Cystic Fibrosis Polyps Research Articles

Cytokine profile in subjects with Cystic Fibrosis and nasal polyposis compared to patients with no nasal disorders

SummaryAlthough the cytokine profile in nasal polyposis is well documented, little is known about cytokines associated to cystic fibrosis.AimAssess the expression of cytokines IL⌝4, IL⌝5, IL⌝6, IL⌝8, GM⌝-CSF and IFN⌝-y, analyzed through RT-PCR, in the polyps of patients with cystic fibrosis.Materials and MethodsA cross-sectional, prospective study was carried out with 24 patients, 13 of whom had cystic fibrosis and nasal polyposis (Cystic Fibrosis Group) and 11 had normal otorhinolaryngological exams (Control Group). The average age was 21 years (3⌝57); 12 participants were males and 12 were females. The cytokine profile was studied in mucosal fragments (Control Group) or nasal polyps (Cystic Fibrosis Group) through RT⌝PCR. Transcriptions were studied for cytokines IL⌝4, IL⌝5, IL⌝6, IL⌝8, IFN⌝y and GM⌝CSF, adjusted for the ß⌝-actin value.ResultsInterleukins 5, 6, 8 and GM⌝CSF were similar in both groups (p>0.05). There were lower values of IFN-y⌝ (p=0.03) and a strong tendency toward an increase in IL⌝4 (p=0.06) in the Cystic Fibrosis Group.ConclusionInflammatory and structural cells may produce messenger RNA for IL⌝4, blocking the production of other cytokines such as IFN-y, suggesting the participation of this mechanism in the formation of polyps in cystic fibrosis.

Upregulation of Bcl‐2 in nasal polyps from patients with cystic fibrosis

BackgroundNasal polyps in patients with cystic fibrosis (CF) are believed to be phenotypically different than polyps affecting non‐CF patients. The aim of this study was to investigate differences in cell cycle regulatory mechanisms between these 2 groups. In this prospective study at a tertiary care academic medical center, multiple techniques were used to confirm the upregulation of antiapoptotic Bcl‐2 family proteins in CF polyps.MethodsNasal polyps were prospectively obtained from CF and non‐CF patients. The Sigma Panorama Protein Microarray for Cell Signaling was used to identify differences in protein expression between the 2 polyp groups. Western blot analysis confirmed altered expression of a subset of these proteins. Immunohistochemical staining was performed on archived tissue to further investigate B‐cell lymphoma 2 protein (Bcl‐2) expression. Following review by a pathologist, slides were digitized using an Aperio™ ScanScope XT system and staining intensity was quantified with the Positive Pixel Count algorithm. The mean staining intensity for each polyp group was compared.ResultsThe protein microarray suggested a greater than 2‐fold upregulation of Bcl‐xl in CF polyps relative to non‐CF polyps. Western blot analysis confirmed the upregulation in CF polyps of Bcl‐2, a more commonly studied protein analog of Bcl‐xl. The CF polyp group was noted to have a higher quantitative intensity of immunohistochemical staining for Bcl‐2 compared to the non‐CF group (p < 0.05).ConclusionThrough multiple modalities of protein investigation, we have demonstrated an upregulation of Bcl‐2 family proteins in CF polyps relative to polyps from non‐CF patients.

Etiology of Nasal Polyps in Cystic Fibrosis: Not a Unimodal Disease

The objective was to determine whether the polyp subtypes observed in cystic fibrosis (CF)-related sinusitis were similar to those observed in non-CF-related sinusitis. Polyp and mucus samples were collected from CF patients who presented for sinus surgery. The polyps underwent histologic and cytochemical evaluation for the presence of lymphocyte cell populations and their respective cytokine markers. The mucus samples were evaluated for DNA content. Of the polyps, 42% had an eosinophilic infiltrate, of which 80% had an additional mixed neutrophilic infiltrate. Of the remaining polyp samples, 42% did not have a granulocytic infiltrate, consistent with non-eosinophilic polyps. All samples had CD138-positive plasma cells. The mucus samples from the patients with CF showed higher extracellular DNA concentrations than did the mucus samples from patients with non-CF sinus disease. Cystic fibrosis-related polyps demonstrated an eosinophil-based dichotomy similar to that of idiopathic non-CF-related polyps. Many also demonstrated neutrophilic infiltrate, indicating that chronic mucus stasis and infection complicate the disease. Agents capable of reducing extracellular DNA may help manage sinusitis in CF patients.

Cyclooxygenase 2 and Lipoxin A4 in Nasal Polyps in Cystic Fibrosis

The etiology of nasal polyps (NPs) and sinusitis in cystic fibrosis (CF) patients is still unknown. This study investigates the presence of cyclooxygenase 2 (COX-2) and lipoxin A(4) (LXA(4)) in epithelial cultures derived from NPs and turbinates in patients with CF and without CF. NPs and turbinates were evaluated from eight CF patients with obstructing NPs undergoing sinus surgery. NPs and tissue from the hypertrophic inferior turbinate from 14 patients without history of CF undergoing sinus surgery served as control specimens. After tissue culturing, the presence of COX-2 protein and LXA(4) (ELISA) was detected in CF polyps and turbinates and compared with that of the control group. COX-2 and LXA(4) were detectable in tissue specimens of all CF patients and control patients. COX-2 was highest in CF polyps, but the difference was not significant compared with CF turbinates or polyps and turbinates of patients not suffering from CF. LXA(4), however, was significantly higher in CF NPs compared with CF turbinate tissue. Compared with NPs of patients not having CF disease, CF polyps showed markedly higher concentrations of LXA(4). LXA(4) is significantly elevated in CF NPs, whereas COX-2 is only slightly increased. The present data support the concept that LXA(4) plays an important role in CF nasal polyposis. Chronic infection in nasal polyposis and, because of inflammation, induced COX-2 in CF NPs may be related to increased LXA(4). The suspected interaction of COX-2 and LXA(4) needs further investigation.

Upregulation of RANTES in nasal polyps from patients with cystic fibrosis

Nasal polyps in patients with cystic fibrosis (CF) are believed to be phenotypically different than polyps affecting non-CF patients. The objective of this study was to characterize the expression of inflammatory cytokines within nasal polyps from CF and non-CF, aspirin-tolerant patients. "Regulated on activation, normal T-cell expressed and secreted" (RANTES) is a chemotactic cytokine involved in the recruitment and activation of eosinophils. Multiple molecular studies of non-CF polyps have established that RANTES may play an important role in nasal polyposis. Our study suggests RANTES may be upregulated in CF polyps relative to non-CF polyps. Nasal polyps were prospectively obtained from CF and non-CF, aspirin-tolerant patients. The Quantibody™ Human Cytokine Array I from RayBiotech, Inc., was used to identify differences in cytokine expression between protein extracts of two polyp groups. Four CF polyp extracts and 4 non-CF, aspirin-tolerant polyp extracts were each incubated on identical antibody subarrays, each containing 20 human cytokines in quadruplicate. Western blot analysis confirmed expression of RANTES. The protein microarray suggests a greater than 4-fold upregulation of RANTES in CF polyps relative to non-CF polyps. Western blot analysis confirmed expression of RANTES in CF polyps. Chemokines such as RANTES are responsible for the activation of inflammatory cells within the lamina propria of nasal polyps. We have demonstrated that RANTES may be an important cytokine associated with CF polyps.

Cystic fibrosis: ultrastructural changes of nasal mucosa

Cystic fibrosis (CF) is an inherited multisystemic disorder that results in a generalized dysfunction of exocrine glands. Besides chronic obstructive pulmonary diseases, chronic sinusitis, nasal polyposis and hypertrophy of the inferior turbinates with nasal airway obstruction are typical signs. Tissue samples of the inferior turbinates and nasal polyps were taken during nasal surgery from 21 children, ranging from 3 to 16 years of age. Light- and electron microscopical examination were carried out. Furthermore, specimens of nasal mucosa of patients without chronic inflammation as controls and specimens of duodenal mucosa of patients with CF were investigated. Under a thick layer of respiratory epithelium with a high proportion of goblet cells, the seromucous glands display abnormal morphological structures with wide mucous cells and cystic dilatation. The glandular cells show inhomogeneous glandular droplets in the supranuclear cell portion. The nucleus contains dispersed chromatin as a sign of increased activity and the structures of the Golgi apparatus are clearly detectable. Apart from investigations concerning nasal polyps in CF, studies on the different morphological changes of nasal mucosa at the electron microscopic level are rare. This histological study focuses on various morphological changes of nasal glands at the ultrastructural level in correlation with typical symptoms in CF. In addition, a comparison with electron microscopic findings of CF-enteropathies is proposed. These findings could help to bring information concerning new morphological aspects in the pathophysiology of patients with CF.

Mucin genes have different expression patterns in healthy and diseased upper airway mucosa

Mucus hyper-secretion is a feature of several airways diseases such as chronic rhinosinusitis, asthma, and cystic fibrosis (CF). Since mucins are major components of mucus, the knowledge of their distribution and regulation in nasal tissues is likely to improve mucus hyper-secretion therapy. The aim of this study was to evaluate and compare mucin gene expression at epithelial and glandular levels, and to identify potential mucin expression patterns for specific upper airways pathologies. Immunohistochemistry for MUC1, MUC2, and MUC4-MUC8 mucins was performed on healthy nasal mucosa (NM; n=12), bilateral nasal polyps (NP; n=38), NP from CF patients (n=10), and antrochoanal (AC) polyps (n=11). MUC2, MUC4, MUC5AC, and MUC6 mRNA expression were also analysed by in situ hybridization. MUC1, MUC4, and MUC5AC mucins were highly expressed in the epithelium and their expression pattern was similar in all NP types, MUC1 and MUC4 being increased and MUC5AC decreased compared with NM. MUC8 was highly detected at both epithelial and glandular levels with marked variability between groups. MUC5B was mainly detected in glands and the expression in all polyp types was higher than in NM. Moreover, MUC5B expression was higher in NP epithelia from CF patients than in bilateral NP and healthy NM. Although MUC2 expression was low, especially in AC polyps, it was detected in most samples. In NM, MUC6 and MUC7 were scarcely detected and MUC7 expression was restricted to glands. These results suggest that NP have a different pattern of mucin expression than healthy NM and that CF polyps (increased MUC5B) and AC polyps (decreased MUC2) have a different mucin expression pattern than bilateral NP.

Characterization of inflammatory reaction in upper airways of cystic fibrosis patients.

Inflammatory cell populations have not been yet precisely evaluated in cystic fibrosis (CF) airways. We intended to characterize morphological modifications, inflammatory cell infiltration and cell proliferation in nasal tissues obtained from 15 CF patients and from 6 non-CF patients with nasal polyposis. Morphological analysis showed an intense inflammatory infiltration in CF and non-CF tissues with only few modifications in the epithelium from CF tissues. Inflammatory cell populations characterized by specific immunolabeling were quantified, showing a predominance of macrophages and T- and B-lymphocytes and only moderate numbers of neutrophils in CF tissues; in non-CF polyps, lymphocytes and eosinophils were abundant. Proliferating cell percentages quantified after proliferating cell nuclear antigen immunolabeling were 5.3+/-4.1% (mean +/- SD) in CF polyps and 3.1+/-1.2% in non-CF polyps in epithelium but were very low in lamina propria. Intense inflammation in nasal tissues from CF patients is therefore dominated by macrophages and lymphocytes rather than by neutrophils. While morphology is preserved, proliferation is high in epithelium from CF polyps. These findings should be regarded in the future for a better understanding of inflammation in CF airway disease.

Cystic fibrosis patients with the 3272-26A-->G mutation have mild disease, leaky alternative mRNA splicing, and CFTR protein at the cell membrane.

We characterized the 3272-26A-->G mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, creating an alternative acceptor splice site in intron 17a, that competes with the normal one, although we predict from consensus values, with lower efficiency. We analyzed five Cystic Fibrosis (CF) Portuguese patients with the 3272-26A-->G/F508del genotype. Besides clinical and haplotype characterization of those patients, we report here results from CFTR transcript analysis in nasal brushings from all five patients. RT-PCR analysis supports alternative splicing in all patients and carriers, but not in controls. By sequencing, we determined that the alternative transcript includes 25 nucleotides from intron 17a, which predictively cause frameshift and a premature stop codon. The use of this alternative splice site causes a reduction in the levels of normal transcripts from the allele with this mutation and, most probably, of normal protein as well. By immunocytochemistry of both epithelial primary cell cultures and slices from CF polyps, CFTR protein is detected at the cell membrane, with three different antibodies. Ussing chamber analysis of one nasal polyp shows a high sodium absorption, characteristic of CF. Altogether, the results suggest that the main defect caused by the 3272-26A-->G mutation is a reduction in normal CFTR transcripts and protein and therefore this mutation should be included in class V, according to Zielenski and Tsui.

Flexible fiberoptic rhinoscopy in the diagnosis of nasal polyps in cystic fibrosis.

The incidence of nasal polyps in patients with CF in various studies varies from 6.7% to 48%. Fiberoptic rhinoscopy, a safe and minimally invasive diagnostic procedure, has the major advantage over routine physical examination of the nares because of the ability to examine the nose beyond the nasal vestibule. In examinations of both nostrils of 34 patients with CF age 4-30 years, nasal polyps were detected by rhinoscopic examination, but missed by physical examination in 17 (25%) of the nostrils. In 7% (5/64) of the nostrils in this series, rhinoscopy ruled out polyps that were reportedly identified on physician examination. This study confirms that even a careful physical examination of the nose is often inadequate to uncover significant nasal pathology such as nasal polyps.

Can Histologic Criteria of Nasal Polyps Be Used to Screen for Cystic Fibrosis?

Cystic fibrosis (CF) is the most common autosomal recessive disorder in Caucasians, occurring in 1 in 2,000 live births. Since the CF gene was discovered in 1985 greater than 200 gene mutations have been identified, making a population-wide screening program very costly. A high-risk group is needed for screening. Nasal polyps (NPs) occur in 20% of CF patients and chronic sinusitis in almost all patients. This study was undertaken to potentially identify individuals with mild CF by reviewing the histologic findings of nasal polyps. Three groups of nasal polyps were examined from patients with CF, patients with allergic disease, and patients with nonallergic disease and sinusitis. Polyps were stained with hematoxylin and eosin (H&E) and Alcian blue-periodic acid Schiff (AB-PAS) and examined by a pathologist. CF polyps were found to be morphologically different from non-CF polyps on H&E staining. CF nasal polyps had a thin subepithelial hyaline layer and lower eosinophil infiltrates in the polyp stroma. Objective measurements were obtained to confirm our results and findings were statistically significant. These findings suggest that nasal polyp histology may be used to identify a population of patients with mild CF for genetic screening.

Treatment and prognosis of nasal polyps in cystic fibrosis.

Nasal polyposis complicated the course of fibrosis in 157 (26%) of 605 patients. Onset before age 5 years or after age 20 years was rare. Polyposis was the initial symptom of cystic fibrosis in 13 patients. Common symptoms included obstruction to nasal air flow, mouth breathing, epistaxis, and rhinorrhea. Intranasal and oral corticosteroids and antihistamines were ineffective in preventing recurrences but did occasionally afford symptomatic relief of obstruction. Nineteen (31%) of 62 patients who never had surgery had spontaneous and permanent disappearance of polyps. Simple polypectomy was an adequate procedure for patients with substantial nasal symptoms. There were no visual complications. Other surgical complications were rare. Children and adolescents with nasal polyps should have sweat tests by pilocarpine iontophoresis to rule out cystic fibrosis.

The clinical and laboratory correlates of nasal polyps in cystic fibrosis

The clinical histories, chest X-ray appearances, skin prick test results, pulmonary function and IgE levels of 20 patients with cystic fibrosis (C.F.) complicated by nasal polyps have been compared with those of 97 C.F. controls. The patients who had developed polyps had a different clustering of symptoms to the controls with heavier birthweights, later presentations, milder gastrointestinal symptoms in infancy, less infection with Staphylococcus aureus and better vital capacities. There was no evidence on history, skin testing or IgE levels that the polyps patients were more allergic. It is likely, therefore, that nasal polyps in C.F. are due to a primary effect of the C.F. gene, although they could also be the effect of chronic nasal infection.

Nasal polyps in cystic fibrosis

In II polyps from patients with cystic fibrosis of the pancreas, the density, shape, and architecture of mucous glands were studied by the whole-mount method and compared with 102 non-cystic-fibrosis polyps. There were no differences in density which was in most polyps less than 0.5 gland/mm.2. The shape and architecture as well as other histological appearances of the polyp were also alike in both groups of polyps which could not be distinguished. The pathogenesis of nasal polyps in cystic fibrosis is discussed. Apparently, it is the same as that of non-cystic-fibrosis polyps.