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.

Reactive oxygen species in chronic rhinosinusitis and secondhand smoke exposure.

OBJECTIVE: Reactive oxygen species (ROS) can potentiate cellular injury and inflammation. This study aimed to (1) assess the presence of reactive oxygen species in the sinus tissue of patients with chronic rhinosinusitis (CRS) and (2) assess the impact of secondhand smoke (SHS) exposure on reactive oxygen species (ROS) production. STUDY DESIGN: Retrospective cohort study. SETTING: Academic medical center. SUBJECTS AND METHODS: Sinus tissue samples from patients undergoing sinus surgery were analyzed using diaminobenzidine (DAB) staining to assess for ROS. Stained specimens were photographed at random by a blinded photographer and then quantified by 3 blinded graders. The patient's SHS exposure was determined by hair nicotine levels. RESULTS: were compared between non-smoke exposed cohorts and those exposed to secondhand smoke and by diagnosis. RESULTS: Sixty-nine adults undergoing sinus surgery were included in the study. For the non-SHS-exposed cohorts, chronic rhinosinusitis with nasal polyps (CRSwNP) had the highest number of DAB+ cells/high-powered field (hpf) followed by chronic rhinosinusitis without nasal polyps (CRSsNP) and controls. When comparing the control patients to their SHS-exposed counterparts, SHS exposure yielded statistically significantly higher levels of DAB-positive cells/hpf. SHS exposure did not affect DAB staining in CRSsNP or CRSwNP patients. CONCLUSION: ROS are differentially expressed in various subtypes of CRS. SHS exposure increases ROS in sinus tissue of control patients, but the clinical significance of this is unclear.

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.

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

BACKGROUND: The aim of this study was to determine if there is a link between local dendritic cells (DCs) and various subtypes of chronic rhinosinusitis (CRS): CRS with nasal polyposis (CRSwNP), CRS without nasal polyposis (CRSsNP), and allergic fungal rhinosinusitis (AFRS). Once DC presence was established we considered possible mechanisms for DC recruitment to the sinuses. METHODS: Biopsy specimens were taken from the osteomeatal complex during endoscopic sinus surgery in patients with AFRS (n ≥ 5), CRSsNP (n ≥ 6), and CRSwNP (n ≥ 6). Control patients (n ≥ 5) were undergoing either tumor resection or repair of cerebrospinal fluid leak and had no radiographic or endoscopic evidence of inflammatory sinus disease. Tissue samples were immunohistochemically stained for DC marker, CD209, costimulatory molecules, CD80 and CD86, and chemokine receptors, CCR2 and CCR6. Sinus tissue lysates were examined for levels of the DC chemoattractants, chemokine ligand 2 (CCL2) and CCL20. RESULTS: Analysis of sinus tissue from AFRS and CRSwNP revealed elevated numbers of cells staining positive for CD209, CD80, CD86, CCR2, and CCR6 compared to controls. CCL2 and CCL20 levels were elevated in AFRS and CRSwNP compared to controls, similar to increases in their receptors, CCR2 and CCR6, respectively. While there were trends toward increases in all markers in CRSsNP, none was statistically significant compared to control. CONCLUSION: AFRS and CRSwNP have increased numbers of DCs displaying costimulatory molecules, DC chemoattractants, and their corresponding receptors in the sinus mucosa compared to controls. These differences represent a possible mechanism for increased numbers of DCs with a T helper 2 (Th2)-skewed profile seen in CRSwNP and AFRS.

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.

Alterations in gene expression of complement components in chronic rhinosinusitis.

BACKGROUND: The complement cascade forms part of the initial innate response to pathogens in the airway. Complement activation is important in the maintenance of host homeostasis, but excessive and uncontrolled activation may lead to inflammation and disease. The role of the complement pathway in the innate response in chronic rhinosinusitis (CRS) is poorly characterized Methods: Sinus mucosa biopsy specimens from the anterior ethmoid or uncinate process of patients with allergic fungal rhinosinusitis (AFRS), CRS without NPs (CRS-NPs), and controls were harvested and gene and protein expression of C3, factor B (fB), C5, and C7 complement proteins were analyzed using quantitative polymerase chain reaction and immunohistochemical techniques. RESULTS: fB, C3, and C5 gene expression were increased in both AFRS and CRS-NPs compared with controls (p < 0.05). Transcriptional activity for the terminal pathway protein C7 was not significantly increased when compared with controls, with C7 levels actually reduced in AFRS patients when compared with controls. Immunohistochemistry studies showed the presence of C3 and fB on the mucosal surface and in submucosa of both AFRS and CRS-NPs, but not normal controls. Terminal pathway protein C9 was not found in our specimens. CONCLUSION: Both AFRS and CRS-NPs display up-regulation of the complement pathway, in particular, the alternative pathway (fB) and common pathways (C3 and C5). Enhanced innate responses as shown by alterations in complement components may play a pivotal role in the inflammatory response noted in CRS and provide potential therapeutic targets in the future.