Metallothionein expression in human lung and its varying levels after lung transplantation. Toulouse Lung Transplantation Group.

The aim of this study was to determine the lung levels of metallothionein (MT), a free radical scavenger, because oxygen-derivated free radicals (ODFRs) have been involved both in reperfusion injury of transplanted lungs and in cardiac or renal allograft destruction. First, MT localization was evaluated in 14 normal human lung biopsy specimens. Then, in lung transplant recipients, MT content in BAL fluid (BALF) and its transcription rate in alveolar macrophages (AMs) were determined. The BALFs of 69 patients were separated into six groups: lung transplant recipients in clinically stable condition (CSR), those with acute rejection (AR), asymptomatic cytomegalovirus infection (ACMV), cytomegalovirus pneumonitis (CMVP), bronchiolitis obliterans syndrome (BOS), and patients without transplants who served as control subjects (NTCs). In normal lungs, 83% of AMs were positively stained. MT staining was also observed in pleural endothelial cells and basal cells from bronchial epithelium. In lung transplant recipients, MT levels in BALF were significantly higher in patients with CSR, AR, ACMV, and CMVP compared with NTCs, while during BOS, MT had a significantly lower level compared with other lung transplant groups. However, no difference among groups was found concerning MT-II messenger RNA expression in AMs, showing that, as in normal lung, AMs are not the only cells that produce MT. These data report for the first time to our knowledge MT cell distribution in human lung with specific emphasis on its enhanced levels after lung transplantation, even in the absence of complication. Possible correlation among MT levels, ODFRs, cytokine levels, and corticosteroid treatment during complications of lung transplantation are discussed.

[Lung pathology in heart, liver and kidney transplantation in adults]. / Pathologies pulmonaires dans la transplantation cardiaque, hépatique et rénale chez l'adulte.

Currently transplantation constitutes the only treatment for terminal heart, liver or renal failure. Post-transplantation complications remain numerous and sometimes fatal. The rejection of the organ, acute or chronic, and secondary infections due to immunosuppression are the most frequent complications that are observed. Added to this are the complications of the surgery itself and also the non-infectious complications of the immunosuppressive drugs. Pulmonary complications contribute an important factor to the post-graft morbidity and mortality. The majority of heart and liver transplants develop pulmonary complications principally in the first six months after graft. The immediate post-operative complications such as atelectasis, pleural effusion and pulmonary oedema are the most frequent but the infectious complications are much the most serious and are responsible for a significant part of the mortality. In renal transplantation pulmonary complications are above all infectious and are much less common than in cardiac or hepatic transplantation. An early diagnosis of the type of complication constitutes a major prognostic factor in immunodepressed patients. Thus, the practising pneumologist must thoroughly know the principal respiratory complications of solid organ transplant.

Tumour necrosis factor-alpha gene expression by alveolar macrophages in human lung allograft recipient with recurrence of sarcoidosis. Toulouse Lung Transplantation Group.

Recurrence of sarcoidosis in lung allografts is an interesting model to study the pathogenesis of this disease. We report a case of sarcoidosis recurrence in a single lung allograft recipient 2 years after transplantation. The expression of tumour necrosis factor-alpha (TNF-alpha) gene by alveolar macrophages was monitored. The TNF-alpha gene was not expressed at the time of recurrence of sarcoidosis, but only later when prominent granulomas were observed.

Alveolar macrophages from patients with beryllium disease and sarcoidosis express increased levels of mRNA for tumor necrosis factor-alpha and interleukin-6 but not interleukin-1 beta.

Recent evidence suggests that the alveolar macrophage-derived cytokines tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), and interleukin-6 (IL-6) play important roles in granulomatous diseases. Our objective was to quantify the mRNA for these cytokines in beryllium disease, a human granulomatous disease of known etiology. We hypothesized that alveolar macrophages and bronchoalveolar lavage fluid from patients with beryllium disease and sarcoidosis would express increased levels of mRNA and proteins, respectively, for TNF-alpha, IL-1 beta, and IL-6 compared with those of normal individuals. We performed bronchoalveolar lavage and used a quantitative polymerase chain reaction to determine alveolar macrophage-derived cytokine gene expression. We determined lavage fluid cytokine levels by enzyme-linked immunosorbent assay. In patients with beryllium disease (n = 23), we observed elevated macrophage mRNA expression for TNF-alpha and IL-6 when compared with that of normal subjects (n = 7). Sarcoidosis patients (n = 6) also had increased expression for TNF-alpha and IL-6 compared with that of normal volunteers. IL-1 beta expression was similar in all three groups. In patients with beryllium disease (n = 39), lavage fluid TNF-alpha concentration was higher than that of 16 normal subjects. Lavage fluid IL-1 beta and IL-6 levels did not differ among the groups. This is the first report of macrophage cytokine expression in beryllium disease. These novel findings suggest that macrophage expression of TNF-alpha and IL-6 may be important in the human granulomatous inflammatory response.

Cryptogenic organizing pneumonia: increased expression of interleukin-8 and fibronectin genes by alveolar macrophages.

Cryptogenic organizing pneumonia (COP) is a fibrotic process that primarily involves the alveolar spaces, alveolar ducts, and small conducting airways. The pathogenesis is not understood. Recent histopathologic studies have shown that during the cellular phase of COP, fibronectin deposits are present in the lung. Moreover, a neutrophil alveolitis is frequently seen in COP. Little is known about the involvement of alveolar macrophages in the pathogenesis of COP. However, alveolar macrophages are the principal resident cells in the airways, and they are thought to play a central role in the fibrotic process by virtue of their ability to express and release cytokines such as interleukin-8 (IL-8; a neutrophil chemotactic factor) and fibronectin (FN; a fibrogenic matrix-associated protein). We have quantified the spontaneous gene expression of IL-8 and FN by alveolar macrophages from five nonsmoking individuals with COP and compared them with 10 normal, healthy volunteers (five smokers, five nonsmokers). Expression of IL-8 and FN was measured by a quantitative assay employing reverse transcription of mRNA and the polymerase chain reaction. beta-actin mRNA expression was quantified as an internal standard, and the expression of FN and IL-8 transcripts was calculated as a ratio with beta-actin. The mean +/- SEM of the IL-8/beta-actin ratio in alveolar macrophages from patients with COP was 0.45 +/- 0.07, which was significantly higher than the level from either normal smokers (0.19 +/- 0.02, P = 0.008) or normal nonsmokers (0.16 +/- 0.01, P = 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)

Transforming growth factor-beta primes macrophages to express inflammatory gene products in response to particulate stimuli by an autocrine/paracrine mechanism.

Macrophages maintain an essential role in orchestrating the host inflammatory response by selectively mobilizing portions of their large secretory repertoire in response to phagocytic as well as other stimuli. For example, after exposure to the inflammatory particulate stimulus zymosan (or its derivative beta 1,3-glucan), monocyte/macrophages synthesize and release lysosomal hydrolases, mobilize arachadonic acid, and secrete cytokines such as TNF-alpha and IL-8. However, the mechanisms by which particulate stimuli promote the selective synthesis and release of macrophage-derived inflammatory gene products are unknown. Given the previously reported potential of transforming growth factor-beta (TGF-beta) as an important mediator of the inflammatory response in vivo, we investigated the role of TGF-beta in the regulation of particulate-induced macrophage inflammatory gene expression. We determined that TGF-beta primed macrophages to synthesize lysosomal hydrolases and express platelet-derived growth factor-B mRNA transcripts in response to both submaximal doses of beta 1,3-glucan and the nonspecific phagocytic stimulus latex particles, which by themselves did not induce expression of either inflammatory gene product. The endogenous production of active TGF-beta was shown to regulate inflammatory gene expression by demonstrating that: 1) beta 1,3-glucan stimulated both TGF-beta mRNA expression and protein release into conditioned media; 2) supernatants from stimulated macrophages primed for lysosomal hydrolase synthesis, and this effect was blocked by anti-TGF-beta antibodies; and 3) anti-TGF-antibodies blocked beta 1,3-glucan-stimulated lysosomal hydrolase synthesis. Collectively, these data describe a novel function for TGF-beta as a priming agent for macrophage inflammatory gene expression and suggest a mechanism for local amplification of the inflammatory response.

[Idiopathic subacute pulmonary eosinophilia]. / Pneumopathie éosinophilique subaiguë idiopathique.

We report a case of pneumonia with hypoxaemia and a swinging fever which was resistant to antibiotics, but was associated with a hypereosinophilia (44%) noted in the bronchoalveolar lavage. Investigations as to the cause of the eosinophilic pneumonia were negative; a lung biopsy confirmed the eosinophilic infiltration and the absence of any angiitis. There was a rapid and favourable clinical outcome following steroid therapy, which was maintained for three months. No relapse has been noted in the ten months of follow up since ceasing the cortico-steroids. The diagnosis appears to be that of a sub-acute, idiopathic eosinophilic pneumonia. The similarities and differences between this case and the chronic idiopathic eosinophilic pneumonia of Carrington were discussed.

Increased expression of the interleukin-8 gene by alveolar macrophages in idiopathic pulmonary fibrosis. A potential mechanism for the recruitment and activation of neutrophils in lung fibrosis.

Neutrophil migration into the airspaces of the lung is thought to contribute to the alveolar damage and subsequent fibrosis in idiopathic pulmonary fibrosis (IPF). Interleukin 8 (IL-8), a monocyte- and macrophage-derived cytokine, displays potent chemotactic and activating properties towards neutrophils and thus may contribute to the pathogenesis of IPF. The objective of this investigation was to quantify the spontaneous expression of IL-8 transcripts by alveolar macrophages from normal healthy volunteers and individuals with IPF. A quantitative assay employing reverse transcription of mRNA and the polymerase chain reaction was utilized. The level of IL-8 mRNA in alveolar macrophages was found to be significantly elevated in individuals with lone IPF or with lung fibrosis associated with connective tissue disorders compared to normal healthy controls. Moreover, the level of IL-8 mRNA in the 23 individuals with IPF correlated with the number of neutrophils per milliliter in their bronchoalveolar lavage (BAL) and with the degree of disease severity. In addition, the level of IL-8 protein in BAL was found to reflect the pattern of IL-8 mRNA expression by alveolar macrophages. These data suggest that IL-8 derived from alveolar macrophages may significantly contribute to neutrophil involvement in the pathogenesis of IPF.

The lavage fluid from a patient with alveolar proteinosis inhibits the in vitro chemiluminescence response and arachidonic acid metabolism of normal guinea pig alveolar macrophages.

Pulmonary alveolar proteinosis is characterized by the accumulation of a lipoproteinaceous material within the alveoli of the lung. It is well established that patients with pulmonary alveolar proteinosis have a high incidence of complicating pulmonary infections possibly resulting from defects of antibacterial functions of alveolar macrophages. Moreover, for unclear reasons, an inflammatory response in the airways is frequently absent. In order to investigate the role of the lipoproteinaceous material in these two patterns, we tested the in vitro effects of a lavage fluid from a human pulmonary alveolar proteinosis on the secretion of reactive oxygen intermediates and arachidonic acid metabolites by normal guinea pig alveolar macrophages. After incubation with the lipoproteinaceous material, the luminol-enhanced chemiluminescence of zymosan-triggered alveolar macrophages was reduced in a dose-dependent fashion. The lipoproteinaceous material similarly reduced the chemiluminescence response in a cell-free xanthine-xanthine oxidase system generating superoxide anions. This latter observation suggests that the lipoproteinaceous material acts as a scavenger for superoxide anions produced by alveolar macrophages. Its purified protein or phospholipid fractions also resulted in a general inhibition of the secretion of arachidonic acid metabolites by alveolar macrophages challenged in vitro with zymosan. Our results suggest that the alveolar filling material of pulmonary alveolar proteinosis may inhibit the action of antibacterial and/or proinflammatory agents produced by alveolar macrophages. We speculate that such effects of the lipoproteinaceous material may play a role in vivo in the high incidence of pulmonary infections and in the absence of discernible interstitial or intraalveolar inflammation seen in pulmonary alveolar proteinosis.

Amyotrophic lateral sclerosis presenting with sleep hypopnea syndrome.

Described is a 67-year-old man whose initial symptoms evoked an obesity-hypoventilation syndrome. Polysomnography showed hypopneas associated with O2 desaturation episodes, and no apnea; maximal changes were noted during REM sleep. A few months later, in spite of marked weight loss, acute alveolar hypoventilation occurred and necessitated mechanical ventilatory support. Tracheostomy was performed. The patient appeared to be dependent on nocturnal ventilatory assistance. Diaphragmatic paralysis was noted in addition to clinical and electrodiagnostic evidence of amyotrophic lateral sclerosis. While the patient was not ventilated, a nocturnal recording of SaO2 again revealed desaturation episodes partly corrected by O2 2 L/min administered through the tracheostomy tube. With volume-controlled ventilation, desaturations completely disappeared, although no oxygen enrichment of the air was provided. We speculate that sleep disorders with hypopneas and O2 desaturation episodes were the initial symptoms of amyotrophic lateral sclerosis. This leads us to suggest that nonspecific respiratory muscle fatigue frequently seen in COPD might be included in the hypothetic causes of nocturnal hypoxemia.