Microbial metabolism of L-tyrosine protects against allergic airway inflammation.

The constituents of the gut microbiome are determined by the local habitat, which itself is shaped by immunological pressures, such as mucosal IgA. Using a mouse model of restricted antibody repertoire, we identified a role for antibody-microbe interactions in shaping a community of bacteria with an enhanced capacity to metabolize L-tyrosine. This model led to increased concentrations of p-cresol sulfate (PCS), which protected the host against allergic airway inflammation. PCS selectively reduced CCL20 production by airway epithelial cells due to an uncoupling of epidermal growth factor receptor (EGFR) and Toll-like receptor 4 (TLR4) signaling. Together, these data reveal a gut microbe-derived metabolite pathway that acts distally on the airway epithelium to reduce allergic airway responses, such as those underpinning asthma.

Transmaternal Helicobacter pylori exposure reduces allergic airway inflammation in offspring through regulatory T cells.

BACKGROUND: Transmaternal exposure to tobacco, microbes, nutrients, and other environmental factors shapes the fetal immune system through epigenetic processes. The gastric microbe Helicobacter pylori represents an ancestral constituent of the human microbiota that causes gastric disorders on the one hand and is inversely associated with allergies and chronic inflammatory conditions on the other. OBJECTIVE: Here we investigate the consequences of transmaternal exposure to H pylori in utero and/or during lactation for susceptibility to viral and bacterial infection, predisposition to allergic airway inflammation, and development of immune cell populations in the lungs and lymphoid organs. METHODS: We use experimental models of house dust mite- or ovalbumin-induced airway inflammation and influenza A virus or Citrobacter rodentium infection along with metagenomics analyses, multicolor flow cytometry, and bisulfite pyrosequencing, to study the effects of H pylori on allergy severity and immunologic and microbiome correlates thereof. RESULTS: Perinatal exposure to H pylori extract or its immunomodulator vacuolating cytotoxin confers robust protective effects against allergic airway inflammation not only in first- but also second-generation offspring but does not increase susceptibility to viral or bacterial infection. Immune correlates of allergy protection include skewing of regulatory over effector T cells, expansion of regulatory T-cell subsets expressing CXCR3 or retinoic acid-related orphan receptor γt, and demethylation of the forkhead box P3 (FOXP3) locus. The composition and diversity of the gastrointestinal microbiota is measurably affected by perinatal H pylori exposure. CONCLUSION: We conclude that exposure to H pylori has consequences not only for the carrier but also for subsequent generations that can be exploited for interventional purposes.

Predicting revision sinus surgery in allergic fungal and eosinophilic mucin chronic rhinosinusitis.

BACKGROUND: Chronic rhinosinusitis consists of several disease processes. Eosinophilic mucin is found in the subtypes of allergic fungal sinusitis (AFS) and eosinophilic mucin chronic rhinosinusitis (EMCRS). These entities frequently require surgical intervention and have high recurrence rates. OBJECTIVE: We aimed to determine factors in patients with AFS and EMCRS that may be associated with a higher rate of revision surgeries. Our hypothesis is that patients who have polyps, high Lund-Mackay score (LMS), and fungus may have higher revision rates. STUDY DESIGN: Retrospective cohort study. METHODS: This is a retrospective analysis of 117 patients identified over a 5-year period (2005-2009) with the diagnosis of AFS or EMCRS. Contingency tables were created to obtain the odds ratios estimates, and 95% confidence intervals were used to access the association between the outcome (having revision surgery or not) and other clinical binary predictors. RESULTS: Twenty-six of 117 (22%) of the study patients underwent revision surgery. Within the 2-year follow-up period, an additional five of 26 (19%) required another revision surgery. Average LMS was slightly higher in those who underwent revision surgery (16 vs. 13) on a scale of 0 to 24, with an overall mean score of 18 and standard deviation of 6.82 for the whole sample (117). Other factors evaluated were the presence of fungus, polyps, eosinophilic mucin, and the eosinophilic count and medical therapy received. CONCLUSION: The presence of eosinophilic mucin was significantly associated a higher rate of revision surgery. LEVEL OF EVIDENCE: 4. Laryngoscope, 127:59-63, 2017.

Dietary Fiber Intake Regulates Intestinal Microflora and Inhibits Ovalbumin-Induced Allergic Airway Inflammation in a Mouse Model.

BACKGROUND: Recently, academic studies suggest that global growth of airway allergic disease has a close association with dietary changes including reduced consumption of fiber. Therefore, appropriate dietary fiber supplementation might be potential to prevent airway allergic disease (AAD). OBJECTIVE: We investigated whether dietary fiber intake suppressed the induction of AAD and tried to elucidate the possible underlying mechanisms. METHODS: The control mice and AAD model mice fed with 4% standard-fiber chow, while low-fiber group of mice fed with a 1.75% low-fiber chow. The two fiber-intervened groups including mice, apart from a standard-fiber diet, were also intragastric (i.g.) administrated daily with poorly fermentable cellulose or readily fermentable pectin (0.4% of daily body weight), respectively. All animals except normal mice were sensitized and challenged with ovalbumin (OVA) to induce airway allergic inflammation. Hallmarks of AAD were examined by histological analysis and ELISA. The variation in intestinal bacterial composition was assessed by qualitative analysis of 16S ribosomal DNA (rDNA) content in fecal samples using real-time PCR. RESULTS: Low-fiber diet aggravated inflammatory response in ovalbumin-induced allergic mice, whereas dietary fiber intake significantly suppressed the allergic responses, attenuated allergic symptoms of nasal rubbing and sneezing, decreased the pathology of eosinophil infiltration and goblet cell metaplasia in the nasal mucosa and lung, inhibited serum OVA-specific IgE levels, and lowered the levels of Th2 cytokines in NALF and BALF, but, increased Th1 (IFN-γ) cytokines. Additionally, dietary fiber intake also increased the proportion of Bacteroidetes and Actinobacteria, and decreased Firmicutes and Proteobacteria. Levels of probiotic bacteria, such as Lactobacillus and Bifidobacterium, were upgraded significantly. CONCLUSION: Long-term deficiency of dietary fiber intake increases the susceptibility to AAD, whereas proper fiber supplementation promotes effectively the balance of Th1/Th2 immunity and then attenuates allergic inflammatory responses significantly, as well as optimizes the structure of intestinal microbiota, which suggests potential for novel preventive and therapeutic intervention.

Aerially transmitted human fungal pathogens: what can we learn from metagenomics and comparative genomics?

In the last few decades, aerially transmitted human fungal pathogens have been increasingly recognized to impact the clinical course of chronic pulmonary diseases, such as asthma, cystic fibrosis or chronic obstructive pulmonary disease. Thanks to recent development of culture-free high-throughput sequencing methods, the metagenomic approaches are now appropriate to detect, identify and even quantify prokaryotic or eukaryotic microorganism communities inhabiting human respiratory tract and to access the complexity of even low-burden microbe communities that are likely to play a role in chronic pulmonary diseases. In this review, we explore how metagenomics and comparative genomics studies can alleviate fungal culture bottlenecks, improve our knowledge about fungal biology, lift the veil on cross-talks between host lung and fungal microbiota, and gain insights into the pathogenic impact of these aerially transmitted fungi that affect human beings. We reviewed metagenomic studies and comparative genomic analyses of carefully chosen microorganisms, and confirmed the usefulness of such approaches to better delineate biology and pathogenesis of aerially transmitted human fungal pathogens. Efforts to generate and efficiently analyze the enormous amount of data produced by such novel approaches have to be pursued, and will potentially provide the patients suffering from chronic pulmonary diseases with a better management. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012).

[To investigate the relationship of airborne fungi and allergic disease of respiration system in the city of Wuhan region].

OBJECTIVE: To investigate the relationship between the prevalent species and the seasonal drift law of airborne fungi and respiratory allergic disease in the city of Wuhan. METHOD: Airborne fungi was investigated by exposed sides from 2007 to 2008, and 1674 patients with respiratory allergic disease that were used to do allergens skin test simultaneously, in order to analyze the simultaneous. RESULT: Airborne fungi could be detected in air all over the year. In 2007, the exposed films collected 26 734 fungi spores, and 686 other fungi (hypha and not well known fungi), to the sum of 27420. Otherwise, in 2008, the exposed films collected 26 531 fungi spores, and 730 other fungi, to the sum of 27 261. In the survey, 17 types of species of the collected fungi spores were identified, and the predominant species were alternaria sp, ustilaginales, deightoniella sp, uredinales, and the quantity of Fungi alternaria was most of all . And the peak period mainly concentrated from April to June, and from September to October. Otherwise, the positive rate of fungi skin test in patients with respiratory allergic disease was 10.48% in 2007, but 10.07% in 2008. The main period of onset of respiratory allergic disease was from April to June, and from September to October, similar as the seasonal drift law of airborne fungi. CONCLUSION: The period of onset of respiratory allergic disease was consistent with the seasonal drift law of airborne fungi.

Actinobacteria in indoor environments: exposures and respiratory health effects.

Actinobacteria are a large group of Gram-positive bacteria common in the environment, especially in the soil. They are morphologically diverse and extremely versatile in their metabolic activities. They produce tens of thousands of secondary metabolites with different biological activities. Exposure to actinobacteria in indoor environments is probably continuous, since they are both common environmental bacteria and human normal flora. However, the occurrence of some species of spore-forming filamentous actinomycetes has been associated with abnormal and health-hazardous situations, such as moisture damage of the building. The measured concentrations of actinobacteria indoors are low. Higher concentrations have been reported during the remediation work of moisture damaged buildings and in agricultural environments. Exposure to high concentrations of actinobacteria can cause allergic alveolitis. Other respiratory disorders have been reported, too and although the measured concentrations are low, the indoor exposure is always a mixture of many different agents, which may have synergistic effects. In vitro and in vivo studies have shown that actinobacteria are very immunoactive and hence, potential causative agents for respiratory and other disorders.

Detection of Staphylococcus aureus in nasal tissue with peptide nucleic acid-fluorescence in situ hybridization.

BACKGROUND: Staphylococcus aureus (SA) in the nose can be a simple colonizer but also may create an intramucosal reservoir causing recurrent infections or can be a specific immune modulator through superantigenic mechanisms. Because the colonization rate of SA is high, but immunologic reactions causing chronic disease are less frequent, the purpose of this study was to identify the presence of intramucosal SA in healthy subjects and in patients with chronic rhinosinusitis (CRS) and to eventually relate those to the specific immunologic changes due to SA enterotoxins. METHODS: Nasal tissue was collected in 40 subjects (9 controls, 21 CRS patients with [CRSwNP], and 10 CRS patients without nasal polyps [CRSsNP]). Tissues were homogenized, and mediators and specific IgE-antibodies against SA enterotoxins (SAE-IgE) were measured using the UniCAP system. The tissue was analyzed for the presence of SA by the peptide nucleic acid-fluorescence in situ hybridization (PNA-FISH) technique (AdvanDx), and a semiquantitative scoring system was applied. Mann-Whitney exact test was used for statistical analysis. RESULTS: SA in the mucosal tissue was detected in a higher quantity among CRSwNP subjects with aspirin exacerbated respiratory disease (AERD) versus controls and CRSsNP (p=0.03). Among CRSwNP patients, Th2 markers (eosinophil cationic protein, p=0.006, and total IgE, p=0.004) were increased related to the SAE-IgE status but not related to the presence of SA in the tissue. CONCLUSION: This study describes the detection of SA within nasal tissue using the PNA-FISH technique. The presence of SA in the submucosa did not correlate with the amplification of the Th2-related inflammation typically found in CRSwNP patients, but this reaction is dependent on the formation of SAE-IgE within mucosal tissue. We also show, for the first time, that submucosal SA is a prevalent finding in CRSwNP patients with AERD.

[Fungal allergy in chronic rhinosinusitis with or without polyps]. / Polipli veya polipsiz kronik rinosinüzitli olgularda mantar alerjisi.

OBJECTIVES: Fungi, by systemic or local allergic effect, may play a role in the pathogenesis of chronic rhinosinusitis (CRS). We investigated the incidence of fungal allergy in patients with CRS and its effect on the clinical characteristics of the disease. PATIENTS AND METHODS: The study included 127 patients, aged 18 years or over, with CRS (42 females, 85 males; mean age 43+/-12 years; range 19 to 78 years). Fungal allergy was determined by skin prick test and its effect was analyzed on blood eosinophil and total immunoglobulin E levels, the presence of polyps, and paranasal sinus computed tomography scores. RESULTS: Eighty-five patients (66.9%) were found to have allergy. The incidence of allergy did not differ between patients with and without polyps (p>0.05). House dust mites (62.2%) were the most frequent allergens. The incidence of fungal allergy was 38.8% in allergic patients. Isolated fungal allergy was detected in two patients (1.6%). The most frequent fungal allergens were Aspergillus, followed by Alternaria, and Penicillium. No association was found between fungal allergy and blood eosinophil and total immunoglobulin E levels, presence of polyps, or paranasal sinus computed tomography scores (p>0.05). CONCLUSION: The incidence of fungal allergy in patients with CRS was found to be high in this study. Tissue culture studies are required to determine the definitive relationship between fungal allergy and clinical features of CRS.

[Value of CT in allergic fungal sinusitis (AFS)]. / Intérêt de la tomodensitométrie dans la sinusite fongique allergique (SFA).

PURPOSE: To assess the value of CT for diagnosis and follow-up of AFS. Evaluation of characteristic CT features of AFS. METHODS: Retrospective review of 12 cases of AFS presenting with all published diagnostic criteria (1) chronic rhinosinusitis refractory to standard management (2) CT features of chronic sinusitis (3) anatomopathologic, immunoallergologic, biochemical and mycologic criteria. CT findings were correlated with surgical findings and reviewed by one ENT and two radiologists to assess the diagnostic value of different CT features, alone or in association. RESULTS: AFS was isolated in 6 cases, and associated with allergic bronchopulmonary aspergillosis (ABPA) in 6 cases. CT showed pan- or polysinusitis, unilateral or bilateral, with mucosal thickening, sinus opacification frequently heterogeneous, bony changes, fluid trapping, and with pseudotumoral appearance in 3 cases. CONCLUSION: CT findings alone are not specific or pathognomonic but may suggest AFS in the correct clinical or immunoallergologic setting. It may alert the physician to the need for complementary work-up, exclude the presence of associated lung disease, and better adapt treatment and follow-up.

Respiratory inflammatory responses among occupants of a water-damaged office building.

UNLABELLED: The National Institute for Occupational Safety and Health (NIOSH) received a request for evaluation of a water-damaged office building which housed approximately 1300 employees. Workers reported respiratory conditions that they perceived to be building related. We hypothesized that these symptoms were associated with airways inflammation. To test this hypothesis, we assessed airways inflammation in employees using exhaled breath condensate (EBC) and the fraction of exhaled nitric oxide (FENO). In September 2001, a health questionnaire was offered to all employees. Based on this questionnaire, NIOSH invited 356 symptomatic and asymptomatic employees to participate in a medical survey. In June 2002, these employees were offered questionnaire, spirometry, methacholine challenge test, allergen skin prick testing, EBC and FENO. FENO or EBC were completed by 239 participants. As smoking is highly related to the measurements that we used in this study, we included only the 207 current non-smokers in the analyses. EBC interleukin-8 (IL-8) levels, but not nitrite, were significantly higher among workers with respiratory symptoms and in the physician-diagnosed asthmatic group. Of the analyses assessed, EBC IL-8 showed the most significant relationship with a number of symptoms and physician-diagnosed asthma. PRACTICAL IMPLICATIONS: Implementation of exhaled breath condensate and exhaled nitric oxide in indoor air quality problems.

Advances in management of paranasal sinus aspergillosis.

Surgery remains the treatment of choice for mycetoma of the paranasal sinuses. Itraconazole has a useful role in reducing both the amount of surgery required and the amount of peri-operative bleeding in allergic aspergillosis, and continuing its use post-operatively for six weeks appears to reduce the recurrence rate (although a case-control study is required to validate this observation). In chronic invasive aspergillosis, itraconazole alone appears to be curative, although liver function tests should be monitored and other interactions considered. Imaging is required to monitor resolution; remineralisation occurs after approximately six months. In fulminant aspergillosis, radical surgery and amphotericin B continue to be the treatments of choice. This review discusses the management of aspergillosis of the paranasal sinuses, and in particular the role of itraconazole antifungal therapy.

Effectiveness of itraconazole in the management of refractory allergic fungal rhinosinusitis.

OBJECTIVES: Conventional management of allergic fungal rhinosinusitis (AFRS) after surgery consists of the use of steroids to immunomodulate the body's response to fungi. However, there are many side effects to prolonged steroid use, and some patients are unresponsive to standard treatment. The role of systemic antifungal drugs in AFRS is still largely unknown. This was a pilot study to evaluate the effectiveness of itraconazole, an oral antifungal drug, in the treatment of refractory AFRS. METHOD: Thirty-two patients with AFRS who had had surgery and were refractory to prednisone, steroid, and amphotericin B nasal sprays were treated with itraconazole for at least 3 months. They were evaluated with pre- and posttreatment endoscopic examinations, serum immunoglobulin E (IgE), and the 31-Item Rhinosinusitis Outcome Measure (RSOM-31) questionnaires. Monthly liver function tests were done to monitor for the hepatic side effects of itraconazole. RESULTS: Twelve cases had endoscopic improvement. Fifteen had no difference, and five had a worse endoscopic stage after 3 months. One patient had to stop treatment due to abnormal liver function tests. The mean pre- and posttreatment IgE levels were 581 microg/L and 766 microg/L, respectively. Subjectively, 9 patients (28%) reported a significant improvement, 9 (28%) had moderate improvements, and 14 (44%) reported little or no change. There was no correlation between the subjective and the endoscopic changes. CONCLUSION: Itraconazole may be useful as an adjunct in the management of AFRS. However, more studies, including a prospective randomized clinical trial, are required to determine if itraconazole is effective in the management of AFRS.

[Nasal fungal microbiota in allergic and healthy subjects]. / Microbiota fúngica nasal en sujetos alérgicos y sanos.

Environmental fungi, moulds and yeasts could reach the nasal cavity with the inhaled air causing respiratory symptoms in atopic subjects, but little is known about the fungal flora of this site. In the present study samples of the nasal cavities of 135 subjects aged 18-35 years (48 allergic patients to fungi, mites and/or cat fur and from 87 normal subjects--healthy, control group) were cultured. All of them lived in the metropolitan area of Barcelona. Fungi were isolated from 41.5% of healthy people and in 14.8% of allergy patients (p = 0.011). Morphologically, 50.4% of the isolates were located within 4 genera: Cladosporium, Penicillium, Aspergillus and Alternaria, fungi which are considered the most allergenic. The most prevalent species were: Cladosporium herbarum and C. cladosporioides (23.6%). Alternaria alternata was isolated only in 8.8% of samples from the allergic group, although most subjects were sensitive to this species. There were not differences in the isolation rate between genera and smoking-no-smoking groups. The lower prevalence of nasal fungi from allergic patients could be related to the nasal insufficiency, the hypersecretion and the larger use of handkerchiefs.

Role of granulocyte macrophage colony-stimulating factor in host defense against pulmonary Cryptococcus neoformans infection during murine allergic bronchopulmonary mycosis.

We investigated the role of granulocyte macrophage colony-stimulating factor (GM-CSF) in host defense in a murine model of pulmonary cryptococcosis induced by intratracheal inoculation of Cryptococcus neoformans. Pulmonary C. neoformans infection of C57BL/6 mice is an established model of an allergic bronchopulmonary mycosis. Our objective was to determine whether GM-CSF regulates the pulmonary Th2 immune response in C. neoformans-infected C57BL/6 mice. Long-term pulmonary fungistasis was lost in GM-CSF knockout (GM(-/-)) mice, resulting in increased pulmonary burden of fungi between weeks 3 and 5. GM-CSF was required for the early influx of macrophages and CD4 and CD8 T cells into the lungs but was not required later in the infection. Lack of GM-CSF also resulted in reduced eosinophil recruitment and delayed recruitment of mononuclear cells into the airspace. Macrophages from GM(+/+) mice showed numerous hallmarks of alternatively activated macrophages: higher numbers of intracellular cryptococci, YM1 crystals, and induction of CCL17. These hallmarks are absent in macrophages from GM(-/-) mice. Mucus-producing goblet cells were abundantly present within the bronchial epithelial layer in GM(+/+) mice but not in GM(-/-) mice at week 5 after infection. Production of both Th1 and Th2 cytokines was impaired in the absence of GM-CSF, consistent with both reduced C. neoformans clearance and absence of allergic lung pathology.

Fungal and endotoxin measurements in dust associated with respiratory symptoms in a water-damaged office building.

UNLABELLED: We investigated the associations of fungal and endotoxin levels in office dust with respiratory health in 888 (67% participation) occupants of a water-damaged building. We analyzed floor and chair dusts from 338 workstations for culturable fungi and endotoxin. Based on averages, we ranked each floor of the building as low, medium, or high for occupants' exposure to each of these agents. Multivariate logistic regression models for building-related symptoms included this ranking of fungi and endotoxin, age, gender, race, smoking status, and duration of occupancy. Using floor dust measures, we found significantly increased odds for lower respiratory symptoms [wheeze, chest tightness, attacks of shortness of breath, and attacks of cough: odds ratios (OR) = 1.7 (95% confidence interval (CI): 1.02-2.77) to 2.4 (95% CI: 1.29-4.59)], throat irritation [OR = 1.7, (95% CI: 1.06-2.82)], and rash/itchy skin [OR = 3.0, (95% CI: 1.47-6.19)] in the highest fungal exposure group compared to the lowest, with generally linear exposure-response relationships. Nonlinear relationships were observed for many of these symptoms and endotoxin in floor dust. Interaction models showed that endotoxin modified effects of fungi on respiratory symptoms. Our findings of exposure interactions and exposure-response relationships of fungal and endotoxin with increased risk of building-related symptoms contribute to an understanding of the role of microbial agents in building-related asthma and respiratory and systemic symptoms. PRACTICAL IMPLICATIONS: Our demonstration of exposure-response relationships between measurements of fungi and/or endotoxin in floor dusts and building-related symptoms implies that microbial agents in floor dust may be a good surrogate measure for dampness-related bioaerosol exposure, considering that measurements of microbial agents in air often fail to demonstrate the associations between exposure and health. In addition, our finding that endotoxin exposure may change the effect of fungal exposure (and vice versa) on respiratory heath suggests that exposure to both fungi and endotoxin should be assessed in epidemiological investigations examining the effect of fungal or endotoxin exposure on respiratory health in indoor environments.

Comparison of intradermal dilutional testing with the Multi-Test II applicator in testing for mold allergy.

OBJECTIVES: To compare and correlate wheal size using the Multi-Test II applicator with the endpoint obtained by intradermal dilutional testing (IDT) for common mold allergens. To validate the safety and efficacy of modified quantitative testing (MQT) for determining immunotherapy starting doses. STUDY DESIGN AND SETTING: Prospective study of 86 subjects with Multi-Test II and IDT for 6 common mold antigens. RESULTS: There was 84% concordance between IDT results and the results expected from the MQT method. When IDT and MQT results differed, the MQT algorithm predicted a safer endpoint for starting immunotherapy in all but 2 cases. CONCLUSION: The correlation between Multi-Test II and IDT is not strong enough to infer IDT endpoint from Multi-Test II results for molds. MQT is nearly as effective as formal IDT in determining endpoint. SIGNIFICANCE: MQT appears to be a safe method for determining starting doses for immunotherapy with fungal allergens.

Allergic fungal sinusitis (AFS)--earlier diagnosis and management.

AIM: To evaluate the criteria for diagnosing allergic fungal sinusitis and to maintain permanent drainage and ventilation, while preserving the integrity of mucosa. METHODS: This is a prospective study of 251 patients with chronic rhinosinusitis with or without polyposis, of whom 199 were treated surgically. Mucus sample collection, nasal secretion culture, surgical specimen handling and histological evaluation of surgical specimens are described. The management included wide local endoscopic sinus debridement, adequate sinus aeration, post-operative use of steroids and antifungal therapy. RESULTS: Fungal cultures of nasal secretions were positive in 201 (80.01 per cent) of 251 patients. Of the 199 surgical cases, fungal elements were found in 156 histological specimens (62.1 per cent). Allergic mucin was found in 182 patients (91.45 per cent). Nasal obstruction and proptosis were the commonest presentations. All pre-operative versus post-operative changes in AFS-associated complaints reached statistical significance of p < 0.001. The ethmoid sinus was commonly involved with adjacent lamina papyracea exhibiting demineralization in 26.6 per cent of cases. Intracranial extension was seen in 15 cases. Recurrence was noted in 11 cases. CONCLUSION: Comprehensive treatment with endoscopic sinus surgery, steroids and antifungal therapy is needed. AFS is readily recurrent. Long-term follow up is important.

Presence of surfactant lamellar bodies in normal and diseased sinus mucosa.

BACKGROUND: Pulmonary surfactant originates from phospholipid lamellar bodies secreted from the type II epithelial cell of the alveolus. In the lower airway, surfactant optimizes surface tension and oxygen exchange, decreases mucus viscosity and aids in mechanical elimination of inhaled pathogens. In addition to the lung, lamellar bodies have been identified in many other cell types throughout the human body. However, no prior studies have identified lamellar bodies in human sinus mucosa. OBJECTIVES: We performed ultrastructural studies to assess whether lamellar bodies are present in the human sinus in a variety of diseased and normal epithelium. METHODS: We biopsied sinus mucosa from 5 subjects, 1 each with allergic fungal sinusitis, eosinophilic mucin rhinosinusitis, cystic fibrosis, frontal sinus mucocele, and cerebrospinal fluid leak (healthy control). Mouse lung served as a positive control. Specimens were prepared using ferrocyanide-reduced osmium tetroxide and thiocarbohydrazide for fixation (R-OTO method) to avoid extraction of phospholipids during dehydration and were viewed with transmission electron microscopy. RESULTS: We identified lamellar bodies in the sinus mucosa of all patients. Additionally, preservation of mouse lung lamellar bodies confirms that the R-OTO method is a valid technique to preserve these structures. CONCLUSIONS: We describe a simpler, faster technique for identification of cellular phospholipid components than those used previously. Definitive identification of these lamellar bodies within ciliated pseudostratified epithelium of the upper airway indicates that surfactant may have a role in sinus function and pathophysiology.