissue LF concentrations significantly decreased in patients with NP. CS treatment had no effect on tissue LF levels, whereas postendoscopic sinus surgery, tissue LF levels were getting lower because there was also a reduction in inflammatory load (whether from reduction in mucosa surface area or resolution of disease).

Evidence for intranasal antinuclear autoantibodies in patients with chronic rhinosinusitis with nasal polyps

BACKGROUND

Chronic rhinosinusitis (CRS) with nasal polyps is an inflammatory condition of the nasal passage and paranasal sinuses characterized by T(H)2-biased inflammation with increased levels of B-cell activating factor of the TNF family (BAFF), B lymphocytes, and immunoglobulins. Because high levels of BAFF are associated with autoimmune diseases, we assessed for evidence of autoimmunity in patients with CRS.

OBJECTIVES

The objective of this study was to investigate the presence of autoantibodies in sinonasal tissue from patients with CRS.

METHODS

Standardized nasal tissue specimens were collected from patients with CRS and control subjects and assayed for immunoglobulin production, autoantibody levels, tissue distribution of immunoglobulins, and binding potential of antibodies in nasal tissue with a multiplexed autoantibody microarray, ELISA, and immunofluorescence.

RESULTS

Increased levels of several specific autoantibodies were found in nasal polyp tissue in comparison with levels seen in control tissue and inflamed tissue from patients with CRS without nasal polyps (P < .05). In particular, nuclear-targeted autoantibodies, such as anti-dsDNA IgG and IgA antibodies, were found at increased levels in nasal polyps (P < .05) and particularly in nasal polyps from patients requiring revision surgery for recurrence. Direct immunofluorescence staining demonstrated diffuse epithelial and subepithelial deposition of IgG and increased numbers of IgA-secreting plasma cells not seen in control nasal tissue.

CONCLUSIONS

Autoantibodies, particularly those against nuclear antigens, are present at locally increased levels in nasal polyps. The presence of autoantibodies suggests that the microenvironment of a nasal polyp promotes the expansion of self-reactive B-cell clones. Although the pathogenicity of these antibodies remains to be elucidated, the presence of increased anti-dsDNA antibody levels is associated with a clinically more aggressive form of CRS with nasal polyps requiring repeated surgery.

Distribution of Inflammatory Cells, Adhesion Molecules, Intermediate Filaments, and Chemokine Receptors in Subgroups of Nasal Polyp Patients

Background

The pathogenesis of nasal polyps (NPs) is incompletely understood. The aim of this study was to investigate the distribution of inflammatory cells, adhesion molecules, intermediate filaments, and chemokine receptors in subgroups of NP patients.

Methods

In total, 35 patients were enrolled (group 1, 10 patients with Samter syndrome; group 2, 10 patients with diffuse polyposis without signs of Samter syndrome; group 3: 5 patients with solitary nasal polyps; group 4, 10 controls). Immunohistochemical staining was performed for CD105, CD106, CD62E, CD4, CD8, CXCR4, CD147, CD90, CD104, BF45, vimentin, pancytokeratin, and muscle-specific actin (MSA) in all patients’ specimens.

Results

Expression of CD4, CD8, and CD106 were similar between the groups. Number of patients expressing CD4 in groups 1, 2, and 3 were higher than the controls. Number of patients expressing CD8 antigen were significantly higher in all three groups than in the control group. Expression of CD147 in groups 3 and 4 was significantly higher than in groups 1 and 2. CD98 expression was higher in groups 1, 2, and 3 than in group 4. The number of patients expressing vimentin in groups 1, 2, and 3 was significantly higher than in group 4. Immunostaining for pancytokeratin was positive in all patients.

Conclusion

In conclusion, inflammatory cell, adhesion molecule, intermediate filament, and chemokine receptor profiles in nasal polyps differ among different patient groups and control subjects. Additional specific immunohistochemical studies are necessary for development of more specific immunotherapies.

Chronic rhinosinusitis as a multifactorial inflammatory disorder

Chronic rhinosinusitis (CRS) is a prevalent health condition characterized by sinonasal mucosal inflammation lasting at least 12 weeks. Heterogeneous in clinical presentation, histopathology, and therapeutic response, CRS represents a spectrum of disease entities with variable pathophysiology. Increased knowledge of cellular and molecular derangements in CRS suggests potential etiologies and targets for therapy. Microbial elements including fungi, staphylococcal enterotoxin, and biofilms have been implicated as inflammatory stimuli, along with airborne irritants and allergens. Defects in innate immunity have gained increased attention as contributors to the chronic inflammatory state. A combination of host susceptibility and environmental exposure is widely believed to underlie CRS, although direct evidence is lacking. Presently, without precise disease definitions and identifiable universal triggers, CRS pathogenesis is broadly described as multifactorial. Current research is beginning to unravel complex and diverse effects of chronic inflammation on sinonasal mucosal homeostasis, but dysfunctional pathways of inflammatory regulation and resolution require further elucidation.

The role of complement in the diagnosis and management of allergic rhinitis and allergic asthma

Allergic rhinitis and asthma are common chronic inflammatory diseases of the nasal mucus membranes and the upper airways with a high prevalence in Western countries. In addition to maladaptive T-helper type 2 (Th2) immunity, Th17 cells can drive the inflammatory responses in both diseases. Several reports have shown that the complement system is activated locally and systemically in allergic rhinitis and/or allergic asthma patients. Importantly, recent findings in experimental models of allergic rhinitis and allergic asthma suggest that the complement cleavage products complement 3a and complement 5a and the activation of their corresponding receptors in antigen-presenting cells regulate the development of maladaptive Th2 and Th17 immunity. These findings in experimental asthma are corroborated by genome-wide searches and candidate gene studies in humans. We discuss recent findings in experimental and human allergic airway diseases suggesting that complement may serve as a new diagnostic and therapeutic target for both disorders.

Murine complement deficiency ameliorates acute cigarette smoke-induced nasal damage

OBJECTIVE

Exposure to cigarette smoke is a risk factor for chronic rhinosinusitis. Current literature confirms complement fragments are activated in human nasal mucosa. The mechanism(s) responsible for this activation is unclear. We investigated the effects of cigarette smoke on nasal mucosa in vitro and via a model of cigarette smoke exposure by using animals deficient in complement components.

STUDY DESIGN

Prospective, controlled animal and in vitro human cell line study.

SETTING

University laboratory.

SUBJECTS AND METHODS

Human respiratory epithelial cells were exposed to five, 10, and 20 percent cigarette smoke extract (CSE) in vitro in the presence or absence of human serum. Complement activation was assessed by enzyme-linked immunosorbent assay and immunofluorescent techniques. Complement-deficient (C3(-/-), n = 6; factor B(-/-), n = 50) and sufficient mice (wild type, n = 10) were exposed to the smoke of four cigarettes per exposure for two exposures per day for three days. Mice were sacrificed 12 hours after the last exposure, and the nasal cavity was surgically removed. Histological characteristics were analyzed by the use of a subjective scale and quantitative image analysis scoring systems.

RESULTS

In vitro analysis of respiratory cell cultures demonstrated that exposure of serum to CSE resulted in complement activation. Furthermore, immunofluorescent staining for C3d could only be demonstrated in CSE-exposed cultures. In vivo analysis demonstrated that complement deficiency, either C3 or factor B deficiency, resulted in a significant reduction in histological evidence of damage as compared with wild-type control mice (wild type vs C3(-/-), P = 0.02; wild type vs factor B(-/-), P = 0.07; no significant difference between C3(-/-) vs factor B(-/-)).

CONCLUSION

These data demonstrate that cigarette smoke activates the complement system. Furthermore, complement deficiency protected against smoke-induced mucosal damage in this small series.