Fibronectin-cleaving activity in bronchial secretions of patients with cystic fibrosis

In cystic fibrosis, colonization of the airways with Pseudomonas aeruginosa follows colonization with Staphylococcus aureus and is related to accelerated deterioration of pulmonary function. Because P. aeruginosa adheres better to cell surfaces devoid of fibronectin, we searched for fibronectin-cleaving activity in bronchial secretions and saliva from 24 patients with cystic fibrosis who were followed up for 4.5 y and from two control groups. Proteolytic activity against 125I-labeled fibronectin was continuously present in cystic fibrosis bronchial secretions; significantly higher fibronectin-cleaving activity was found in older vs. younger patients, in patients with advanced disease stages determined by a five-stage scoring system, and in those colonized with P. aeruginosa. The fibronectin-cleaving activity was due to neutrophil elastase and cathepsin G. Cystic fibrosis bronchial secretions had proteolytic activity against surface fibronectin of airway mucosal cells. Thus fibronectin-cleaving activity of bronchial secretions rather than of saliva may favor P. aeruginosa colonization of the upper respiratory tract in individuals with cystic fibrosis.     

Proteolytic inactivation of alpha 1-proteinase inhibitor in infected bronchial secretions from patients with cystic fibrosis

The chronic, progressively destructive bronchitis of patients with cystic fibrosis (CF) is characterized by an important imbalance between tissue destroying granulocyte proteases such as granulocyte elastase (GE) and its physiological inhibitors in bronchial secretions. Recent in vitro studies suggest, that proteases derived from bacteria or endogenous proteases may contribute to inactivation of physiological inhibitors of GE. Since only trypsin-unreactive alpha 1-proteinase inhibitor (alpha 1-PI) was detected in CF bronchial secretions, we attempted to identify the mechanism of inactivation of alpha 1-PI. We found a heat stable, serine protease-like enzymatic activity capable of degrading 125I-labelled alpha 1-PI extensively in 22 infected but not in one non-infected CF bronchial secretion. In infected secretions, only degraded alpha 1-PI, which did not migrate like oxidized alpha 1-PI in tandem-crossed immunoelectrophoresis, was detectable. We conclude, that free GE in excess as well as GE bound to bronchial mucosal inhibitor may partly account for the alpha 1-PI-cleaving activity, but that other yet unknown bacterial or host serine proteases also contribute to alpha 1-PI inactivation.     

Pulmonary aspiration of sinus secretions in patients with cystic fibrosis

Background

Indirect evidence suggests that sinonasal secretions are aspirated into the lungs of patients with cystic fibrosis (CF), contributing to infection, subsequent tissue damage, and decreased lung function. Our objective is to determine whether sinonasal secretions are transferred to the lungs in patients with CF‐related sinus disease and healthy subjects, particularly in the recumbent position and during sleep.

Methods

We performed a prospective, controlled trial to detect pulmonary aspiration of radiolabeled albumin applied to the nasal mucosa of study subjects with chronic sinusitis related to CF and control subjects without sinus disease. Radioactive counts were measured in the lungs and compared to background counts in both groups after 8 hours of rest/sleep.

Results

Complete data was collected on 12 CF patients and 6 controls. Eleven patients with CF demonstrated higher lung counts than background counts. The average counts of radiolabeled albumin in the lungs of CF patients were significantly greater than background counts (p = 0.03). Controls did not demonstrate this finding (p > 0.90), with only one‐half demonstrating lung counts greater than background counts.

Conclusion

This study provides direct evidence of aspiration of sinonasal secretions into the lungs of patients with CF and healthy adults in the recumbent position. The fact that both patients and controls aspirated secretions suggests that aspiration alone does not account for the pathogenesis of lung disease in CF patients.

     

Levels of free granulocyte elastase in bronchial secretions from patients with cystic fibrosis: effect of antimicrobial treatment against Pseudomonas aeruginosa

Large amounts of free granulocyte elastase (GE), an enzyme capable of mediating airway damage, have been found in bronchial secretions of patients with cystic fibrosis who are infected with Pseudomonas aeruginosa. This finding indicates an imbalance between GE and its antiproteases, alpha 1-proteinase inhibitor (alpha 1-PI) and bronchial mucosal inhibitor (BMI), in the airways of these individuals. The effect of intravenous antimicrobial treatment against P. aeruginosa on activity and concentration of GE, BMI, and alpha 1-PI was evaluated in 30 treatment courses of 20 patients with cystic fibrosis. Although sputum volume and level of immunoreactive GE decreased and concentrations of alpha 1-PI and BMI increased significantly (P less than .05), a high level of free GE persisted. No active alpha 1-PI and BMI were detectable after treatment. High levels of GE correlated with a poor pulmonary condition (rs = .98, P less than .001). In vitro, elastolytic activity of bronchial secretions from patients with cystic fibrosis was significantly inhibited by eglin C and an oxidation-resistant variant of alpha 1-PI, both compounds currently produced by recombinant DNA technology.     

Helicobacter pylori secretes a chemotactic factor for monocytes and neutrophils.

Helicobacter pylori is associated with an inflammatory reaction in the stomach and duodenum, yet the mechanism of this inflammatory infiltrate is unknown. The ability of Helicobacter pylori to secrete a factor that attracts leucocytes is investigated. Helicobacter pylori conditioned supernatant attracted neutrophils and monocytes with 50-100% of the activity of control chemotactic factor, 10(-8) M formyl-methionine-leucine-phenylalanine. Strains derived from individuals with ulcer or non-ulcer associated H pylori infections displayed similar chemotactic activity. Preliminary characterisation shows that the factor has a molecular weight of less than 3000, is heat stable, is acid resistant, and can be diluted at least 10-fold. Checkerboard analysis confirmed that the activity was chemotactic rather than chemokinetic. This chemotactic activity could play a role in the pathogenesis of Helicobacter pylori gastritis.     

Mechanisms of bronchial hyperreactivity in cystic fibrosis

We studied 14 patients with cystic fibrosis (CF) who had evidence of bronchial hyperreactivity on a standardized histamine challenge. Patients had a histamine challenge on the first day. Then they were pretreated with either 0.25 mg ipratropium bromide or 0.5 mg fenoterol hydrobromide on 2 separate days, and the histamine challenge was repeated. Baseline forced expiratory volume in 1 sec was similar on the 3 days; however, there was a small but significant (P less than 0.05) improvement after fenoterol. Mean PC20 on the control day was 1.50 mg/ml, which increased significantly after pretreatment with ipratropium (2.88 mg/ml, P less than 0.01) and fenoterol (3.64 mg/ml, P less than 0.005), indicating protection against histamine-induced bronchial hyperreactivity. The six CF patients with "coexistent asthma," as defined by recurrent episodes of wheezing responsive clinically to bronchodilator therapy, had no significant protection from ipratropium, whereas the eight "nonasthmatic" CF patients were protected by both ipratropium and fenoterol. We postulate that at least two mechanisms contribute to histamine-induced bronchial hyperreactivity in patients with CF, one related to vagally mediated reflex bronchoconstriction and another that acts independently of this mechanism.     

Self-hypnosis for patients with cystic fibrosis

This report documents the utility of self-hypnosis in patients with cystic fibrosis (CF). Sixty-three patients 7 years of age or older were offered the opportunity to be taught self-hypnosis by their pulmonologist. Forty-nine agreed to learn it. Patients generally were taught hypnosis in one or two sessions. The outcome of hypnotherapy was determined by patients' answers to open-ended questions regarding their subjective evaluation of the efficacy of hypnosis. The average age of the 49 patients who were taught and used self-hypnosis was 18.1 years (range, 7-49 years). Many of the patients used hypnosis for more than one purpose, including relaxation (61% of patients), relief of pain associated with medical procedures (31%), headache relief (16%), changing the taste of medications to make the flavor more palatable (10%), and control of other symptoms associated with CF (18%). The patients successfully utilized self-hypnosis 86% of the time. No symptoms worsened following hypnotherapy. Sixteen patients chose to practice hypnosis on their own for a half year or longer. In conclusion, with the use of self-hypnosis, patients with CF can quickly learn to enhance their control over discomforts associated with therapy and their disease. Consideration should be given to making instruction in self-hypnosis available to patients with CF.     

Platelet factor 4 is chemotactic for neutrophils and monocytes.

Platelet factor 4 is shown to be a chemotactic protein for human polymorphonuclear leukocytes and monocytes at concentrations found in human serum and reached locally in injured tissue. The maximum chemotactic response to platelet factor 4 nearly equals that achieved with saturating concentrations of the chemotactic activity derived from the fifth component of human complement, C5. Cells desensitized to C5 chemotactic activity retain chemotactic responsiveness to platelet factor 4. Serum contains inhibitory capacity against the chemotactic activity associated with platelet factor 4. Our results suggest that the local release of platelet factor 4 may be an important stimulus attracting inflammatory cells to sites of blood vessel injury.     

Lobectomy in patients with cystic fibrosis

BACKGROUND:

Some patients with cystic fibrosis (CF) develop severe but localized lung disease or recurrent hemoptysis/pneumothorax refractory to conventional medical therapies.

METHODS:

The outcomes of lung resection in patients with CF and worsening localized lung disease or recurrent hemoptysis/pneumothorax refractory to conventional therapy (n=15) were evaluated by reviewing the medical records of all patients with CF followed at the CF Center at Nationwide Children’s Hospital (Columbus, Ohio, USA), who underwent lobectomy over a 15-year period (1998 to 2012).

RESULTS:

The median age of the 15 patients (93% Caucasian) was 20 years (range two to 41 years) and their mean forced expiratory volume in 1 s (FEV₁) was 59.5% of predicted one year before surgery. Three patients died within two years after lobectomy; all three deaths occurred in patients with an FEV₁ ≤40% of predicted before surgery. There were no significant changes in mean height, weight, body mass index, hospital admissions or antibiotic use over time. The mean FEV₁ decreased over time. Compared with at surgery, decline in FEV₁ in the year before surgery was −5.4% (P=0.024) and decline in the year after surgery was −1.3% (P=0.513); however, the difference in the rate of decline was not statistically significant.

CONCLUSION:

In patients with CF and localized worsening bronchiectasis and/or recurrent hemoptysis/pneumothorax, lobectomy carried a significant risk of mortality, especially in patients with FEV₁ ≤40% of predicted, and should only be considered when all other measures fail.     

Pregnancy in patients with cystic fibrosis

As more patients with cystic fibrosis reach adulthood, questions arise about the potential hazards of pregnancy. We reviewed the medical records of eight women with cystic fibrosis who had a total of 11 completed pregnancies and had been evaluated within 1 year before conception. In five women (Group 1), the overall maternal condition was little affected by the pregnancy, and in three women (Group 2), the mother's condition deteriorated during and after pregnancy and did not return to the pregravid state. With regard to pregravid status, significant differences between patients in Group 1 and Group 2 were found in Shwachman-Kulczycki clinical scores, weight for height values, Brasfield chest radiograph scores, and pulmonary function. A quantitative assessment of pregravid nutritional and pulmonary status is useful in counseling women with cystic fibrosis about the risk of pregnancy.     

Clinical significance of the recovery of Aspergillus species from the respiratory secretions of cystic fibrosis patients

The frequent recovery of Aspergillus species from the respiratory tract secretions of cystic fibrosis (CF) patients is well recognized, and the presence of the fungus in the airways may trigger an inflammatory response that can manifest as the clinical entity known as allergic bronchopulmonary aspergillosis (ABPA). In our CF patient population we studied the clinical characteristics of those who had Aspergillus sp. recovered from their respiratory tract secretions (n = 45) and compared them with the characteristics seen, during the same time period. In those patients who were culture negative for Aspergillus sp. (n = 167). There were no differences in peripheral blood eosinophil count (P = 0.9) or serum immunoglobulin E levels (P = 0.61). By logistic regression analysis there seemed to be an increased risk for more advanced lung disease, both radiographically (defined by a Brasfield chest radiograph score <18) and by lung function parameters in those who were culture positive. However, after appropriate adjustment, almost all the increased risk was associated with age and gender, but not with the presence of Aspergillus sp. in respiratory secretions. Additionally, increasing age was strongly correlated with the risk of Aspergillus sp. being cultured from respiratory secretions (P = 0.0025). The presence of Aspergillus sp. in respiratory secretions was not associated with two indicators of atopy in our CF patient population. We do not have evidence that the culture of Aspergillus sp. from CF respiratory secretions is independently associated with an increased risk for more advanced lung disease. Pediatr Pulmonol. 1996; 21:6–10 . © 1996 Wiley-Liss, Inc.     

Inhaled tobramycin and bronchial hyperactivity in cystic fibrosis

The use of inhaled tobramycin for prophylaxis and treatment of respiratory symptoms in cystic fibrosis (CF) is now widespread. There have been concerns that inhaling the intravenous (I.V.) formulation of tobramycin causes bronchoconstriction. Previous studies using this formulation have either not specified the nebulizing equipment, or studied older, more severely affected patients. This study investigated the incidence of bronchoconstriction with tobramycin inhalation in children with mild to moderate CF. We studied 26 patients between the ages of 7 and 17 years, with mild to moderate CF (20 female). Prior to being placed on prolonged inhaled tobramycin therapy, they underwent a "tobramycin challenge." FEV(1) was measured pre and post challenge. For the test, standard I.V. solution (80 mg/2 mL) diluted with 2 mL of normal saline was nebulized, using the Hudson (Temecula, CA) RCI Updraft II nebulizer. The nebulization lasted 2 min. There was a 3-min "quiet period," following which FEV(1) was measured. A decrease in FEV(1) by at least 10% post-tobramycin inhalation was considered to be a positive test. Results were analyzed using the Pearson Chi-square test. Five of 26 (19%) had a positive reaction to tobramycin. Sixteen of 26 (61.5%) were using salbutamol on a daily basis at the time of testing but not for 48 hr before the challenge, and 16 of 26 (61.5%) had a pre-tobramycin FEV(1) of < or =80%. Neither an FEV(1) of <80% (P = 0.93) nor regular use of salbutamol (P = 0. 34) were associated with a positive tobramycin challenge. This study suggests that, while bronchoconstriction does occur, many patients do not exhibit bronchoconstriction in response to the standard I.V. preparation and, as prior work suggests, this may be reduced further by pretreatment with salbutamol.     

Chloroquine normalizes aberrant transforming growth factor beta activity in cystic fibrosis bronchial epithelial cells

Cystic fibrosis (CF) remains a fatal progressive disease in spite of the discovery and characterization of the CFTR gene. Transforming growth factor beta (TGF-beta) has been implicated in pathophysiology of CF. Previous reports have shown the trans-Golgi network (TGN) is hyperacdified in CF epithelial cells in culture and that this hyperacidification can be corrected with the membrane permeant weak base, chloroquine. In this study bioactive TGF-beta produced by CF and normal cells was measured using a reporter cell line with a TGF-beta responsive promoter linked to luciferase. Increased levels of TGF-beta were detected in the conditioned media from CF epithelial cells compared to their matched controls-(IB3-1 vs. S9; pCEP-R vs. pCEP, CuFi-4 vs. NuLi-1). Levels of TGF-beta were normalized with chloroquine indicating that the hyperacidification of the TGN of CF cells is responsible for the altered TGF-beta levels.     

Undiagnosed patients with cystic fibrosis

The missing cystics, the undiagnosed patients who have inherited cystic fibrosis (CF), have been the subject of many a question. That they exist is not to be doubted, for patients diagnosed in their 30s have been missing for 30 or more years, and even a patient diagnosed at age 1 has been missing a year. The important questions about the missing cystics are of two kinds: demographic—how many?, age distributions?, death rate?, survival rate?, proportion of all CF patients?; and clinical—does treatment alter the course of CF?, does early diagnosis make any difference?, can the diagnosis be made before the clinical syndrome is obvious?, can CF be diagnosed by screening?In this paper we will use the age at diagnosis of all new patients reported to the United States CF Patient Registry for 11 consecutive years to answer the demographic questions. Since treatment does alter the course of cystic fibrosis [1, 2], since early diagnosis improves prognosis [3], since CF can be diagnosed before the full clinical picture develops [4] and since a high risk of CF can be determined by screening tests [5], we will use our analysis to suggest a strategy for changing the answers to both the clinical and the demographic questions.     

A comparison of bronchial drainage treatments in cystic fibrosis

We compared standard chest physical therapy and postural drainage (CPT/PD) with a new airway clearance therapy called high-frequency chest wall oscillation (HFCWO) in a group of stable cystic fibrosis (CF) patients. In this crossover trial, 29 CF patients (15 males, 14 females), aged 7–47 years that met the inclusion criteria were randomly assigned to alternate CPT/PD and HFCWO, on a daily basis, over a 4 day period. Each patient received 2 days of each form of therapy; treatment frequency and the length of treatment were the same for both techniques. Expectorated secretions were collected during each 30 minute therapy session and for 15 minutes following treatment. The wet and dry weights of collected secretions were determined gravimetrically, and the therapy methods were compared. Significantly more sputum was expectorated during HFCWO than during CPT/PD as determined by both the wet (P < 0.001) and the dry (P < 0.01) measurements. This study suggests that HFCWO is at least as effective as manual CPT/PD in clearing secretions from the airways in patients with cystic fibrosis. Pediatr. Pulmonol. 1996; 22:271–274. © 1996 Wiley-Liss, Inc.