Virginie Prulière-Escabasse

Atypical sinusitis in adults must lead to looking for cystic fibrosis and primary ciliary dyskinesia.

Hypotheses/Objectives: In adults, purulent pansinusitis or nasal polyposis starting early in life or that is permanently infected or associated either with chronic bronchial infection, infertility, or situs inversus are uncommon. In these atypical cases of chronic sinusitis (ACS), a primary dysfunction of the mucociliary clearance can be suspected. Adult patients with ACS were therefore investigated to detect primary ciliary dyskinesia (PCD) or cystic fibrosis (CF).

Otologic features in children with primary ciliary dyskinesia.

OBJECTIVES To analyze otologic features in patients with primary ciliary dyskinesia (PCD) aged 0 to 18 years and to evaluate the correlation between ultrastructural defects and severity of otologic features. DESIGN Retrospective study. SETTING Pediatric referral center. PATIENTS Fifty-eight patients with PCD were evaluated in the following 4 age intervals: group 1, preschool (≤ 5 years [n = 47]); group 2, school (6-11 years [n = 50]); group 3, teenagers (12-17 years [n = 34]); and group 4, young adults (≥ 18 years; 27 years for the oldest [n = 10]). Follow-up was 2 to 6 years in each age group; 26 patients had total follow-up of more than 12 years. Ultrastructural defects occurred in the outer dynein arm (n = 33), the inner dynein arm (n = 13), and the central complex (n = 11). One patient had typical Kartagener syndrome with typical PCD features but normal ciliary ultrastructure. MAIN OUTCOME MEASURES Frequency of acute otitis media, otitis media with effusion, otorrhea, chronic otitis media, hearing loss, and middle ear surgery and type of antibiotic regimen according to age and type of defect. RESULTS Recurrent acute otitis media decreased from group 1 (32 of 47 [68%]) to group 4 (0 of 10 [0%]) (P < .001). Otitis media with effusion was more severe in groups 1 through 3 than in group 4 (P = .02). Otorrhea decreased in group 4: 30% vs 80% (3 of 10 vs 36 of 41) in the other groups (P < .001). Half of the patients with tympanostomy tubes eventually had tympanic perforation. Hearing loss was moderate in groups 1 through 3 and mild in group 4. Continuous antibiotic therapy could be slightly reduced only in group 4. Central complex defect was a significant marker of severity for all these criteria. CONCLUSIONS Despite continuous antibiotic therapy, the middle ear condition in PCD remained severe throughout childhood, with improvement only after age 18 years. Armstrong grommet placement did not improve the middle ear condition. Central complex defect is a marker of severity.

EMMPRIN Modulates Epithelial Barrier Function through a MMP–Mediated Occludin Cleavage: Implications in Dry Eye Disease

Dry eye is a common disease that develops as a result of alteration of tear fluid, leading to osmotic stress and a perturbed epithelial barrier. Matrix metalloproteinase-9 (MMP-9) may be important in dry eye disease, as its genetic knockout conferred resistance to the epithelial disruption. We show that extracellular matrix metalloproteinase inducer (EMMPRIN; also termed CD147), an inducer of MMP expression, participates in the pathogenesis of dry eye through MMP-mediated cleavage of occludin, an important component of tight junctions. EMMPRIN expression was increased on the ocular surface of dry eye patients and correlated with those of MMP-9. High osmolarity in cell culture, mimicking dry eye conditions, increased both EMMPRIN and MMP-9 and resulted in the disruption of epithelial junctions through the cleavage of occludin. Exogenously added recombinant EMMPRIN had similar effects that were abrogated in the presence of the MMP inhibitor marimastat. Membrane occludin immunostaining was markedly increased in the apical corneal epithelium of both EMMPRIN and MMP-9 knock-out mice. Furthermore, an inverse correlation between EMMPRIN and occludin membrane staining was consistently observed both in vitro and in vivo as a function of corneal epithelial cells differentiation. These data suggest a possible role of EMMPRIN in regulating the amount of occludin at the cell surface in homeostasis beyond pathological situations such as dry eye disease, and EMMPRIN may be essential for the formation and maintenance of organized epithelial structure.

Modulation of Epithelial Sodium Channel Trafficking and Function by Sodium 4-Phenylbutyrate in Human Nasal Epithelial Cells

Sodium 4-phenylbutyrate (4-PBA) has been shown to correct the cellular trafficking of several mutant or nonmutant plasma membrane proteins such as cystic fibrosis transmembrane conductance regulator through the expression of 70-kDa heat shock proteins. The objective of the study was to determine whether 4-PBA may influence the functional expression of epithelial sodium channels (ENaC) in human nasal epithelial cells (HNEC). Using primary cultures of HNEC, we demonstrate that 4-PBA (5 mm for 6 h) markedly stimulated amiloride-sensitive sodium channel activity and that this was related to an increased abundance of α-, β-, and γ-ENaC subunits in the apical membrane. The increase in ENaC cell surface expression (i) was due to insertion of newly ENaC subunits as determined by brefeldin A experiments and (ii) was not associated with cell surface retention of ENaC subunits because endocytosis of ENaC subunits was unchanged. In addition, we find that ENaC co-immunoprecipitated with the heat shock protein constituvely expressed Hsc70, that has been reported to modulate ENaC trafficking, and that 4-PBA decreased Hsc70 protein level. Finally, we report that in cystic fibrosis HNEC obtained from two cystic fibrosis patients, 4-PBA increased functional expression of ENaC as demonstrated by the increase in amiloride-sensitive sodium transport and in α-, β-, and γ-ENaC subunit expression in the apical membrane. Our results suggest that in HNEC, 4-PBA increases the functional expression of ENaC through the insertion of new α-, β-, and γ-ENaC subunits into the apical membrane and also suggest that 4-PBA could modify ENaC trafficking by reducing Hsc70 protein expression.

Oxidative stress induces unfolding protein response and inflammation in nasal polyposis.

Nasal polyposis, a chronic inflammatory disease affecting the upper airways, is a valuable and accessible model to investigate the mechanisms underlying chronic inflammation. The main objective of this study was to investigate a potential involvement of the unfolded protein response (UPR) in the context of oxidative stress and inflammation in nasal epithelial cells from nasal polyps (NP).

A recurrent deep-intronic splicing CF mutation emphasizes the importance of mRNA studies in clinical practice.

BACKGROUND The identification by CFTR mRNA studies of a new deep-intronic splicing mutation, c.870-1113_1110delGAAT, in one patient of our series with mild CF symptoms and in three CF patients of an Italian study, led us to evaluate the mutation frequency and phenotype/genotype correlations. METHODS 266 patients with CF and related disorders and having at least one undetected mutation, were tested at the gDNA level in three French reference laboratories. RESULTS In total, the mutation was found in 13 unrelated patients (5% of those already carrying a mutation) plus 4 siblings, including one homozygote and 12 heterozygotes having a severe CF mutation. The sweat test was positive in 10/14 documented cases, the diagnosis was delayed after 20 years in 9/15 and pancreatic insufficiency was present in 5/16. CONCLUSION c.870-1113_1110delGAAT should be considered as CF-causing with phenotype variability and overall delayed diagnosis. Its frequency highlights the potential of mRNA studies.

Polypectomy compared with ethmoidectomy in the treatment of nasal polyposis.

OBJECTIVE To compare the 3-year results of 2 endoscopic surgical approaches in the management of nasal polyposis. DESIGN Retrospective medical record review. SETTING Private or institutional practice. PATIENTS A total of 127 patients with nasal polyposis were operated on by the same surgeon between January 1, 2003, and September 31, 2005. INTERVENTION The patients underwent radical ethmoidectomy (n = 77) and polypectomy (n = 50). MAIN OUTCOME MEASURES Outcome measures were global functional score, calculated by summing the scores (0-3) of each symptom (congestion, rhinorrhea, anosmia, hyperreactivity, and pain); global anatomical score (GAS), calculated by summing the score of polyp development for each nasal cavity; computed tomography score; adherence to corticosteroid therapy; oral corticosteroid consumption; and complication and subsequent operation rate. Efficacy was evaluated by comparing these data preoperatively and postoperatively (at 3 months, 1 year, and 3 years). RESULTS The global functional score and GAS were significantly improved 3 years after these techniques were performed (global functional score changes from 8.65 to 3.11 for ethmoidectomy and from 8.15 to 4.2 for polypectomy; GAS, from 5.95 to 1.83 for ethmoidectomy and from 6.57 to 3.58 for polypectomy). Congestion, pain, and GAS were improved to a significantly greater extent in the ethmoidectomy group. The subsequent operation rate for symptomatic polyp recurrence was comparable (9.1% vs 8.0%), with fewer local complications in the polypectomy group. CONCLUSION Polypectomy seems to represent a valuable alternative in the armamentarium of first-hand surgical procedures for treating nasal polyposis.

Proteomic Analysis of Nasal Epithelial Cells from Cystic Fibrosis Patients

The pathophysiology of cystic fibrosis (CF) lung disease remains incompletely understood. New explanations for the pathogenesis of CF lung disease may be discovered by studying the patterns of protein expression in cultured human nasal epithelial cells (HNEC). To that aim, we compared the level of protein expressions in primary cultures of HNEC from nasal polyps secondary to CF (CFNP, n = 4), primary nasal polyps (NP, n = 8) and control mucosa (CTRL, n = 4) using isobaric tag for relative and absolute quantification (iTRAQ) labeling coupled with liquid chromatography (LC)-MS-MS. The analysis of the data revealed 42 deregulated protein expressions in CFNP compared to NP and CTRL, suggesting that these alterations are related to CF. Overall, AmiGo analysis highlighted six major pathways important for cell functions that seem to be impaired: metabolism, G protein process, inflammation and oxidative stress response, protein folding, proteolysis and structural proteins. Among them, glucose and fatty acid metabolic pathways could be impaired in CF with nine deregulated proteins. Our proteomic study provides a reproducible set of differentially expressed proteins in airway epithelial cells from CF patients and reveals many novel deregulated proteins that could lead to further studies aiming to clarify the involvement of such proteins in CF pathophysiology.

Effect of neutrophil elastase and its inhibitor EPI-hNE4 on transepithelial sodium transport across normal and cystic fibrosis human nasal epithelial cells

BackgroundHyperactivity of the epithelial sodium (Na+) channel (ENaC) and increased Na+ absorption by airway epithelial cells leading to airway surface liquid dehydration and impaired mucociliary clearance are thought to play an important role in the pathogenesis of cystic fibrosis (CF) pulmonary disease. In airway epithelial cells, ENaC is constitutively activated by endogenous trypsin-like serine proteases such as Channel-Activating Proteases (CAPs). It was recently reported that ENaC activity could also be stimulated by apical treatment with human neutrophil elastase (hNE) in a human airway epithelial cell line, suggesting that hNE inhibition could represent a novel therapeutic approach for CF lung disease. However, whether hNE can also activate Na+ reabsorption in primary human nasal epithelial cells (HNEC) from control or CF patients is currently unknown.MethodsWe evaluated by short-circuit current (Isc) measurements the effects of hNE and EPI-hNE4, a specific hNE inhibitor, on ENaC activity in primary cultures of HNEC obtained from control (9) and CF (4) patients.ResultsNeither hNE nor EPI-hNE4 treatments did modify Isc in control and CF HNEC. Incubation with aprotinin, a Kunitz-type serine protease inhibitor that blocks the activity of endogenous CAPs, decreased Isc by 27.6% and 54% in control and CF HNEC, respectively. In control and CF HNEC pretreated with aprotinin, hNE did significantly stimulate Isc, an effect which was blocked by EPI-hNE4.ConclusionsThese results indicate that hNE does activate ENaC and transepithelial Na+ transport in both normal and CF HNEC, on condition that the activity of endogenous CAPs is first inhibited. The potent inhibitory effect of EPI-hNE4 on hNE-mediated ENaC activation observed in our experiments highlights that the use of EPI-hNE4 could be of interest to reduce ENaC hyperactivity in CF airways.

New use for an old drug: COX-independent anti-inflammatory effects of sulindac in models of cystic fibrosis.

Pulmonary disease is the main cause of morbidity and mortality in cystic fibrosis (CF) patients due to exacerbated inflammation. To date, the only anti‐inflammatory drug available to CF patients is high‐dose ibuprofen, which can slow pulmonary disease progression, but whose cyclooxygenase‐dependent digestive adverse effects limit its clinical use. Here we have tested sulindac, another non‐steroidal anti‐inflammatory drug with an undefined anti‐inflammatory effect in CF airway epithelial cells.