Prevalence of Smoking and Provision of Smoking Cessation Advice during Hospitalization

Aim We aimed to determine the prevalence of smoking and smoking cessation advice received by inpatients in Beaumont Hospital and compared results to previous similar studies. Method Cross-sectional survey where we interviewed eligible in-patients over a two-week period. Results 14.8% (30/203) of participants were current smokers, which is lower than the smoking prevalence found by previous studies. The rate of cessation advice delivery was 53.3% (16/30). An increasing socioeconomic gap between smokers and non-smokers over time was found. Discussion There remains limited provision of smoking cessation advice to inpatients.

A specialized method of sputum collection and processing for therapeutic interventions in cystic fibrosis

Cystic fibrosis (CF) lung disease is characterized by aggressive neutrophil-dominated inflammation mediated in large part by neutrophil elastase (NE), an omnivorous protease released by activated or disintegrating neutrophils and a key therapeutic target. To date, several short-term studies have shown that anti-NE compounds can inhibit NE and have anti-inflammatory effects. However, progression to large-scale or multicenter clinical trials has been hampered by the fact that the current gold standard methodology of evaluating airway NE inhibition, bronchoalveolar lavage (BAL), is invasive, difficult to standardize across sites and excludes those with severe lung disease. Attempts to utilize sputum that is either spontaneously expectorated (SS) or induced (IS) have been hindered by poor reproducibility, often due to the various processing methods employed. In this study, we evaluate TEmperature-controlled Two-step Rapid Isolation of Sputum (TETRIS), a specialized method for the acquisition and processing of SS and IS. Using TETRIS, we show for the first time that NE activity and cytokine levels are comparable in BAL, SS and IS samples taken from the same people with CF (PWCF) on the same day once this protocol is used. We correlate biomarkers in TETRIS-processed IS and clinical outcome measures including FEV₁, and show stability and reproducible inhibition of NE over time in IS processed by TETRIS. The data offer a tremendous opportunity to evaluate prognosis and therapeutic interventions in CF and to study the full spectrum of people with PWCF, many of whom have been excluded from previous studies due to being unfit for BAL or unable to expectorate sputum.

Radiological abnormalities associated with Aspergillus colonization in a cystic fibrosis population

OBJECTIVE

To determine if sputum colonization with Aspergillus species in patients with cystic fibrosis (PWCF) correlates with radiological abnormalities and/or a reduction in pulmonary function (FEV1).

METHODS

We prospectively evaluated 32 PWCF utilizing high resolution computed tomography (HRCT) of the thorax and pulmonary function testing (PFT). The cohort was assessed as two groups: Aspergillus positive (n=16) and Aspergillus negative (n=16) based on sputum culture for Aspergillus species. A modified Bhalla scoring system was applied to each HRCT scan by two blinded radiologists.

RESULTS

Aspergillus positive patients had more severe and significant bronchiectasis compared to those Aspergillus negative (p<0.05). This was most marked in the right upper and lower lobes (RUL, RLL). Total Bhalla score was clinically significant in both groups and approached statistical significance between groups (p=0.063). No difference in pulmonary function between the groups was detected.

CONCLUSION

PWCF colonized by Aspergillus species have greater radiological abnormalities undetectable by PFTs. Early radiological evaluation of Aspergillus colonized PWCF is therefore warranted.

Development of predictive models for airflow obstruction in alpha-1-antitrypsin deficiency

Alpha-1-antitrypsin deficiency is a genetic condition associated with severe, early-onset chronic obstructive pulmonary disease (COPD). However, there is significant variability in lung function impairment among persons with the protease inhibitor ZZ genotype. Early identification of persons at highest risk of developing lung disease could be beneficial in guiding monitoring and treatment decisions. Using a multicenter, family-based study sample (2002-2005) of 372 persons with the protease inhibitor ZZ genotype, the authors developed prediction models for forced expiratory volume in 1 second (FEV(1)) and the presence of severe COPD using demographic, clinical, and genetic variables. Half of the data sample was used for model development, and the other half was used for model validation. In the training sample, variables found to be predictive of both FEV(1) and severe COPD were age, sex, pack-years of smoking, bronchodilator responsiveness, chronic bronchitis symptoms, and index case status. In the validation sample, the predictive model for FEV(1) explained 50% of the variance in FEV(1), and the model for severe COPD exhibited excellent discrimination (c statistic = 0.88).

Male fertility in cystic fibrosis

Infertility rates among males with cystic fibrosis (CF) approximate 97%. No information is currently available within Ireland determining an understanding of fertility issues and the best methods of information provision to this specialized group. This study aimed to determine understanding and preferred approaches to information provision on fertility issues to Irish CF males. A Descriptive Study utilizing prospective coded questionnaires was mailed to a male CF cohort (n=50). Sections included demographics, fertility knowledge & investigation. Response rate was 16/50 (32%). All were aware that CF affected their fertility. More than two-thirds (n=11) were able to provide explanations whilst only one-third (n=5) provided the correct explanation. Significant numbers stated thoughts of marriage and a future family. Half have discussed fertility with a healthcare professional (HCP). Mean age of discussion was 21.9 years. One third preferred an earlier discussion. The commonest first source for information was written material which was also the preferred source. Three-quarters requested further information preferring again, written material. Significant gaps in sex education of Irish CF males exist. Discussion should be initiated by HCPs and centre-directed written material devised to address deficiencies.

Heritability of lung function in severe alpha-1 antitrypsin deficiency

Severe alpha-1 antitrypsin (AAT) deficiency is a proven genetic risk factor for COPD, but there is marked variation in the development of COPD among AAT deficient subjects. To investigate familial aggregation of lung function in subjects with AAT deficiency, we estimated heritability for forced expiratory volume in 1 s (FEV1) and FEV1/forced vital capacity (FVC) in 378 AAT deficient subjects from 167 families in the AAT Genetic Modifiers Study; all subjects were verified homozygous for the Z AAT deficiency allele. Heritability was evaluated for models that included and excluded an ascertainment correction, as well as for models that excluded, included and were stratified by a cigarette smoking covariate. In models without an ascertainment correction, and in all models without a covariate for smoking, no evidence for familial aggregation of lung function was observed. In models conditioned on the index proband with covariates for smoking, post-bronchodilator FEV1/FVC demonstrated significant heritability (0.26 +/- 0.14, p = 0.03). When we limited the analysis to subjects with a smoking history, post-bronchodilator FEV1 demonstrated significant heritability (0.47 +/- 0.21, p = 0.02). Severity rate phenotypes were also assessed as potential phenotypes for genetic modifier studies. Significant heritability was found with all age-of-onset threshold models that included smoking and ascertainment adjustments. Using the t-distribution, the heritability estimates ranged from 0.43 to 0.64, depending on the age-of-onset of FEV1 decline used for the severity rate calculation. Correction for ascertainment and consideration of gene-by-smoking interactions will be crucial for the identification of genes that may modify susceptibility for COPD in families with AAT deficiency.

Alpha-1 antitrypsin deficiency: a conformational disease associated with lung and liver manifestations

Alpha-1 antitrypsin (A1AT) is a serine anti-protease produced chiefly by the liver. A1AT deficiency is a genetic disorder characterized by serum levels of less than 11 mumol/L and is associated with liver and lung manifestations. The liver disease, which occurs in up to 15% of A1AT-deficient individuals, is a result of toxic gain-of-function mutations in the A1AT gene, which cause the A1AT protein to fold aberrantly and accumulate in the endoplasmic reticulum of hepatocytes. The lung disease is associated with loss-of-function, specifically decreased anti-protease protection on the airway epithelial surface. The so-called 'Z' mutation in A1AT deficiency encodes a glutamic acid-to-lysine substitution at position 342 in A1AT and is the most common A1AT allele associated with disease. Here we review the current understanding of the molecular pathogenesis of A1AT deficiency and the best clinical management protocols.

Two case reports of pneumomediastinum

BACKGROUND

We present two cases of pneumomediastinum in patients who presented to the accident and emergency department of a large teaching hospital. One case had a history of inhalational drug abuse, which may have contributed to the event, while the other had no obvious precipitating factors.

AIMS

To evaluate the presenting symptoms, physical signs, diagnosis and management of pneumomediastinum with a review of the literature.

METHODS

We describe two cases of pneumomediastinum with a literature review.

CONCLUSIONS

Pneumomediastinum is an uncommon entity, first described almost 400 years ago. It presents with relatively non-specific symptoms and signs and will require radiological investigations to clarify the diagnosis. Treatment is conservative but will require close observation for the development of complications and occult visceral perforation. Complete resolution can be expected.

The role of secretory leucoprotease inhibitor in the resolution of inflammatory responses

Chronic lung disease is one of the most common causes of death and disability worldwide. This group of diseases is characterized by a protease burden, an infective process and a dominant pro-inflammatory profile. While SLPI (secretory leucoprotease inhibitor) was initially identified as a serine protease inhibitor, it has since been shown that SLPI possesses other properties distinct from those associated with its antiprotease capabilities that play an important role in protecting the host from infection and injury. In the course of this review, we will highlight the findings from a range of studies that illustrate the multiple functions of SLPI and its role in the resolution of the immune response.

Team Objective Structured Bedside Assessment (TOSBA): a novel and feasible way of providing formative teaching and assessment

It can be challenging to teach and assess medical students successfully in the setting of a hospital ward using real patients. We describe a novel method of providing weekly formative clinical assessment and teaching to final year students on an acute medical ward: The Team Objective Structured Bedside Assessment (TOSBA). The TOSBA involves three groups of five students rotating through three ward-based stations (each station consists of an inpatient and facilitator). Each group spends 25 minutes at a bedside station where the facilitator asks consecutive students to perform one of five clinical tasks. Every student receives a standardised grade and is provided with educational feedback at each of the three stations. We report our 15-month experience using the TOSBA format to assess and teach a large number of medical students on a weekly basis. We discuss the advantages and potential drawbacks of our approach.

Expression of HCLCA1 in cystic fibrosis lungs is associated with mucus overproduction

Mucus overproduction is typical in cystic fibrosis (CF) airway disease. The human calcium-activated chloride channel, hCLCA1, has been reported to be upregulated by interleukin (IL)-9 and to regulate the expression of mucins. Therefore, the expression of IL-9, IL-9 receptor (IL-9R) and hCLCA1 between the lungs of CF patients and healthy control subjects was compared. Endoscopic biopsy samples of bronchial mucosa from 10 CF patients and six control subjects were stained with periodic acid-Schiff. IL-9, IL-9R and hCLCA1 expression was determined by immunocytochemistry. Expression of hCLCA1 mRNA was also determined by in situ hybridisation. The present study found significant increases in IL-9, IL-9R and hCLCA1 immunoreactivity, hCLCA1 mRNA expression, and numbers of mucus-producing cells in the mucosa of CF patients compared to control subjects. Positive correlations were found between IL-9R-positive-cells with IL-9-positive cells and hCLCA1-positive cells, and between PAS-positive cells with hCLCA1-positive cells and IL-9R-positive cells. Expression of hCLCA1 mRNA was colocalised with IL-9R expression and PAS-positive staining in epithelial cells. Increased expression of interleukin-9 and interleukin-9 receptor, as well as an upregulation of the human calcium-activated chloride channel, hCLCA1, in mucus-producing epithelium of cystic fibrosis patients, support the hypothesis that interleukin-9 contributes to mucus overproduction in cystic fibrosis airway disease.

An outreach programme for patients with an exacerbation of chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease is a common clinical condition characterised by airflow obstruction. The clinical course of the disease is characterised by intermittent exacerbations. In Ireland exacerbations of chronic obstructive pulmonary disease are a common cause of admission to acute medical hospitals. The Beaumont Hospital COPD Outreach Programme was designed to provide care at home for patients with an exacerbation of COPD that would otherwise require hospitalisation. Patients recruited to the programme were discharged home within 72 hours of admission and reviewed by the Outreach Team over a two week period. In addition to monitoring clinical progress the Team provided education, smoking cessation and medication advice. Analysis of the outcome of the first 100 patients recruited to the study show that one third of patients admitted to Hospital with an exacerbation of COPD are eligible for this programme and the average length of Hospital stay was 2.6 days. During the fourteen day follow up there was one death (non-respiratory) and six patients were re-admitted to hospital. Forty percent of smokers had abstained from smoking at the end of three months. In summary, the COPD Outreach programme is a safe and effective alternative to acute hospital care for selected patients with exacerbations of COPD.

Association of IL-10 polymorphism with severity of illness in community acquired pneumonia

BACKGROUND

The influence of genetic polymorphisms of interleukin (IL)-10, tumour necrosis factor (TNF)-alpha, and IL-6 gene promoters on severity of systemic inflammatory response syndrome (SIRS) associated with community acquired pneumonia (CAP) was studied.

METHODS

Using PCR-RFLP analysis we analysed a -1082G/A single nucleotide polymorphism (SNP) of the anti-inflammatory IL-10 gene, a -308G/A SNP of the pro-inflammatory TNF-alpha gene and a -174G/C SNP of the IL-6 gene. Illness severity was stratified according to SIRS score, calculated by presence of up to four physiological indices: temperature, white blood cell count, heart rate and respiratory rate (non-SIRS, SIRS 2, SIRS 3, and SIRS 4).

RESULTS

A statistically significant stepwise increase in frequency of the IL-10 G allele, associated with higher expression of the gene, was observed in patients with increasing severity of illness from non-SIRS (n=19) to SIRS 2 (n=17), SIRS 3 (n=33) and SIRS 4 (n=24). This was primarily due to a higher frequency of the GG genotype with increasing severity from non-SIRS through to SIRS 4. IL-10 G allele frequency was also increased in patients who died as a result of CAP (n=11) compared with CAP survivors (n=82) (p=0.01). No association was seen between the TNF-alpha -308G/A and IL-6 -174G/C SNPs and disease. Additionally, no interaction between all three SNP genotypes and disease severity was observed.

CONCLUSIONS

A polymorphism affecting IL-10 expression may influence the severity of illness in patients with CAP.

Ambient pCO2 modulates intracellular pH, intracellular oxidant generation, and interleukin-8 secretion in human neutrophils

Although neutrophils are a critical component of the inflammatory process, their functional regulation is incompletely understood. Of note, although pCO2 varies physiologically and pathologically in the neutrophilic milieu, its affect on neutrophil biological processes is unresolved. We demonstrate here that neutrophils respond to hypo- and hypercarbia, (0.04% and 10%) by increasing and decreasing, respectively, intracellular oxidant production (basally and in response to opsonized Escherichia coli and phorbol esters). Further, hypo- and hypercarbia increase and decrease, respectively, the release of IL-8 from LPS-stimulated cells; both effects are attenuated by the carbonic anhydrase inhibitor, acetazolamide. Anion exchange did not restore pH(i) under hypocarbic conditions, however partial restoration of pH(i) under hypercarbic conditions was achieved by Na+/H+ exchange and vacuolar ATPases. Abrogation of pCO2-induced changes in pH(i) prevented hypocarbia-induced generation of reactive oxidant species. These observations suggest that CO2 modifies neutrophil activity significantly by altering pH(i).

Interleukin-8 up-regulation by neutrophil elastase is mediated by MyD88/IRAK/TRAF-6 in human bronchial epithelium

Cystic fibrosis is characterized in the lungs by neutrophil-dominated inflammation mediated significantly by neutrophil elastase (NE). Previous work has shown that NE induces interleukin-8 (IL-8) gene expression and protein secretion in bronchial epithelial cells. We sought to determine the intracellular mechanisms by which NE up-regulates IL-8 in bronchial epithelial cells. The data show that stimulation of 16HBE14o(-) cells with NE induced IL-8 protein production and gene expression. Both responses were abrogated by actinomycin D, indicating that regulation is at the transcriptional level. Electrophoretic mobility shift assays demonstrated that nuclear factor kappaB (NFkappaB) was activated in 16HBE14o(-) cells stimulated with NE. Western blot analysis demonstrated that activation of NFkappaB by NE was preceded by phosphorylation and degradation of IkappaB proteins, principally IkappaBbeta. In addition, we observed that interleukin-1 receptor-associated kinase (IRAK) was degraded in 16HBE14o(-) cells stimulated with NE. Quantification of IL-8 reporter gene activity by luminometry demonstrated that dominant negative MyD88 (MyD88Delta) or TRAF-6 (TRAF-6Delta) inhibited IL-8 reporter gene expression in response to NE. Furthermore, MyD88Delta inhibited NE-induced IRAK degradation. These results show that NE induces IL-8 gene up-regulation in bronchial epithelial cells through an IRAK signaling pathway involving both MyD88 and TRAF-6, resulting in degradation of IkappaBbeta and nuclear translocation of NFkappaB. These findings may have implications for therapeutic treatments in the cystic fibrosis condition.

Cathepsin B, L, and S cleave and inactivate secretory leucoprotease inhibitor

A number of serine proteases, matrix metalloproteases, and cysteine proteases were evaluated for their ability to cleave and inactivate the antiprotease, secretory leucoprotease inhibitor (SLPI). None of the serine proteases or the matrix metalloproteases examined cleaved the SLPI protein. However, incubation with cathepsins B, L, and S resulted in the cleavage and inactivation of SLPI. All three cathepsins initially cleaved SLPI between residues Thr(67) and Tyr(68). The proteolytic cleavage of SLPI by all three cathepsins resulted in the loss of the active site of SLPI and the inactivation of SLPI anti-neutrophil elastase capacity. Cleavage and inactivation were catalytic with respect to the cathepsins, so that the majority of a 400-fold excess of SLPI was inactivated within 15 min by cathepsins L and S. Analysis of epithelial lining fluid samples from individuals with emphysema indicated the presence of cleaved SLPI in these samples whereas only intact SLPI was observed in control epithelial lining fluid samples. Active cathepsin L was shown to be present in emphysema epithelial lining fluid and inhibition of this protease prevented the cleavage of recombinant SLPI added to emphysema epithelial lining fluid. Taken together with previous data that demonstrates that cathepsin L inactivates alpha(1)-antitrypsin, these findings indicate the involvement of cathepsins in the diminution of the lung antiprotease screen possibly leading to lung destruction in emphysema.

Anti-proteinase 3 antibody activation of neutrophils can be inhibited by alpha1-antitrypsin

Wegener's granulomatosis (WG) is classically associated with the presence of cytoplasmic antineutrophil cytoplasmic autoantibodies (c-ANCA). Proteinase 3 (PR3), the target antigen for c-ANCA, is inhibited by the antiprotease alpha1-antitrypsin (A1AT), and recent studies have demonstrated that WG patients who are A1AT-deficient have a worse clinical course, suggesting that a protease-antiprotease imbalance may play a role in WG. We evaluated the effect of A1AT on anti-PR3 antibody-induced activation of neutrophils. The neutrophil was chosen because of its central role in the pathogenesis of WG. Isolated neutrophils from healthy controls were incubated with tumor necrosis factor (TNF)-alpha to induce surface expression of PR3. Subsequently, they were stimulated with a monoclonal antibody to PR3, resulting in a significant increase in respiratory burst. Addition of A1AT (1 mg/ml) to the TNF-alpha- primed cells before the addition of the anti-PR3 antibody resulted in a 47% reduction in anti-PR3 antibody-induced activation. A1AT mediated this inhibitory action by preventing anti-PR3 antibody binding to PR3 on the cell, thereby preventing the PR3-FcgammaR11a cross-linkage required for cell activation. Further, anti-PR3 antibody-induced activation of neutrophils from WG patients can be reduced by 56% with A1AT. These data suggest that protease-antiprotease interactions may play a pivotal role in neutrophil activation in WG.

Alpha1-antitrypsin deficiency: biological answers to clinical questions

Alpha1-antitrypsin (alpha1AT) deficiency is a common lethal hereditary disorder of white persons of European descent. The condition is characterized by reduced serum levels of alpha1AT, a 52-kDa glycoprotein synthesized chiefly in the liver and, to a lesser extent, by macrophages and neutrophils. Alpha1AT acts as an antiprotease and is the physiological inhibitor of neutrophil serine proteases such as neutrophil elastase cathepsin G and proteinase 3. The clinical manifestations of alpha1AT deficiency occur chiefly in the lung, with a high risk of emphysema occurring by the third or fourth decade of life. Cigarette smoking accelerates the development of emphysema in persons with alpha1AT deficiency. There is also an increased risk of liver disease in alpha1AT deficiency, which occurs mostly in childhood. In this review, we will define further the diagnosis of alpha1AT deficiency and its clinical manifestations and describe the therapeutic strategies that are currently being developed to treat the hepatic and pulmonary disease associated with this condition.

Role of IL-18 in CD4+ T lymphocyte activation in sarcoidosis

Sarcoidosis is a granulomatous disease of unknown etiology associated with the expansion of IL-2-producing activated CD4(+) T lymphocytes. A number of factors including the recently described IL-18 have been implicated in IL-2 expression in vitro. We investigated the role of IL-18 in IL-2 expression in sarcoidosis. Eighteen individuals with sarcoidosis and 15 normal controls were studied. IL-18R expression and epithelial lining fluid (ELF) concentrations of IL-18 were significantly elevated in the sarcoid group (p = 0.0143 and 0.0024, respectively). Both AP1 and NF-kappaB, transcription factors that regulate IL-2 gene expression, were activated in vivo in sarcoid pulmonary CD4(+) T lymphocytes. Transcription factor activity was not detected in pulmonary CD4(+) T lymphocytes from normal controls or from peripheral blood CD4(+) T lymphocytes from individuals with sarcoidosis, further evidence of compartmentalization of the lymphoproliferative process in this condition. We examined the effects of IL-18 on AP1 and NF-kappaB in Jurkat T cells in vitro. These effects were both time and dose dependent. Examination of transcription factor activation and IL-2 gene expression in Jurkat T cells revealed that sarcoid but not normal ELF activated AP1 and NF-kappaB, induced IL-2 gene transcription, and up-regulated IL-2 protein production. Addition of IL-18 to normal ELF also induced IL-2 mRNA accumulation, whereas correspondent depletion of IL-18 from sarcoid ELF using neutralizing Abs abrogated all of the effects. These data strongly implicate IL-18 in the pathogenesis of sarcoidosis via activation of AP1 and NF-kappaB, leading to enhanced IL-2 gene expression and IL-2 protein production and concomitant T cell activation.

Oxidation of either methionine 351 or methionine 358 in alpha 1-antitrypsin causes loss of anti-neutrophil elastase activity

Hydrogen peroxide is a component of cigarette smoke known to be essential for inactivation of alpha(1)-antitrypsin, the primary inhibitor of neutrophil elastase. To establish the molecular basis of the inactivation of alpha(1)-antitrypsin, we determined the sites oxidized by hydrogen peroxide. Two of the nine methionines were particularly susceptible to oxidation. One was methionine 358, whose oxidation was known to cause loss of anti-elastase activity. The other, methionine 351, was as susceptible to oxidation as methionine 358. Its oxidation also resulted in loss of anti-elastase activity, an effect not previously recognized. The equal susceptibility of methionine 358 and methionine 351 to oxidation was confirmed by mass spectrometry. To verify this finding, we produced recombinant alpha(1)-antitrypsins in which one or both of the susceptible methionines were mutated to valine. M351V and M358V were not as rapidly inactivated as wild-type alpha1-antitrypsin, but only the double mutant M351V/M358V was markedly resistant to oxidative inactivation. We suggest that inactivation of alpha(1)-antitrypsin by oxidation of either methionine 351 or 358 provides a mechanism for regulation of its activity at sites of inflammation.

Altered intracellular pH regulation in neutrophils from patients with cystic fibrosis

Cystic fibrosis (CF) is a condition characterized by neutrophil-mediated lung damage and bacterial colonization. The physiological basis for reported functional alterations in CF neutrophils, including increased release of neutrophil elastase, myeloperoxidase, and oxidants, is unknown. These processes are, however, regulated by intracellular pH (pH(i)). We demonstrate here that pH(i) regulation is altered in neutrophils from CF patients. Although resting pH(i) is similar, pH(i) after acid loading and activation (N-formyl-methionyl-leucyl-phenylalanine and phorbol 12-myristate 13-acetate) is more acidic in CF cells than in normal cells. Furthermore, patients with non-CF-related bronchiectasis handle acid loading and activation in a fashion similar to subjects with normal neutrophils, suggesting that chronic pulmonary inflammation alone does not explain the difference in pH(i). This is further supported by data showing that normal neutrophils exposed to the CF pulmonary milieu respond by increasing pH(i) as opposed to decreasing pH(i) as seen in activated CF neutrophils. These pH(i) differences in activated or acid-loaded CF neutrophils are abrogated by ZnCl(2) but not by amiloride and bafilomycin A(1), suggesting that passive proton conductance is abnormal in CF. In addition, DIDS, which inhibits HCO(3)(-)/Cl(-) exchange, causes alkalinization of control but not of CF neutrophils, suggesting that anion transport is also abnormal in CF neutrophils. In summary, we have shown that pH(i) regulation in CF neutrophils is intrinsically abnormal, potentially contributing to the pulmonary manifestations of the condition.

Increased elastase release by CF neutrophils is mediated by tumor necrosis factor-alpha and interleukin-8

Cystic fibrosis (CF) is a lethal, hereditary disorder characterized by a neutrophil-dominated inflammation of the lung. We sought to determine whether neutrophils from individuals with CF release more neutrophil elastase (NE) than neutrophils from normal subjects. Our results showed that peripheral blood neutrophils (PBNs) from normal subjects and individuals with CF contained similar amounts of NE, but after preincubation with CF bronchoalveolar lavage (BAL) fluid, significantly more NE was released by CF PBNs, a release that was amplified further by incubation with opsonized Escherichia coli. To determine which components of CF BAL fluid stimulated this excessive NE release from CF PBNs, we repeated the experiments after neutralization or immunoprecipitation of tumor necrosis factor (TNF)-alpha and interleukin (IL)-8 in CF BAL fluid. We found that subsequent NE release from CF PBNs was reduced significantly when TNF-alpha and IL-8 were removed from CF BAL fluid. When TNF-alpha and IL-8 were used as activating stimuli, CF PBNs released significantly greater amounts of NE compared with PBNs from control subjects and individuals with bronchiectasis. These results indicate that CF PBNs respond abnormally to TNF-alpha and IL-8 in CF BAL fluid and react to opsonized bacteria by releasing more NE. This may help explain the increased NE burden seen in this condition.

Glutathione aerosol suppresses lung epithelial surface inflammatory cell-derived oxidants in cystic fibrosis

Cystic fibrosis (CF) is characterized by accumulation of activated neutrophils and macrophages on the respiratory epithelial surface (RES); these cells release toxic oxidants, which contribute to the marked epithelial derangements seen in CF. These deleterious consequences are magnified, since reduced glutathione (GSH), an antioxidant present in high concentrations in normal respiratory epithelial lining fluid (ELF), is deficient in CF ELF. To evaluate the feasibility of increasing ELF GSH levels and enhancing RES antioxidant protection, GSH aerosol was delivered (600 mg twice daily for 3 days) to seven patients with CF. ELF total, reduced, and oxidized GSH increased (P < 0.05, all compared with before GSH therapy), suggesting adequate RES delivery and utilization of GSH. Phorbol 12-myristate 13-acetate-stimulated superoxide anion (O2-.) release by ELF inflammatory cells decreased after GSH therapy (P < 0.002). This paralleled observations that GSH added in vitro to CF ELF inflammatory cells suppressed O2-. release (P < 0.001). No adverse effects were noted during treatment. Together, these observations demonstrate the feasibility of using GSH aerosol to restore RES oxidant-antioxidant balance in CF and support the rationale for further clinical evaluation.

Baseline characteristics of enrollees in the National Heart, Lung and Blood Institute Registry of alpha 1-antitrypsin deficiency. Alpha 1-Antitrypsin Deficiency Registry Study Group

OBJECTIVE

alpha 1-Antitrypsin (alpha 1-AT) deficiency is a hereditary disorder characterized by a high risk for the development of emphysema at an early age. In 1988, the National Heart, Lung and Blood Institute, National Institutes of Health, initiated a registry of individuals with alpha 1-AT deficiency to help define the natural history and clinical course of this disorder. This article describes demographic and clinical characteristics of subjects enrolled in the Registry at baseline.

DESIGN

Prospective longitudinal natural history study.

SETTING

Thirty-seven clinical centers in the United States (36 centers) and Canada (one center).

PATIENTS

There were 1,129 subjects 18 years of age or older with severe deficiency of alpha 1-AT, defined as having serum alpha 1-AT levels < or = 11 mumol/L confirmed by a Central Phenotyping Laboratory, or a ZZ or ZNull genotype identified by genomic DNA analysis.

RESULTS

Most enrollees were symptomatic white subjects in their fourth to sixth decade, with a ZZ phenotype, a history of having smoked cigarettes, and pulmonary function tests demonstrating a pattern consistent with emphysema. Interestingly, only a small percentage were current smokers on enrollment, suggesting that this population is amenable to smoking cessation. A subgroup of individuals in the Registry with relatively normal lung function were younger, more likely to have never smoked and more likely to have come to medical attention owing to a family history of alpha 1-AT deficiency rather than symptomatic involvement.

CONCLUSIONS

These results emphasize the need for increased awareness and early detection of alpha 1-AT deficiency. In this endeavor, dissemination of the information contained in the Registry to health-care professionals and the general population, along with initiation of appropriate preventative measures before significant lung damage has occurred, could have considerable benefits for individuals with this condition.

Is gene therapy in cystic fibrosis a realistic expectation?

To date there are 11 human protocols either ongoing or approved for gene therapy for cystic fibrosis (CF) in the United States. There are also two protocols in the United Kingdom and one in France. Of these, results have been published in four. The protocols vary in the cells targeted, the vectors used, and the frequency of administration, but despite these differences all have contributed toward answering the key questions that will determine the future of gene therapy for CF: the questions of efficacy and safety. These studies have demonstrated that it is feasible to transfer the normal human CF transmembrane conductance regulator complementary DNA to the respiratory epithelium and that this will lead to production of normal CF transmembrane conductance regulator protein and in some cases to a physiologic response. The most frequently used vector is the adenovirus. Obstacles to be overcome with this system include the need for improved and prolonged expression, efficacy on repeat administration, and decreased inflammation. Recent work on the immune response to adenoviral vectors may help achieve these goals. The cationic lipid method of gene delivery is less likely than adenovirus to cause inflammation, at least in the nose, but improved efficacy of gene transfer is necessary as well as improved complex stability. Furthermore, this system has yet to be tested in the lungs of individuals with CF. Finally, the adeno-associated virus, the other vector approved for human gene therapy studies in CF, has shown some promise in preclinical studies but remains to be tested in humans. The results of these studies give some cause for guarded optimism, but point out a number of problems that must be overcome before gene therapy for CF delivers on the promise of a safe effective treatment for this condition.

Molecular characterization of a glycosylphosphatidylinositol-linked ADP-ribosyltransferase from lymphocytes

Mono ADP-ribosyltransferases catalyze the transfer of the ADP-ribose moiety of nicotinamide adenine dinucleotide (NAD) to proteins. It was reported by Wang et al (J Immunol 153:4048, 1994) that incubation of mouse cytotoxic T lymphocytes (CTL) with NAD resulted in the ADP-ribosylation of membrane proteins and inhibition of cell proliferation and cytotoxicity. Treatment of CTL with phosphatidylinositol-specific phospholipase C (PI-PLC) before incubation with NAD prevented the inhibitory effects of NAD on the cells, consistent with the removal of a glycosylphosphatidylinositol (GPI)-anchored ADP-ribosyltransferase on the lymphocyte surface. We have identified and cloned a GPI-linked ADP-ribosyltransferase from Yac-1 mouse T-cell lymphoma cells. The deduced amino acid sequence of the Yac-1 transferase was 70% and 41% identical to those of the rabbit skeletal muscle and chicken heterophil, respectively. It contained three noncontiguous sequences similar to those found in several of the bacterial toxin and vertebrate ADP-ribosyltransferases. Based on crystallography of the bacterial toxins, these regions are believed to form, in part, the catalytic site consistent with a common mechanism for the ADP-ribose transfer reaction. In rat mammary adenocarcinoma (NMU) cells transformed with the Yac-1 transferase cDNA, transferase activity was present on the cell surface and was released into the medium by treatment of cells with PI-PLC. Thus, we have cloned a novel gene that has properties identical to the transferase detected in CTL, and may be involved in the NAD-dependent regulation of proliferation and cytotoxicity.

Quantitative assessment of the epithelial and inflammatory cell populations in large airways of normals and individuals with cystic fibrosis

Nasal and bronchial brushings and bronchial biopsies were evaluated from patients with cystic fibrosis (CF) and from normal subjects to quantify epithelial and inflammatory cell types. Epithelial in both groups were dominated by ciliated cells. The relative proportions of epithelial cells recovered by brushing and biopsy were similar, but with more basal cells from biopsies than from brushings. In nasal brushings, the numbers and percentages of epithelial subtypes were similar in both groups. In bronchial brushings, the number of recovered cells was 2.5-fold increased in the CF group compared with that in the normal group because of large numbers of neutrophils. The proportion of ciliated cells was lower in the CF group than in the normal group. Thus, even though the CF transmembrane conductance regulator mutations are expressed similarly in the nasal and bronchial epithelium in CF, the consequences are different, with little inflammation and no changes in the proportions of epithelial cells in the nasal epithelium, compared with marked neutrophil inflammation on the epithelial surface and significant changes in epithelial populations in the large airways. Airway brushing permits repetitive evaluation of the airway epithelium in CF, a useful methodology in the assessment of new therapies for this disorder.

Modification of nasal epithelial potential differences of individuals with cystic fibrosis consequent to local administration of a normal CFTR cDNA adenovirus gene transfer vector

Mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR) manifest on the nasal epithelial surface of individuals with cystic fibrosis (CF) by Na+ hyperabsorption and diminished beta-agonist-induced Cl- conductance, resulting in an abnormal bioelectric phenotype across the nasal epithelium. A clinical trial was conducted to determine if a replication-deficient, recombinant adenovirus vector containing a normal copy of the CFTR cDNA (AdCFTR) could, when administered to the nasal epithelium, correct the abnormal bioelectric phenotype. Nine individuals with CF received 2 x 10(5) to 2 x 10(8.5) plaque forming units of AdCFTR to the epithelium of one nostril. Measurements made included: baseline electrical potential difference (PD) between the surface of the nasal epithelium and the interstitial fluid, change in PD in response to amiloride, which inhibits apical Na+ channels, and change in PD in response to isoproterenol in a low Cl- solution, a measure of cAMP-regulated Cl- conductance. The functional integrity of the epithelium was evaluated by the PD response to ATP. Each individual served as their own control with measurements made in the nostril to be treated before AdCFTR administration, and in the contralateral untreated nostril. On the average, in the treated nostril over 2 weeks after the local administration of the adenovirus vector compared to measurements made in the same nostril before treatment, baseline PD decreased toward normal (-53.3 +/- 4.0 to -34.6 +/- 3.4, p = 0.01), response to amiloride decreased toward normal (36.9 +/- 4.7 to 19.7 +/- 3.0, p = 0.02), and response to low Cl- and isoproterenol increased toward normal (-4.5 +/- 1.5 to -9.1 +/- 2.1, p = 0.05). There were no changes in response to ATP (-15.3 +/- 2.7 to -15.8 +/- 1.9, p = 0.39), suggesting that the epithelium remained functionally intact. Importantly, there were no significant changes in measurements made in the untreated nostril. While limited to the nasal epithelium, these data suggest an adenovirus vector can safely deliver sufficient CFTR cDNA function to improve the abnormal CF bioelectric phenotype.

Gene therapy for the respiratory manifestations of cystic fibrosis

Cystic fibrosis (CF) is caused by mutations of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The major manifestations are on the airway epithelial surface, with purulent mucus, recurrent infections, chronic inflammation, and loss of lung function. Consequent to mutations in both parental genes, airway epithelial cells have insufficient CFTR function. Because this can be corrected in vitro by transfer of the normal CFTR gene into airway epithelial cells, it is reasonable to hypothesize that the respiratory manifestations of CF could be prevented by transfer of the normal human CFTR cDNA to the airway epithelium in vivo. Over the past 6 years, our laboratory has developed a strategy to accomplish this goal using a replication deficient E1-E3- recombinant adenovirus (Ad) serotype 5 vector containing the normal human CFTR cDNA (AdCFTR). Studies with experimental animals demonstrate that with administration of such a vector to the airways, the human CFTR cDNA could be transferred to the airway epithelium, with expression of the human CFTR cDNA for at least 6 weeks. Extensive preclinical studies in vitro and in vivo demonstrated that the risks to humans were sufficiently low to initiate a Phase I trial using the AdCFTR vector to treat the respiratory manifestations of CF in humans. Following approval by the National Heart, Lung, and Blood Institute Institutional Review Board, the National Institutes of Health Biosafety Committee, the National Institutes of Health Recombinant DNA Advisory Committee, and the Food and Drug Administration, we initiated the first human trial of gene therapy for CF on April 17, 1993. The clinical study is still ongoing, with safety and efficacy data being evaluated, but there is clear evidence that it is feasible to transfer and express the normal CFTR cDNA to the airway epithelium in vivo in individuals with CF.

Administration of an adenovirus containing the human CFTR cDNA to the respiratory tract of individuals with cystic fibrosis

We have administered a recombinant adenovirus vector (AdCFTR) containing the normal human CFTR cDNA to the nasal and bronchial epithelium of four individuals with cystic fibrosis (CF). We show that this vector can express the CFTR cDNA in the CF respiratory epithelium in vivo. With doses up to 2 x 10(9) pfu, there was no recombination/complementation or shedding of the vector or rise of neutralizing antibody titres. At 2 x 10(9) pfu, a transient systemic and pulmonary syndrome was observed, possibly mediated by interleukin-6. Follow-up at 6-12 months demonstrated no long term adverse effects. Thus, it is feasible to use an adenovirus vector to transfer and express the CFTR cDNA in the respiratory epithelium of individuals with CF. Correction of the CF phenotype of the airway epithelium might be achieved with this strategy.

Protease-antiprotease imbalance in the lungs of children with cystic fibrosis

Cystic fibrosis (CF) is characterized in the lung by chronic purulent bronchitis culminating in pulmonary insufficiency. There is evidence to suggest that neutrophil elastase (NE) released by neutrophils on the respiratory epithelial surface plays a major role in the pathogenesis of this lung disease. This study sought to determine the age of onset of the chronic neutrophil-dominated inflammation in CF and the consequences to the NE-anti-NE screen on the respiratory epithelial surface of the CF lung. NE and anti-NE defensive molecules were evaluated in respiratory epithelial lining fluid (ELF) in 27 children with stable CF (1 to 18 yr of age). Despite normal antigenic concentrations of alpha 1-antitrypsin (alpha 1AT) and secretory leukoprotease inhibitor (SLPI), 25 of 27 children with CF had neutrophil-dominated inflammation (> 500 neutrophils/microliters ELF). Active NE was found in ELF in 20 of 27 children, including two of four aged 1 yr. Western blot analysis showed the majority of alpha 1AT and SLPI molecules to be complexed and/or degraded. These observations demonstrate that a chronic imbalance of the NE-anti-NE protective screen develops early on the respiratory epithelial surface in persons with CF and is likely well established by 1 yr of age, with resultant potential for lung damage.

Prediction of heart rate and oxygen uptake during incremental and maximal exercise in healthy adults

Measurement of heart rate and oxygen uptake during incremental exercise and at maximal exercise is useful in evaluating mechanisms responsible for exercise limitation in patients with cardiopulmonary disease. Presently used prediction equations are based on relatively small groups of subjects in whom there was an uneven distribution of subjects with regard to age and sex or based on equations that were from extrapolated data. Our prediction equations are based on data from 231 men and women equally divided within decades between 20 and 80 years. Patients exercised to a symptom-limited maximum on a cycle ergometer while measurements of heart rate and oxygen uptake were recorded. The relationship between heart rate and oxygen uptake throughout exercise (HR:VO2) was determined using a statistical technique that included each data point from each subject. The HR:VO2 throughout incremental exercise was best described by separate equations for women younger than 50 years and older than 50 years and for men younger than 70 years and older than 70 years. Prediction equations for maximal heart rate (HRmax) and maximal oxygen uptake (VO2max) were developed by linear regression and were selected from all possible combinations of parameters. The HRmax was most accurately predicted by age alone for both sexes. Unlike the HR:VO2 relationship, the slope of the line relating heart rate to age was not different for the older women compared with the younger women so that a single equation was derived to predict HRmax. A single equation for the men was also sufficient since the slope of heart rate to age was the same for all ages. To most accurately predict VO2max, a separate equation was required for both the women and men that included age, height, and weight.

Systemic deficiency of glutathione in cystic fibrosis

Cystic fibrosis (CF), a disorder characterized by mutations of the CF transmembrane regulator gene, is characterized in the lung by chronic inflammation, leading to progressive damage to the airway epithelium, bronchiectasis, and chronic obstructive lung disease. One process contributing to the airway derangement is the chronic burden of oxidants released by inflammatory cells on the respiratory epithelial surface. With this background, we hypothesized that glutathione in respiratory epithelial lining fluid (ELF) in CF patients might be oxidized and/or diminished in amount compared with that in normal subjects. Recovery of ELF by bronchoalveolar lavage from young adults with CF (n = 21) and normal subjects (n = 25) demonstrated marked neutrophil-dominated inflammation in ELF in CF patients. As predicted, ELF in CF patients was characterized by a deficiency of glutathione (P < 0.001), but this was secondary to a reduction in reduced glutathione (P < 0.001), inasmuch as there were no differences in ELF levels of oxidized glutathione (P > 0.2). Unexpectedly, there was also a marked deficiency of reduced glutathione in plasma (P < 0.02); i.e., the glutathione "deficiency" observed in ELF in CF patients is not limited to the site of the inflammation but is systemic. Although the etiology of this generalized deficiency of extracellular glutathione is unknown, it is important in considering options for treating the concomitant and devastating lung pathology in this disorder.

Pharmacokinetics of recombinant secretory leukoprotease inhibitor aerosolized to normals and individuals with cystic fibrosis

Recombinant secretory leukoprotease inhibitor (rSLPI), a recombinant form of a natural airway inhibitor of neutrophil elastase (NE), is a potential therapeutic agent for cystic fibrosis (CF), a condition characterized by airway derangement mediated in part by the large burden of NE on the CF respiratory epithelial surface. After in vitro studies that demonstrated that aerosolized rSLPI retains its form and function, rSLPI was administered via aerosol to normal individuals and individuals with CF to determine the pharmacokinetics of in vivo rSLPI augmentation of the anti-NE defenses of the respiratory epithelial surface. After rSLPI aerosolization to normal individuals (100 mg single dose or 100 mg twice daily for 1 wk) there was a marked increase in SLPI levels and anti-NE capacity in airway epithelial lining fluid (ELF) at 1 h, diminishing gradually over 4 to 12 h. Interestingly, the ELF SLPI levels and anti-NE capacity achieved 12 h after 1 wk of rSLPI aerosols were no different than those 12 h after a single dose of rSLPI, suggesting that rSLPI does not accumulate on the respiratory epithelial surface after aerosolization. The ability of rSLPI to suppress NE in vivo was evaluated by aerosolization of rSLPI to individuals with CF, first as an escalating dose to assess safety, and then at doses of 100 mg twice daily for 1 wk or 50 mg twice daily for 2 wk.(ABSTRACT TRUNCATED AT 250 WORDS)

Recombinant secretory leukoprotease inhibitor augments glutathione levels in lung epithelial lining fluid

Secretory leukoprotease inhibitor (SLPI), a 12-kDa serine antiprotease, serves as the major inhibitor of neutrophil elastase (NE) on the epithelial surface of the upper airways. As a control for studies to evaluate the aerosol administration of recombinant SLPI (rSLPI) to augment the anti-NE defenses of the lung, the status of antioxidants in respiratory epithelial lining fluid (ELF) was evaluated. Unexpectedly, aerosol administration of rSLPI caused an elevation in ELF glutathione, a major component of the epithelial antioxidant screen; i.e., rSLPI may provide not only augmentation of anti-NE defenses but also antioxidant defenses. To evaluate this concept, rSLPI (100 mg) was aerosolized to sheep, and SLPI, glutathione, anti-NE capacity, and anti-H2O2 capacity were evaluated in respiratory ELF over a 30-h period. As expected, aerosolization of rSLPI increased ELF SLPI levels and anti-NE capacity. Strikingly, postaerosol levels of glutathione in ELF were also increased (5-fold 24 h after aerosol), with a concomitant increase in ELF anti-H2O2 capacity; i.e., the rSLPI augmented the antioxidant screen of ELF. This suggests that rSLPI may be particularly well suited for therapy in lung diseases characterized by excess of both serine proteases and oxidants on the respiratory epithelial surface.