Claus Vogelmeier

Identification of a novel, multifunctional beta-defensin (human beta-defensin 3) with specific antimicrobial activity. Its interaction with plasma membranes of Xenopus oocytes and the induction of macrophage chemoattraction.

Abstract. Previous studies have shown the implication of β-defensins in host defense of the human body. The human β-defensins 1 and 2 (hBD-1, hBD-2) have been isolated by biochemical methods. Here we report the identification of a third human β-defensin, called human β-defensin 3 (hBD-3; cDNA sequence, Genbank accession no. AF295370), based on bioinformatics and functional genomic analysis. Expression of hBD-3 is detected throughout epithelia of many organs and in non-epithelial tissues. In contrast to hBD-2, which is upregulated by microorganisms or tumor necrosis factor-α (TNF-α), hBD-3 expression is increased particularly after stimulation by interferon-γ. Synthetic hBD-3 exhibits a strong antimicrobial activity against gram-negative and gram-positive bacteria and fungi, including Burkholderia cepacia. In addition, hBD-3 activates monocytes and elicits ion channel activity in biomembranes, specifically in oocytes of Xenopus laevis. This paper also shows that screening of genomic sequences is a valuable tool with which to identify novel regulatory peptides. Human β-defensins represent a family of antimicrobial peptides differentially expressed in most tissues, regulated by specific mechanisms, and exerting physiological functions not only related to direct host defense.

Functional significance of cardiac reinnervation in heart transplant recipients

BACKGROUNDnThere is accumulating evidence of structural sympathetic reinnervation after human cardiac transplantation. However, the functional significance of reinnervation in terms of exercise capacity has not been established as yet; we therefore investigated the influence of reinnervation on cardiopulmonary exercise testing.nnnMETHODSnAfter orthotopic heart transplantation 35 patients (mean age, 49.1 +/- 8.4 years) underwent positron emission tomography with scintigraphically measured uptake of C11-hydroxyephedrine (HED), lung function testing, and cardiopulmonary exercise testing. Two groups were defined based on scintigraphic findings, indicating a denervated group (n = 15) with a HED uptake of 5.45%/min and a reinnervated group (n = 20) with a HED uptake of 10.59%/min.nnnRESULTSnThe two study groups did not show significant differences with regard to anthropometric data, number of rejection episodes, preoperative hemodynamics, and postoperative lung function data. The reinnervated group had a significant longer time interval from transplantation (1625 +/- 1069 versus 800 +/- 1316 days, p < .05). In transplant recipients with reinnervation, heart rate at maximum exercise (137 +/- 15 versus 120 +/- 20 beats/min, p = .012), peak oxygen uptake (21.0 +/- 4 versus 16.1 +/- 5 mL/min/kg, p = .006), peak oxygen pulse (12.4 +/- 2.9 versus 10.2 +/- 2.7 mL/min/beat, p = .031), and anaerobic threshold (11.2 +/- 1.8 versus 9.5 +/- 2.1 mL/min, p = .046) were significantly increased in comparison to denervated transplant recipients. Additionally, a decreased functional dead space ventilation (0.24 +/- 0.05 versus 0.30 +/- 0.05, p = .004) was observed in the reinnervated group.nnnCONCLUSIONSnOur study results support the hypothesis that partial sympathetic reinnervation after cardiac transplantation is of functional significance. Sympathetic reinnervation enables an increased peak oxygen uptake. This is most probably due to partial restoration of the chronotropic and inotropic competence of the heart as well as an improved oxygen delivery to the exercising muscles and a reduced ventilation-perfusion mismatching.

Intracellular glutathione and bronchoalveolar cells in fibrosing alveolitis: effects of N-acetylcysteine

Extracellular glutathione deficiency and exaggerated oxidative stress may contribute to the pathogenesis of fibrosing alveolitis (FA). High-dose N-acetylcysteine (NAC) supplementation partially reverses extracellular glutathione depletion and oxidative damage, but effects on intracellular glutathione are unknown. Intracellular total glutathione (GSHt) and activation of bronchoalveolar lavage cells (BAC) obtained from 18 FA patients (9 males, aged 52±2u2005yrs), before and after 12 weeks of oral NAC (600u2005mg t.i.d.), were assessed. Eight healthy nonsmokers (2 males, aged 36±6u2005yrs) served as a control group. Intracellular GSHt was decreased in FA (1.57±0.20u2005nmol·1×106 BAC−1 versus 2.78±0.43u2005nmol·106 BAC−1). After NAC treatment, the intracellular GSHt content increased (1.57±0.20 versus 1.87±0.19u2005nmol·1×106 BAC−1). The spontaneous oxidative activity of BAC decreased after NAC treatment (2.7±0.8 versus 1.0±0.2u2005nmol·1×106 BAC−1·h−1). Interleukin-8 concentration (82.1±31.5 versus 80.0±22.6u2005pg·mL bronchoalveolar fluid (BALF), nonsignificant (ns)) and myeloperoxidase activity (1.93±0.64 versus 1.55±0.47u2005mU·mL−1 BALF, ns) did not change significantly, but were found to be inversely correlated to intracellular GSHt. In conclusion, high-dose N-acetylcysteine supplementation increases intracellular glutathione levels slightly. This increase is associated with a mild reduction of oxidative activity but not with a reduction of bronchoalveolar cell activation in these patients.

Increased oxidation of extracellular glutathione by bronchoalveolar inflammatory cells in diffuse fibrosing alveolitis.

An unbalanced oxidative stress is thought to be an important element in the pathogenesis of diffuse fibrosing alveolitis (DFA). The purpose of our study was to investigate the role of reactive oxygen metabolites (ROMs) released from cultured bronchoalveolar inflammatory cells (BA-cells) on glutathione oxidation. We studied bronchoalveolar lavage samples from 10 healthy controls and from 20 patients with diffuse fibrosing alveolitis (all were nonsmokers). BA-cells obtained by bronchoalveolar lavage (BAL) were incubated with 50 microM of reduced glutathione (GSH). Oxidation of GSH to glutathione disulphide (GSSG) by BA-cell derived oxidants was detected as a decline of GSH in the supernatants. Total glutathione (GSHtot = GSH + 2 GSSG) and GSSG in the epithelial lining fluid (ELF), and methionine sulphoxide (Met(O)) content of BAL proteins were determined. In diffuse fibrosing alveolitis the oxidative activity of BA-cells was enhanced, GSHtot and GSH were decreased, whereas the GSSG:GSH ratio was increased. The oxidative activity of BA-cells correlated positively with the GSSG:GSH ratio, but not with the methionine sulphoxide content. The methionine sulphoxide content was elevated in diffuse fibrosing alveolitis and inversely correlated with GSHtot. The methionine sulphoxide content also correlated positively with the percentage of BAL neutrophils. We conclude that BA-cell-derived reactive oxygen species are capable of oxidizing extracellular GSH in vitro. The positive correlation between the BA-cell oxidative activity in vitro and GSSG:GSH ratio in ELF suggests that a similar oxidative effect on extracellular GSH may also occur in vivo.(ABSTRACT TRUNCATED AT 250 WORDS)

Lymphangioleiomyomatosis: Recurrence after single lung transplantation

Lymphangioleiomyomatosis (LAM) is a rare disease which afflicts young women of childbearing age. Recently, it has been listed as an indication for lung transplantation. We describe a case of recurrent LAM in a 31-year-old woman occurring in the allograft of a male donor after single lung transplantation. Nonisotopic in situ hybridization shows that the smooth muscle cell proliferation is of donor origin.

Comparative loss of activity of recombinant secretory leukoprotease inhibitor and alpha 1-protease inhibitor caused by different forms of oxidative stress

Secretory leukoprotease inhibitor (SLPI) and alpha 1-protease inhibitor (alpha 1-PI) are powerful antiproteases currently under investigation for their potential to protect the lung from neutrophil elastase (NE). The aim of this study was to determine whether the recombinant form of SLPI (rSLPI) and alpha 1-PI show different grades of loss of inhibitory activity when exposed to reactive oxygen metabolites. We incubated rSLPI and alpha 1-PI with N-chlorosuccinimide (NCS), chloramines, activated polymorphonuclear leucocytes (PMNs) and activated alveolar macrophages (AMs). Under all conditions evaluated, both antiproteases were partially inactivated. The resulting anti-NE activity of rSLPI was not significantly different from that of alpha 1-PI after exposure to NCS (p > 0.5), chloramines (p > 0.6), activated PMNs (p > 0.07) and activated AMs (p > 0.9). In conclusion, recombinant secretory leukoprotease inhibitor and alpha 1-protease inhibitor lose antineutrophil elastase activity to a similar extent when exposed to conditions that may be present in inflammatory lung disorders.

Long-Term Augmentation Therapy in Twenty Patients with Severe Alpha-1-Antitrypsin Deficiency – Three-Year Follow-Up

The purpose of this uncontrolled, prospective study was to evaluate the influence of long-term augmentation therapy with plasma-derived alpha 1-antitrypsin (AAT) on lung function parameters in patients with severe emphysema caused by AAT deficiency. Twenty patients (mean age 48 years) received AAT infusions once weekly for up to 36 months. No adverse effects were observed. At the beginning of the study, mean (+/- SEM) FEV1 was 1.35 +/- 0.12 liters and mean TLCO was 54 +/- 4% of predicted. After 36 months of treatment, mean FEV1 was 1.25 +/- 0.12 liters (p = n.s) and the TLCO was 52 +/- 4% predicted (p = n.s). Similar values were obtained before and after therapy for FVC (2.79 +/- 0.23 vs. 2.82 +/- 0.21 liters), MEF50 (0.72 +/- 0.09 vs. 0.68 +/- 0.08 liters/s), RV (4.60 +/0 0.44 vs 4.45 +/- 0.311) and TLC (7.72 +/- 0.49 vs. 7.38 +/- 0.42 l). The calculated annual loss of FEV1 (35.6 ml/year) was smaller than in historical untreated patients with AAT deficiency.

Bronchial epithelial cell B7-1 and B7-2 mRNA expression after lung transplantation: a role in allograft rejection?

Obliterative bronchiolitis is commonly interpreted as chronic rejection and involves the bronchial and bronchiolar epithelium. Upregulation of major histocompatibility complex (MHC) II on bronchial epithelial cells (BEC) had been hypothesised to be an important trigger of a bronchus directed rejection response. More recently, the additional expression of the costimulatory molecules B7-1 (CD80) and B7-2 (CD86) on antigen presenting cells were found to play an important role in the activation of T-lymphocytes in transplant rejection. The role of the expression of these molecules by BEC is unclear. BEC obtained by bronchial brushing and bronchoalveolar lavage fluid (BALF) cells from lung transplant recipients were studied and evaluated for messenger ribonucleic acid (mRNA) expression of B7-1 and B7-2 by semi-quantitative reverse transcriptase-polymerase chain reaction. Significantly elevated B7-1/glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA ratios were found in BEC from patients examined during the first 3u2005months after lung transplantation. Interestingly, in a small group of patients with bronchiolitis obliterans syndrome the B7-1/GAPDH and B7-2/GAPDH ratios were significantly elevated for BEC, whereas no differences were found for the BALF cells. In summary, B7 messenger ribonucleic acid expression by bronchial epithelial cells may play a role in (chronic) lung allograft rejection.

Isocyanate-induced asthma: results of inhalation tests with TDI, MDI and methacholine.

SummaryWe performed diisocyanate inhalation tests (maximal concentration, 20 ppb; exposure time, 1–2h) using toluene diisocyanate (TDI, n = 15) and diphenylmethane diisocyanate(MDI, n = 7) as well as methacholine challenges in 19 workers who had a clinical history of TDI/MDI-induced asthma. Additionally we tested volunteers who had no previous contact with diisocyanates: 10 healthy individuals with a negative methacholine test and 14 patients with asthma and a positive methacholine test were exposed to TDI. In all, 1 of the normal volunteers and 3 of the patients with asthma unrelated to diisocyanates showed a positive airway reaction to TDI, and 13 of the 19 diisocyanate workers displayed a positive result in the TDI/MDI inhalation test; however, only 6 of these 13 individuals reacted to methacholine. Furthermore, 3 of the 6 patients with a negative TDI/MDI challenge test demonstrated a significant response to methacholine. We conclude that bronchial hyperreactivity as evaluated by the methacholine challenge test is not closely related to isocyanate-induced bronchoconstriction and, therefore, the metacholine challenge is only of limited diagnostic value in patients with suspected isocyanate-induced asthma.

Immunophenotyping of lymphocyte subsets in bronchoalveolar lavage fluid Comparison of flow cytometric and immunocytochemical techniques

In order to compare flow cytometry with the conventional peroxidase anti-peroxidase method for the immunophenotyping of bronchoalveolar lavage fluid (BALF) lymphocytes, we studied BALF samples from 27 patients with various interstitial lung diseases. The results achieved with both methods were consistent concerning CD3+ pan T cells, CD4+ T helper/inducer, CD8+ T suppressor/cytotoxic and CD57+ natural killer cells. In contrast, a statistically significant lower anti-HLA-DR positive subset was obtained with flow cytometry than with the immunoperoxidase method (p less than 0.005). Since regression analyses and reliability counts showed further agreement between the methods, we conclude that flow cytometric immunophenotyping of BALF lymphocytes leads to similar, if not better, subset analyses than the immunoperoxidase method.