Cell division rates decrease with age, providing a potential explanation for the age-dependent deceleration in cancer incidence.

A new evaluation of previously published data suggested to us that the accumulation of mutations might slow, rather than increase, as individuals age. To explain this unexpected finding, we hypothesized that normal stem cell division rates might decrease as we age. To test this hypothesis, we evaluated cell division rates in the epithelium of human colonic, duodenal, esophageal, and posterior ethmoid sinonasal tissues. In all 4 tissues, there was a significant decrease in cell division rates with age. In contrast, cell division rates did not decrease in the colon of aged mice, and only small decreases were observed in their small intestine or esophagus. These results have important implications for understanding the relationship between normal stem cells, aging, and cancer. Moreover, they provide a plausible explanation for the enigmatic age-dependent deceleration in cancer incidence in very old humans but not in mice.

Eosinophil extracellular trap formation is closely associated with disease severity in chronic rhinosinusitis regardless of nasal polyp status.

Chronic rhinosinusitis (CRS) is a heterogeneous inflammatory airway disease involving non-eosinophilic and eosinophilic phenotypes, which translate to various endotypes. Activated eosinophils and neutrophils are known to generate extracellular traps consisting of DNA and cytotoxic granule proteins. We sought to investigate the presence of eosinophil and neutrophil extracellular traps (EETs and NETs, respectively) in human CRS tissues and to clarify the associations with their clinical features. Nasal polyp (NP) or ethmoid tissue slides of 43 subjects from endoscopic sinus surgery for CRS were analysed. Quantitative analysis of EETs and NETs was performed by confocal microscopy using immunofluorescent staining. For correlation study, the presence of NPs, number of infiltrating tissue eosinophils, preoperative Lund-Mackay scores, and other comorbidities were analysed. EET formation was observed to varying degrees in all CRS groups and was correlated with the number of tissue eosinophils (r = 0.83, p < 0.001) regardless of the presence of NPs. Patients with more EETs demonstrated higher Lund-Mackay scores (r  =  0.51, p  = 0.009), blood eosinophilia (r  =  0.80, p  < 0.001), and decreased olfactory function (r  = -0.65, p  < 0.001). No correlation between the extent of EET formation and the presence of atopy or asthma was apparent. However, none of the CRS groups containing neutrophils formed NETs in this study. Eosinophilic CRS indicates the presence of EETs. Formation of EETs could have a role in clinical decision-making and prediction of treatment outcome of CRS, regardless of NP status.

Deferiprone has anti-inflammatory properties and reduces fibroblast migration in vitro.

Normal wound healing is a highly regulated and coordinated process. However, tissue injury often results in inflammation with excessive scar tissue formation after 40-70% of operations. Here, we evaluated the effect of the iron chelator deferiprone on inflammation and the migration of primary nasal fibroblasts and primary human nasal epithelial cells (HNECs) in vitro. The cytotoxicity of deferiprone was examined by the lactate dehydrogenase assay on primary nasal fibroblasts and air-liquid interface (ALI) cultures of HNECs. Wound closure was observed in scratch assays by using time-lapse confocal scanning laser microscopy. Interleukin-6 (IL-6) and type I and III collagen protein levels were determined by ELISA. Intracellular Reactive Oxygen Species (ROS) activity was measured by utilizing the fluorescent probe H2DCFDA. Deferiprone at 10 mM concentration was non-toxic to primary fibroblasts and HNECs for up to 48 hours application. Deferiprone had significant dose-dependent inhibitory effects on the migration, secreted collagen production and ROS release by primary nasal fibroblasts. Deferiprone blocked Poly (I:C)-induced IL-6 production by HNECs but did not alter their migration in scratch assays. Deferiprone has the potential to limit scar tissue formation and should be considered in future clinical applications.

Plant flavones enhance antimicrobial activity of respiratory epithelial cell secretions against Pseudomonas aeruginosa.

Flavones are a class of natural plant secondary metabolites that have anti-inflammatory and anti-bacterial effects. Some flavones also activate the T2R14 bitter taste receptor, which is expressed in motile cilia of the sinonasal epithelium and activates innate immune nitric oxide (NO) production. Flavones may thus be potential therapeutics for respiratory infections. Our objective was to examine the anti-microbial effects of flavones on the common sinonasal pathogens Candida albicans, Staphylococcus aureus, and Pseudomonas aeruginosa, evaluating both planktonic and biofilm growth. Flavones had only very low-level antibacterial activity alone. They did not reduce biofilm formation, but did reduce production of the important P. aeruginosa inflammatory mediator and ciliotoxin pyocyanin. However, flavones exhibited synergy against P. aeruginosa in the presence of antibiotics or recombinant human lysozyme. They also enhanced the efficacy of antimicrobials secreted by cultured and primary human airway cells grown at air-liquid interface. This suggests that flavones may have anti-gram-negative potential as topical therapeutics when combined with antibiotics or in the context of innate antimicrobials secreted by the respiratory or other epithelia. This may have an additive effect when combined with T2R14-activated NO production. Additional studies are necessary to understand which flavone compounds or mixtures are the most efficacious.

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.

Distribution of CGRP and TRPV2 in Human Paranasal Sinuses.

Immunohistochemistry for protein gene product 9.5 (PGP 9.5), calcitonin gene-related peptide (CGRP) and the transient receptor potential cation channel subfamily V member 2 (TRPV2) was performed on human paranasal sinuses. It was found that in the paranasal sinuses, mucous membranes contain PGP 9.5-immunoreactive (PGP 9.5-IR) nerve fibers. Such nerve fibers terminated around large blood vessels as fine varicosities. Isolated PGP 9.5-IR nerve fibers were scattered beneath the epithelium. Glandular tissues were also innervated by PGP 9.5-IR nerve fibers. These fibers were numerous in the maxillary and ethmoid sinuses, and relatively rare in the frontal and sphenoid sinuses. CGRP-IR nerve fibers were common in the maxillary sinus whereas TRPV2-IR nerve fibers were abundant in the ethmoid sinus. They were located around large blood vessels in the lamina propria. Many subepithelial nerve fibers contained TRPV2 immunoreactivity in the ethmoid sinus. CGRP- and TRPV2-IR nerve fibers were very infrequent in the frontal and sphenoid sinuses. In the human trigeminal ganglion (TG), sensory neurons contained CGRP or TRPV2 immunoreactivity. CGRP-IR TG neurons were more common than TRPV2-IR TG neurons. CGRP-IR TG neurons were of various cell body sizes, whereas TRPV2-IR TG neurons were mostly medium-to-large. In addition, human spinal and principal trigeminal sensory nuclei contained abundant CGRP- and TRPV2-IR varicosities. This study indicates that CGRP- and TRPV2-containing TG neurons probably innervate the paranasal sinus mucosae, and project into spinal and principal trigeminal sensory nuclei.

Eosinophil production of prostaglandin D2 in patients with aspirin-exacerbated respiratory disease.

BACKGROUND: Aspirin-exacerbated respiratory disease (AERD) differs from aspirin-tolerant disease in part because of eosinophilic tissue infiltration and overexpression of arachidonic acid metabolic pathway components that lead to enhanced secretion of cysteinyl leukotrienes and prostaglandin (PG) D2 observed constitutively and paradoxically in response to aspirin and other COX inhibitors. We have previously demonstrated the capacity of IFN-γ to drive cysteinyl leukotriene expression and response. OBJECTIVE: We investigated eosinophils as a source of PGD2 production in patients with AERD. METHODS: Eosinophils were enriched from tissue and peripheral blood obtained from control subjects, patients with aspirin-tolerant disease, and patients with AERD. mRNA was extracted and evaluated for expression of hematopoietic prostaglandin D synthase (hPGDS). Expression of hPGDS protein was confirmed with Western hybridization and immunofluorescence staining. Cells were stimulated with aspirin, and secretion of PGD2 was quantified. CD34+ progenitor cells were isolated and matured into eosinophils in the presence or absence of IFN-γ and hPGDS mRNA, and PGD2 release was measured. RESULTS: Gene expression analysis revealed that eosinophils from tissue and blood of patients with AERD display increased levels of hPGDS compared with asthmatic and control samples. Western hybridization confirmed the increase in hPGDS mRNA translated to increased protein expression. Immunofluorescence confirmed mast cells and eosinophils from tissue of patients with AERD and asthma demonstrated hPGDS expression, with higher levels in eosinophils from patients with AERD. Incubation of eosinophils from blood and tissue with aspirin stimulated PGD2 release. IFN-γ-matured eosinophil progenitors showed enhanced hPGDS expression and increased levels of PGD2 release at baseline and after aspirin stimulation. CONCLUSIONS: In addition to mast cells, eosinophils represent an important source of PGD2 in patients with AERD and identify a new target for therapeutic intervention.

Resveratrol ameliorates abnormalities of fluid and electrolyte secretion in a hypoxia-Induced model of acquired CFTR deficiency.

OBJECTIVE/HYPOTHESIS: Ineffective mucociliary clearance (MCC) is a common pathophysiologic process that underlies airway inflammation and infection. A dominant fluid and electrolyte secretory pathway in the nasal airways is governed by the cystic fibrosis transmembrane conductance regulator (CFTR). Decreased transepithelial Cl(-) transport secondary to an acquired CFTR deficiency may exacerbate respiratory epithelial dysfunction by diminishing MCC and increasing mucus viscosity. The objectives of the present study are to 1) develop a model of acquired CFTR deficiency in sinonasal epithelium using hypoxia, 2) investigate whether the polyphenol resveratrol promotes CFTR-mediated anion transport, 3) explore resveratrol mechanism of action and determine therapeutic suitability for overcoming acquired CFTR defects, and 4) test the drug in the hypoxic model of acquired CFTR deficiency in preparation for a clinical trial in human sinus disease. We hypothesize that hypoxia will induce depletion of airway surface liquid (ASL) secondary to acquired CFTR deficiency and that resveratrol will restore transepithelial Cl(-) secretion and recover ASL hydration. STUDY DESIGN: Basic science. METHODS: Murine nasal septal (MNSE) and human sinonasal epithelial (HSNE) cultures were incubated under hypoxic conditions (1% O2 , 5% CO2 ) and transepithelial ion transport (change in short-circuit current = ΔISC ) evaluated in Ussing chambers. Resveratrol was tested using primary cells and HEK293 cells expressing human CFTR by Ussing chamber and patch clamp techniques under both phosphorylating and nonphosphorylating conditions. CFTR activation was evaluated in human explants and by murine in vivo (nasal potential difference) assessment. Cellular cyclic adenosine monophosphate (cAMP) (ELISA) and subsequent CFTR regulatory domain (R-D) phosphorylation (gel-shift assay) were also evaluated. Effects of hypoxia and resveratrol on ASL were tested using confocal laser scanning microscopy (CLSM) and micro-optical coherence tomography (µOCT). RESULTS: Hypoxia significantly decreased ΔISC (in µA/cm(2) ) attributable to CFTR at 12 and 24 hours of exposure in both MNSE (13.55 ± 0.46 [12 hours]; 12.75 ± 0.07 [24 hours] vs. 19.23 ± 0.18 [control]; P < 0.05) and HSNE (19.55 ± 0.56 [12 hours]; 17.67 ± 1.13 [24 hours] vs. 25.49 ± 1.48 [control]; P < 0.05). We have shown that resveratrol (100 µM) enhanced CFTR-dependent Cl(-) secretion in HSNE to an extent comparable to the recently Food and Drug Administration-approved CFTR potentiator, ivacaftor. Cl(-) transport across human sinonasal explants (78.42 ± 1.75 vs. 1.75 ± 1.5 [control]; P < 0.05) and in vivo murine nasal epithelium (-4 ± 1.8 vs. -0.8 ± 1.7 mV [control]; P < 0.05) were also significantly increased by the drug. No increase in cAMP or CFTR R-D phosphorylation was detected. Inside-out patches showed increased CFTR open probability (NPo/N (N = channel number]) compared to controls in both MNSE (0.329 ± 0.116 vs. 0.119 ± 0.059 [control]; P < 0.05) and HEK293 cells (0.22 ± 0.048 vs. 0.125 ± 0.07 [control]; P < 0.05). ASL thickness was decreased under hypoxic conditions when measured by CLSM (4.19 ± 0.44 vs. 6.88 ± 0.67 [control]; P < 0.05). A 30-minute apical application of resveratrol increased ASL depth in normal epithelium (8.08 ± 1.68 vs. 6.11 ± 0.47 [control]; P < 0.05). Furthermore, hypoxia-induced abnormalities of fluid and electrolyte secretion in sinonasal epithelium were restored with resveratrol treatment (5.55 ± 0.74 vs. 3.13 ± 0.17 [control]; P < 0.05). CONCLUSIONS: CFTR activation with a leading edge Cl(-) secretagogue such as resveratrol represents an innovative approach to overcoming acquired CFTR defects in sinus and nasal airway disease. This exciting new strategy bears further testing in non-CF individuals with chronic rhinosinusitis. LEVEL OF EVIDENCE: N/A. Laryngoscope, 125:S1-S13, 2015.

Itraconazole and clarithromycin inhibit P-glycoprotein activity in primary human sinonasal epithelial cells.

BACKGROUND: Itraconazole and clarithromycin are clinically effective in the treatment of chronic rhinosinusitis (CRS) through incompletely understood anti-inflammatory properties. P-glycoprotein (P-gp) is overexpressed in CRS and inhibition results in decreased inflammatory cytokine secretion. Both itraconazole and clarithromycin have also been shown to have P-gp inhibitory properties in other tissues, suggesting a novel explanation for their immunomodulatory effects in CRS. The purpose of this study is to therefore confirm whether these drugs are capable of inhibiting P-gp specifically in sinonasal epithelial cells. METHODS: This was an institutional review board (IRB)-approved study in which primary sinonasal epithelial cells were cultured in 96-well plates. A Calcein AM assay was used to quantify P-gp inhibition as determined by an increase in intracellular fluorescence. A dose-response curve was generated for itraconazole and clarithromycin (maximal concentration 100 µM) and compared to that of Zosuquidar, a highly specific known P-gp inhibitor. Results were compared using a Student t test with a significance defined as p < 0.05. RESULTS: Both itraconazole and clarithromycin demonstrated a dose-response curve for P-gp inhibition similar to that of Zosuquidar. The respective maximal inhibitory concentrations of Zosuquidar, itraconazole, and clarithromycin prior to induction of cytotoxicity were 0.31, 3.13, and 1.56 µM, respectively, as demonstrated by a statistically significant increase in total intracellular fluorescence (p < 0.05 in all groups). CONCLUSION: Both itraconazole and clarithromycin are capable of inhibiting sinonasal epithelial cell associated P-gp. The anti-inflammatory effects of these agents in CRS may be attributable, in part, to their heretofore unrecognized P-gp modulatory properties.

Enhanced presence of NGF and mast cells number in nasal cavity after autologous stimulation: relation with sensorineural hearing deficit.

OBJECTIVE: Nerve growth factor (NGF) is a neurotrophin which promote and regulate the survival of neurons in the peripheral nervous system. We aimed to evaluate the nasal NGF expressions of mast cells in healthy patients after stimulation with sterilized isotonic solution delivered at high pressure. PATIENTS AND METHODS: The first part of the study was made with 21 voluntary individuals. The middle third of the inferior turbinate epithelial cells on the right nostril was scraped using a sterile curette and indicated as (pre), than a spray of sterilized isotonic solution at high pressure on the left nostril was delivered and 25 minutes later a similar stimulation was delivered on the same nostril. The stimulation was made with a specific spray. The middle third of the inferior turbinate epithelial cells on the left nostril was scraped using a sterile curette and indicated as (post). RESULTS: Forced nasal stress induced by local delivery of high pressure physiological solution causes an increase in the number of mast cells and enhances level of NGF in the nasal fluid compared to the control subjects. So based on the first part of our study, since NGF is universally known as effective in protection and repairing of neural cells damage, we started the second part and gave a treatment on the same patients, to increase NGF levels with a six months daily therapy and observed the variations in Sensorineural Hearing Loss (SNHL) and tinnitus intensity from the beginning to the end of the therapy. All patients received sterilized isotonic solution at high pressure (pression emission level: PEL): 7 g/sec for 0.5 sec (emission time: ET) in both nostrils. 25 minutes later a similar stimulation was delivered twice a day. The control group (21 pts) received normal therapy with betahistine dihydrochloride 16 mg twice a day. CONCLUSIONS: Upon acuphenometry, there was a lower intensity of tinnitus and the improvement was signaled by the patients. Patients with SNHL treated with conventional therapy had a slight worsening, while the patients treated with our new therapy which increased NGF levels, showed improvement of hearing. This new therapy represents a new therapy of SNHL, tinnitus and hearing disorders.

Ethmoid roof radiology; analysis of lateral lamella of cribriform plate.

OBJECTIVE: We evaluated the extent of asymmetry evident in paranasal sinus computed tomography (CT) scans of Turkish patients without sinusitis in the ethmoid roof. Our data contribute to the body of knowledge on the subject. MATERIALS AND METHODS: We retrospectively studied multiplanar reformatted CT images of the paranasal sinus (1-mm sections) from 110 patients (50 male, 60 female). Ethmoid roof variations on either side were compared and the lateral lamellar length of the cribriform plate was measured. The results were scored using the Keros classification. RESULTS: The lateral lamella of the cribriform plate averaged 5.78 mm in height on the right side and 5.98 mm on the left. The most common Keros type was type 2 (67.72%), followed by type 3 (22.28%), and type 1 (10%). Keros asymmetry (≥ 0.01 mm, affecting either side) was apparent in all patients (48.2% right-sided and 51.8% left-sided). RESULTS: Preoperatively, paranasal sinus CT scans should be evaluated carefully to eliminate the possibility of life-threatening complications, including intracranial trauma, which may develop during endoscopic sinus surgery; the left and right sides of the ethmoid roof may differ in depth.

In vitro studies of a distillate of rectified essential oils on sinonasal components of mucociliary clearance.

BACKGROUND: Herbal remedies predate written history and continue to be used frequently for many common ailments. The essential oil mixture standardized is a phytopharmaceutical with a distillate of a mixture of rectified essential oils of eucalyptus, sweet orange, myrtle, and lemon as active ingredients used to treat respiratory diseases such as bronchitis and rhinosinusitis. We evaluated the pharmacologic effects of a distillate of rectified essential oils standardized on primary human upper respiratory epithelial cultures specifically addressing electrolyte transport, cilia beat frequency (CBF), airway surface liquid (ASL) hydration, and mucus transport velocity. METHODS: Well-differentiated primary human sinonasal epithelial cultures grown at an air-liquid interface were treated on the apical or basolateral surface with varying concentrations of a distillate of rectified essential oils standardized. Changes in CBF were determined using the Sissons-Ammons Video Analysis system while changes in chloride flux were determined using the fluorescent dye 6-methoxy-N-(3-sulfopropyl)quinolinium. ASL hydration was quantified using Texas red dextran and mucociliary transport velocity was measured using fluorescent microspheres and time lapse photography. RESULTS: When applied to the basolateral surface, a distillate of rectified essential oils standardized activated chloride efflux and ciliary beat in a dose-dependent fashion, increasing ASL height and accelerating mucociliary transport velocity. The ancillary apical application of a distillate of rectified essential oils standardized had minimal effects on the CBF. CONCLUSION: Basolateral application of a distillate of rectified essential oils standardized stimulates both chloride efflux and cilia beat frequency resulting in a synergistic effect dramatically augmenting mucociliary transport velocity. These in vitro data support the clinical efficacy of this phytopharmaceutical in respiratory inflammatory disorders.

Effects of thymoquinone and montelukast on sinonasal ciliary beat frequency.

BACKGROUND: Herbal remedies predate written history and continue to be used more frequently than conventional pharmaceutical medications. Thymoquinone (TQ) is a traditional herb that has been used for its anti-inflammatory, antioxidant, and chemopreventive effects. Montelukast is a conventional medication used to treat allergic rhinitis and asthma. The aim of this research was to evaluate the effects of TQ and montelukast on human respiratory epithelium specifically addressing effects on cilia beat frequency (CBF). METHODS: Well-differentiated human sinonasal epithelial cultures, grown at an air-liquid interface were treated with varying concentrations of TQ and montelukast. Changes in CBF were determined using the Sissons-Ammons Video Analysis system. RESULTS: When applied to the basolateral surface, TQ showed a statistically significant dose-dependent increase in CBF with maximal stimulation at 30 minutes. Effects of montelukast on CBF showed both time and dose dependence with maximal stimulatory effect measured at 6 hours. CONCLUSION: The results of our study indicate that TQ and montelukast have dose-dependent effects on CBF, extending their mechanism of action in respiratory diseases.

S-100 protein-positive mast cells in canine paranal sinus (Sinus paranalis).

The aim of this study was to establish the immunocytochemical expression of S-100 protein in mast cells, localized in the wall of dog's paranal sinus. Control serial sections were used for immunocytochemical detection of tryptase-positive mast cells. It was observed that S-100-positive cells have the same morphology and localization as the tryptase-positive mast cells, which indicated that S-100-positive cells are most probably mast cells with abilities as dendritic cells. In conclusion, for the first time, the current study gave evidence that mast cells in this organ possess one more function, such as dendritic cells.

Biological characteristics and propagation of human rhinovirus-C in differentiated sinus epithelial cells.

Information about the basic biological properties of human rhinovirus-C (HRV-C) viruses is lacking due to difficulties with culturing these viruses. Our objective was to develop a cell culture system to grow HRV-C. Epithelial cells from human sinuses (HSEC) were differentiated at air-liquid interface (ALI). Differentiated cultures supported 1-2 logs growth of HRV-C15 as detected by quantitative RT-PCR. Two distinguishing features of HRVs are acid lability and optimal growth at 33-34 °C. We used this system to show that HRV-C15 is neutralized by low pH (4.5). In contrast to most HRV types, replication of HRV-C15 and HRV-C41 was similar at 34 and 37°C. The HSEC ALI provides a useful tool for quantitative studies of HRV-C replication. The ability of HRV-C to grow equally well at 34°C and 37°C may contribute to the propensity for HRV-C to cause lower airway illnesses in infants and children with asthma.

Safety evaluation of sinus surfactant solution on respiratory cilia function.

BACKGROUND: A common complaint of chronic rhinosinusitis (CRS) is thickened inspissated nasal secretions and concomitant postnasal drip. Recently, the use of diluted, baby shampoo demonstrated modest improvement in these complaints. Removal of hair-specific ingredients, such as thickeners and fragrances, and addition of a humectant and optimization of mucoactive ingredients generated a topical surfactant solution designed for sinonasal use. This study evaluates the safety of this solution on respiratory cilia function. METHODS: Murine nasal explants as well as murine nasal air-liquid interface cultures were tested. Using high-speed video microscopy, baseline ciliary beat frequency (CBF) was established, followed by addition of the surfactant solution. CBF was recorded every 30 seconds for 15 minutes. RESULTS: Sinonasal surfactant solution diluted in bicarbonate buffered saline resulted in a transient increase of CBF in murine explants and mature epithelial cultures with no evidence of toxicity on respiratory cilia over the 15 minutes. CONCLUSION: Respiratory mucosal explants and air-liquid interface cultures demonstrate robust ciliary beating and represent 2 model systems for screening topical agents for ciliotoxicity. In both systems, application of a novel sinonasal surfactant solution diluted in bicarbonate buffered saline was not ciliotoxic to respiratory epithelium over a 15-minute period.

Dual nature of T cell-epithelium interaction in chronic rhinosinusitis.

BACKGROUND: T-cell infiltration of submucosa, release of proinflammatory cytokines leading to epithelial activation, and contributions to inflammation are observed in chronic rhinosinusitis (CRS). OBJECTIVES: Molecular mechanisms and kinetics of T-cell interaction with sinus epithelium leading to activation followed by subsequent apoptosis of epithelial cells were the focus of the current study. METHODS: Primary human sinus epithelial cells and T cells generated from sinus tissues of healthy individuals and patients with CRS with or without allergy and sinus tissue biopsies were characterized in terms of activation (surface marker expression, cytokine production via real-time PCR, confocal microscopy, ELISA) and apoptosis (annexin V/7-amino-actinomycin D staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay, receptor expression by flow cytometry, confocal microscopy) of epithelial cells. RESULTS: Primary human sinus epithelial cells isolated from patients with CRS were at an activated state with upregulated expression of HLA-DR, IFN-gamma-inducible protein 10, monokine induced by IFN-gamma, and TNF-related apoptosis-inducing ligand (TRAIL) compared with healthy individuals. The expressions of these chemokines, HLA-DR, TRAIL, and TNF receptor 2 were significantly induced by IFN-gamma, whereas TRAIL receptor 4 was downregulated. Epithelial cells started to undergo apoptosis 48 hours after IFN-gamma stimulation when the transcription of proinflammatory cytokines and chemokines decreased to initial levels. The essential factors for sinus epithelial apoptosis were T(H)1 cells and IFN-gamma. Epithelial apoptosis was enhanced by Fas-Fas-ligand and TRAIL-TRAIL receptor 2 interactions. Remarkable apoptosis of epithelial cells and shedding was observed in CRS in situ. CONCLUSION: Epithelial cell interaction with activated T cells is a biphasic phenomenon in CRS. Initially activated T cells lead to activation and induction of proinflammatory functions of epithelial cells, and thereafter their apoptotic death, resulting in no more contribution to inflammation, takes place.

[Dependence of the physiological nasal cycle on the activity of mucociliary transport of paranasal sinus mucosa].

The endoscopic technique was used to manage bilateral isolated cystic sinusitis in 40 patients. Thirty two and eight patients underwent surgery on maxillary and sphenoidal sinuses respectively. Mucociliary transport in mucosal blood flow and confluence of sinuses were monitored intraoperatively. The physiological nasal cycle was fixed prior to surgery. Active mucociliary transport (MCT) was observed in maxillary and sphenoidal sinuses at the side of nasal cycle vasoconstriction. In all the patients natural anastomoses between sinuses were widely open; the patients differed in terms of the structure of osteomeatal complex and posterior cells of the ethmoidal labyrinth. Pathomorphological studies revealed pseudocysts in 90% of the patients. Envelopes of pseudocysts showed signs of chronic inflammation with immunologically governed alteration that is believed to be responsible for the large duration of the inflammatory process.

Airway reconstruction with carrier-free cell sheets composed of autologous nasal squamous epithelium.

OBJECTIVES/HYPOTHESIS: Although skin has been the most effective graft material for reconstructing the airway lumen, the use of squamous epithelium has many problems. If autologous airway squamous epithelium could differentiate into mucociliary epithelium after in vivo grafting, it could be an answer to these problems. In this study, we wanted to examine whether carrier-free nasal epithelial cell sheets composed of autologous squamous epithelium could be used as a substitute for skin in airway luminal reconstruction in three maxillectomy patients. STUDY DESIGN: In vitro biochemical experiments with in vivo applications. METHODS: We cultured nasal squamous epithelium from three maxillary cancer patients prior to maxillectomy. These squamous cell sheets were grafted on the forearm free flap, and, after maxillectomy, the surgical defect was reconstructed with a prefabricated myocutaneous radial forearm free flap with the cultured nasal squamous epithelium. At 1 and 3 month intervals after the reconstructive surgery, the cultured cell grafted area was investigated with histologic phenotype, comparing the skin grafted area. RESULTS: The autologous nasal squamous epithelial cell sheet differentiated into mucociliary epithelium without the crust or mucus stagnation that is usually observed in cases in which skin graft is used for airway reconstruction. CONCLUSIONS: We suggest that autologous cultured nasal squamous epithelium, which differentiates into mucociliary epithelium after in vivo grafting, can be used as a clinically relevant substitute for skin graft in airway luminal reconstruction.