[Which physical tests for which objectives in pulmonary rehabilitation?]

Chronic respiratory disease is a major cause of morbidity and mortality worldwide and an important cause of disability including a reduction of exercise, functional and muscle capacity contributing to a decreased quality of life. In the context of pulmonary rehabilitation, a thorough patient-centered outcome assessment, including not only measures of lung function, but also exercise functional and muscle capacity, is imperative for a comprehensive disease management. Assessment of these impairments and dysfunctions with appropriate and change-sensitive procedures is thus necessary for personalizing the physical interventions and assessing the short- and long-term effectiveness of the intervention. The clinician currently has a wide variety of tests and measurements available to assess the physical and functional capacity of people with chronic respiratory disease. The aim of this review is to provide a pragmatic synthesis of the physical, functional and muscle capacity tests most commonly used in pulmonary rehabilitation. Ultimately, it should help the clinician to identify the relevant evaluations according to the objectives of the patients but also according to the available resources, the setting of pulmonary rehabilitation and the specific qualities of each test.

[Malt lung lymphoma]

MALT lung lymphoma is a low-grade primarily B-cell lymphoma. Most cases develop in a pain free patient presenting a chronic alveolar opacity. In this review, we describe the clinical radiological and pathological features as well as the diagnostic approach to this pathological entity. Prognosis is excellent. Therapeutic options are discussed.

[Bronchopulmonary aspergillosis infections in the non-immunocompromised patient]

The definition of broncho-pulmonary aspergillosis infections in non-immunocompromised patients remains vague and a wide range of clinical, radiological and pathological entities have been described with a variety of names, i.e. simple aspergilloma, complex aspergilloma, semi-invasive aspergillosis, chronic necrotizing pulmonary aspergillosis, chronic cavitary and fibrosing pulmonary and pleural aspergillosis, pseudomembranous tracheobronchitis caused by Aspergillus, and invasive aspergillosis. However, these disease entities share common characteristics suggesting that they belong to the same group of pulmonary aspergillosis infectious disorders: 1- a specific diathesis responsible for the deterioration in local or systemic defenses against infection (alcohol, tobacco abuse, or diabetes); 2- an underlying bronchopulmonary disease responsible or not for the presence of a residual pleural or bronchopulmonary cavity (active tuberculosis or tuberculosis sequelae, bronchial dilatation, sarcoidosis, COPD); 3- generally, the prolonged use of low-dose oral or inhaled corticosteroids and 4- little or no vascular invasion, a granulomatous reaction and a low tendency for metastasis. There are no established treatment guidelines for broncho-pulmonary aspergillosis infection in non-immunocompromised patients, except for invasive aspergillosis. Bronchial artery embolization may stop hemoptysis in certain cases. Surgery is generally impossible because of impaired respiratory function or the severity of the comorbidity and when it is possible morbidity and mortality are very high. Numerous clinical cases and short retrospective series have reported the effect over time of the various antifungal agents available. Oral triazoles, i.e. itraconazole, and in particular voriconazole, appear to provide suitable treatment for broncho-pulmonary aspergillosis infections in non-immunocompromised patients.

[Cardiorespiratory limits to the surgical treatment of lung cancer]

Cardiorespiratory co-morbidity is a predictive factor of post-surgical mortality and morbidity. In the case of lung cancer, the pre-therapeutic work-up must assess the post-surgical risks by integrating such co-morbidity. In view of this, predictive scores and decisional algorithms have been developed. However, such tools were developed and assessed only to predict post-surgical risks during the first or second month following resection. Till now, prediction of long term quality of candidates for pulmonary resection has not be studied, although the question has often been raised by the patient and the medical and surgical teams, notably in the case of cardiorespiratory limitation prior to the intervention. A study on the predictability of the quality of life at 6 months following pulmonary resection was conducted in the Tenon hospital in a cohort of 81 patients, candidates for resection, initially selected on an MMFR lesser than 80% of the reference. Out of the 43 patients who finally underwent resection and were analysed at 6 months, there were few predictive factors for the alteration in quality of life at 6 months following pulmonary resection, other than the extension of the surgical act. Conversely, this alteration did not significantly depend on the immediate post-surgical events and can be explained by the deterioration in respiratory function.

Upregulation of bronchioloalveolar carcinoma-derived C-X-C chemokines by tumor infiltrating inflammatory cells

OBJECTIVE AND DESIGN

The presence of increased numbers of tumor-infiltrating neutrophils is associated with poorer outcome in patients with adenocarcinoma of the bronchioloalveolar (BAC) subtype. We evaluated the role of inflammatory environment on C-X-C chemokine tumor production.

MATERIALS

Bronchoalveolar lavage from 31 consecutive patients with adenocarcinoma of the BAC subtype as well as tumor and normal pulmonary tissue samples. A549 BAC cell line. Peripheral blood mononuclear cells (PBMC), polymorphonuclear neutrophils (PMN) and alveolar macrophages (AM).

METHODS

Elisa measurements and immunohistochemical studies of ENA-78, IL-8, IL-1beta and TNF-alpha. RNA isolation, reverse transcription, and PCR amplification of ENA-78 and IL-8.

RESULTS

C-X-C peptides were expressed by tumor cells of all the tumor specimens tested. ENA-78 and IL-8 were also expressed by AM. To better understand the regulation of the C-X-C production, BAC cell line was cultured alone or with inflammatory cells. PBMC upregulated both tumor ENA-78 and IL-8 mRNA expression and protein release whereas AM only upregulated ENA-78 mRNA expression and protein release; PMN had no effect. Anti-human IL-1beta antibodies (ab) inhibited the A549 ENA-78 and IL-8 production stimulated by PBMC-CM. Anti-human TNF-alpha ab inhibited A549 ENA-78 production stimulated by AM-CM. IL-1beta and TNF-alpha were expressed in vivo by inflammatory cells, although TNF-alpha was also expressed by tumor cells.

CONCLUSIONS

This work emphasizes the role of the host inflammatory response in promoting tumor growth in vivo.

Transforming growth factor-beta inhibits interleukin-10 synthesis by human monocytic cells

Transforming growth factor-beta (TGF-beta1) enhances interleukin-10 (IL-10) synthesis by mouse monocytes/macrophages, suggesting a potential role of IL-10 in mediating some of the anti-inflammatory properties of TGF-beta1. Since differences exist between the transcriptional regulation of human and mouse IL-10, the studies reported here examined whether TGF-beta1 up-regulated IL-10 production by human monocytes/macrophages as well. Exposure of PMA-differentiated U-937 promonocytic cells to TGF-beta1 resulted in an unexpected, dose-dependent decrease in IL-10 production as assessed by specific ELISA. TGF-beta1 was effective when added at the time of the PMA stimulus or 6 hours after. In addition, TGF-beta1 suppressed induction of IL-10 by three different stimuli other than PMA. TGF-beta1 inhibition of IL-10 protein release was associated with proportional changes in IL-10 mRNA accumulation as assessed by quantitative kinetic ELISA PCR. This would result from a decrease in IL-10 gene transcription as TGF-beta1 did not affect IL-10 mRNA stability, and TGF-beta1 limited the luciferase activity in cells transfected with reporter gene constructs containing 1,308 bp of the 5' non-coding sequence of human IL-10 gene. Blocking tumour necrosis factor-alpha (TNF-alpha) with neutralizing anti-TNF-alpha antibody did not modify the response to TGF-beta1, indicating the involvement of TNF-alpha-independent mechanisms in the overall process. Thus, the present study provides the first evidence that TGF-beta1 prevents IL-10 production by human monocytic cells at a transcriptional level.

Cytokines and hormones with anti-inflammatory effects: new tools for therapeutic intervention

The inflammation that is involved in the development of glomerulonephritis is tightly regulated by the expression of anti-inflammatory factors. These include circulating hormones, such as glucocorticoids, and mediators that are produced by intrinsic cells and infiltrating leucocytes. The present review focuses on these anti-inflammatory factors, summarizing in particular their activities in existing models of glomerulonephritis. In addition, experimental evidence is presented that anti-inflammatory mediators are able to increase glucocorticoid binding or signalling in target cells. These data help to explain the in-vivo efficacy of anti-inflammatory mediators, and offer a promising new avenue for therapeutic intervention.

[Interactions between glucocorticoids and anti-inflammatory peptides]

Both pro- and anti-inflammatory mediators regulate the anti-inflammatory actions of glucocorticoids, in part by modifying the binding of glucocorticoids to specific receptors. For instance, somatostatin has been shown to increase glucocorticoid binding and signaling in macrophages. The mechanism of this regulation does not require an increased expression of glucocorticoid receptors but, rather, a stabilization of glucocorticoid receptor-associated heat shock protein 90. This is related to a decrease in calpain activity. Thus calpain inhibition may offer a new and exciting possibility for enhancing the anti-inflammatory efficiency of glucocorticoids.

Somatostatin increases glucocorticoid binding and signaling in macrophages by blocking the calpain-specific cleavage of Hsp 90

Somatostatin has direct anti-inflammatory actions and participates in the anti-inflammatory actions of glucocorticoids, but the mechanisms underlying this regulation remain poorly understood. The objective of this study was to evaluate whether somatostatin increases glucocorticoid responsiveness by up-regulating glucocorticoid receptor (GR) expression and signaling. Somatostatin promoted a time- and dose-dependent increase in [(3)H]dexamethasone binding to RAW 264.7 macrophages. Cell exposure to 10 nM somatostatin for 18 h promoted a 2-fold increase in the number of GR sites per cell without significant modification of the affinity. Analysis of GR heterocomplex components demonstrated that somatostatin increased the level of heat shock protein (Hsp) 90, whereas the level of GR remained almost unchanged. The increase in Hsp 90 was associated with a decrease in the cleavage of its carboxyl-terminal domain. Evidence for the involvement of calpain inhibition in this process was obtained by the demonstration that 1) somatostatin induced a dose-dependent decrease in calpain activity and 2) calpain inhibitors, calpain inhibitor I and calpeptin, both abolished the cleavage of Hsp 90 and induced a dose-dependent increase in [(3)H]dexamethasone binding. Increases in glucocorticoid binding after somatostatin treatment were associated with similar increases in the ability of GR to transactivate a minimal promoter containing two glucocorticoid response elements (GRE) and to interfere with the activation of nuclear factor-kappaB (NF-kappaB). Thus, the present findings indicate that somatostatin increases glucocorticoid binding and signaling by limiting the calpain-specific cleavage of GR-associated Hsp 90. This mechanism may represent a novel target for intervention to increase glucocorticoid responsiveness.

[Severe acute asthma in the emergency room: amelioration of decreased peak flow rate is interpreted with difficulty]

We report a severe acute asthma case whose course was marked by persistent hypoxemia whereas proximal flows were normalized. This discordance reveals a ventilation/perfusion mismatch. This data suggests that care must be taken in interpreting the peak flow improvement during acute severe asthma management.

Reactive oxygen and nitrogen intermediates increase transforming growth factor-beta1 release from human epithelial alveolar cells through two different mechanisms

Transforming growth factor (TGF)-beta1 is a growth factor involved in the mechanisms of lung repair and fibrosis that follow inflammatory processes. We sought to examine the link between the generation of reactive oxygen intermediates (ROI) or reactive nitrogen intermediates (RNI) by inflammatory cells and the expression of TGF-beta1 by alveolar epithelial cells. Exposure of the A549 lung epithelial cell line to either an ROI generating system (xanthine and xanthine oxidase) or an RNI donor (S-nitroso-N-acetyl-penicillamine [SNAP]) promoted a time- and dose-dependent increase in TGF-beta1 release, as measured by a specific enzyme-linked immunosorbent assay. At the peak, the levels of TGF-beta1 were twice the control values. The induction of TGF-beta1 release by ROI was blunted by catalase and unaffected by superoxide dismutase, indicating the involvement of hydrogen peroxide. The response was also blunted by 5, 6-dichloro-1-beta-D-ribofuranosyl benzimidazole (DRB), a specific RNA polymerase II inhibitor, and accompanied by a corresponding increase in TGF-beta1 messenger RNA, as measured by quantitative/competitive reverse transcription polymerase chain reaction, suggesting the involvement of transcriptional mechanisms and possibly other downstream mechanisms. In contrast, RNI-induced TGF-beta1 release was unaffected by DRB and blunted by the protein synthesis inhibitor cycloheximide, suggesting the involvement of translational and post-translational mechanisms. This response required cyclic guanosine monophosphate (cGMP)- mediated processes because (1) immunoreactive cGMP accumulated in the culture medium of SNAP-treated cells; (2) SNAP-induced TGF-beta1 release was blunted by KT 5823, an inhibitor of cGMP-dependent protein kinase; and (3) similar increase in TGF-beta1 release was obtained by cell exposure to membrane-permeable dibutyryl-cGMP or to atrial natriuretic factor, a known agonist of particulate guanylate cyclase. These data suggest that in vitro exposure of human alveolar epithelial cells to ROI and RNI enhances TGF-beta1 release through different mechanisms. In vivo, this control may constitute a molecular link between inflammatory and fibrotic processes.

[Inflammatory mechanisms of renal fibrosis: glomerulonephritis]

Studies of glomerulonephritis models have shown that inflammatory reaction is responsible for the development of glomerulosclerosis and tubulo-interstitial sclerosis and, hence, for the progression to end stage renal failure. That macrophage accumulation and fibrosis extension are frequently not closely related events suggests that macrophages are not involved in progression process. Glomerular sclerosis is rather associated with the release of mediators from resident cells-mainly growth factors such as platelet-derived growth factor and transforming growth factor-beta--the synthesis and bioactivity of which are enhanced by inflammatory mediators. Tubulo-interstitial sclerosis is induced by inflammatory lesions of the glomerulus that lead to proteinuria. Indeed, reabsorption of proteins in proximal tubule triggers epithelial cells to release proinflammatory and prosclerotic mediators into the interstitium. New therapeutic approaches including gene transfer strategies are directed at suppressing the efficiency of such mediators.

Reduction of tumour necrosis factor alpha expression and signalling in peripheral blood mononuclear cells from patients with thalassaemia or sickle cell anaemia upon treatment with desferrioxamine

Recent evidence indicates that the rate of progression of the HIV-1 disease is significantly reduced in thalassaemia major patients upon treatment with high doses of desferrioxamine (DFX). The authors have previously demonstrated that in vitro exposure of mononuclear cells to DFX decreases the bioavailability of tumour necrosis factor alpha (TNF-alpha) which has a stimulatory effect on HIV-1 replication. In this study, therefore, TNF-alpha bioavailability from mononuclear cells isolated from 10 patients with thalassaemia or sickle cell anaemia given DFX as compared to 10 untreated subjects has been evaluated. Evidence is presented showing that DFX treatment reduces TNF-alpha bioavailability (P<0.05) by inhibiting its steady state (P<0.05) and by enhancing its inactivation through binding to soluble TNF-alpha receptor type II (P<0.05). We also show that DFX treatment limits the in vivo activation of NF-kappaB, a transcription factor involved in both TNF-alpha gene transcription and TNF-alpha signalling (P<0.005). We conclude that TNF-alpha bioavailability and signalling are impaired in patients upon DFX treatment. This mechanism may contribute to delayed progression of the HIV-1 infection in vivo.

Growth hormone and somatostatin in glomerular injury

Among other neuropeptides and neurohormones, growth hormone (GH) and somatostatin (SRIF) have been shown to modulate the development of glomerular injury in various renal diseases. In particular, GH is implicated in the induction of glomerular hypertrophy and sclerosis in partial nephrectomy and diabetic nephropathy. While GH effects on glomerular hypertrophy are likely mediated by insulin-like growth factor I (IGF-I), GH effects on glomerular sclerosis are independent of IGF-I. Those effects rather require multiple signaling pathways functioning in series, e.g. angiotensin II binding preceding transforming growth factor beta (TGF-beta) release, or pro-inflammatory factor release preceding repair/scarring processes. In contrast with GH, SRIF administration prevents the development of glomerular lesions in experimental diabetes, partial nephrectomy and immune glomerulonephritis. Inhibitory effects of SRIF on glomerular hypotrophy may be through a decrease in GH secretion and/or IGF-I expression or through a direct blockade of glomerular cell proliferation. The mechanisms underlying the anti-inflammatory effects of SRIF are most likely a deactivation of inflammatory cells related in part to an upregulated response of these cells to glucocorticoids. Additional studies will be required to further define the role of GH and SRIF in the development of glomerular injury and, hence, to identify new targets for a therapeutic approach in glomerular diseases.

Low environmental pH is responsible for the induction of nitric-oxide synthase in macrophages. Evidence for involvement of nuclear factor-kappaB activation

Stimulation of macrophages with endotoxin and/or cytokines is responsible for the expression of the inducible isoform of nitric oxide synthase (iNOS). Because macrophages are exposed to low pH within the microenvironment of inflammatory lesions, the potential role of acidic pH as an additional regulator of iNOS was investigated. Substitution of the culture medium of rat peritoneal macrophages at pH 7.4 with medium at pH 7.0 up-regulated iNOS activity, as reflected by a 2.5-fold increase in nitrite accumulation. The increase in iNOS activity was associated with a similar increase in iNOS mRNA expression that reflected an increase in iNOS mRNA synthesis rather than stability. Low environmental pH-induced iNOS gene transcription involved the activation of nuclear factor-kappaB (NF-kappaB) transcription factor since exposure of macrophages to low environmental pH both increased NF-kappaB binding activity in the nucleus and enhanced NF-kappaB-driven reporter gene expression. In addition, treatment of macrophages with pyrrolidine dithiocarbamate or n-acetyl-leucinyl-leucinyl-norleucinal, two drugs preventing NF-kappaB translocation to the nucleus, canceled low pH-induced nitrite accumulation. The overall mechanism required the synthesis of tumor necrosis factor alpha (TNFalpha). Indeed, 1) elevated TNFalpha bioactivity was observed in the medium of macrophages exposed to pH 7.0, and 2) incubation of macrophages with a neutralizing anti-TNFalpha antibody impaired both NF-kappaB activation and nitrite accumulation in response to acid challenge. In summary, exposure of macrophages to acidic microenvironment in inflammatory lesions leads to the up-regulation of iNOS activity through the activation of NF-kappaB.

Neutrophil alveolitis in bronchioloalveolar carcinoma: induction by tumor-derived interleukin-8 and relation to clinical outcome

Tumor infiltrate, predominantly constituted by lymphocytes, may represent an important prognostic factor in bronchioloalveolar carcinoma (BAC), in addition to tumor extension and histological type. In the present study, we determined the presence, the origin, and the prognostic importance of neutrophils that also participate in leukocyte infiltrates of BAC. Neutrophil alveolitis was determined immunohistochemically in both lung biopsies and bronchoalveolar lavage (BAL) fluid samples from 29 patients with histologically proved BAC. The local expression of interleukin (IL)-8 was determined by immunohistochemical and immunoenzymatic techniques. Neutrophil counts were analyzed in relation to the clinical outcome of patients by the Kaplan-Meier method and Cox's univariate and stepwise multivariate models. Lymphocytes and neutrophils dominated the inflammatory cell population in the lower respiratory tract of patients with BAC. Neutrophils were located mainly in the alveolar lumen and seldom in alveolar wall whereas lymphocytes were exclusively present in alveolar wall. A relationship was observed between the number of neutrophils and the level of IL-8 in BAL fluid suggesting the involvement of that chemokine in neutrophil recruitment. The tumor cells were the predominant cells that appeared to express IL-8 by immunolocalization. The presence of increased numbers of neutrophils was significantly associated with a poorer outcome in patients with BAC (P = 0.02). In a multivariate analysis, the neutrophil percentage in BAL fluid was an independent predictor of clinical outcome. The risk of death was increased substantially (rate ratio, 5.2; 95% confidence interval, 1.1 to 24.7) among patients with BAL neutrophil percentage of > or = 39% (median of the distribution) as compared with the others. In BAC, neutrophils accumulate in the alveolar lumen. Elaboration of IL-8 by tumor cells may be responsible for this event, which is associated with a significantly higher risk of death.

Insulin-like growth factors and their binding proteins in pleural fluid

We investigated the expression and potential regulatory role of insulin-like growth factors (IGFs) and their specific binding proteins (BPs) in tuberculous and nontuberculous pleuritis. By using a radioimmunoassay after acid gel filtration chromatography, we found that mean concentrations of IGF-I were 211.9 +/- 20.2 microg/l and 203.2 +/- 31.1 microg/l in pleural fluid of 14 patients with tuberculous pleuritis and 9 patients with malignant pleuritis respectively. These values were near those in serum of the same patients (221.3 +/- 19.5 microg/l and 204.6 +/- 21.0 microg/l respectively). By using a specific protein-binding assay, we found that mean concentrations of IGF-II were 345.3 +/- 61.0 microg/l and 167.6 +/- 22.7 microg/l in tuberculous and malignant pleural effusions respectively. These values were significantly lower than those in serum of the same patients (628.3 +/- 79.0 microg/l, P<0.025 and 532.0 +/- 85.9 microg/l, P<0.025 respectively). Because bioavailability and bioactivity of IGFs may be regulated by their binding to IGFBPs, we studied IGFBP patterns in the pleural fluid of 6 patients with tuberculous pleuritis. As assessed by Western ligand blotting the levels of IGFBP-1 and IGFBP-2 were increased whereas those of IGFBP-3 were decreased in pleural fluid in comparison with serum. The decrease in IGFPB-3 levels reflected increased proteolysis, as assessed by Western immunoblotting. In spite of this presence of IGFBPs, IGFs could be responsible for the local biosynthesis of 1.25-dihydroxyvitamin D (1,25-(OH)2D) since pleural fluid levels of both IGF-I and IGF-II significantly correlated with those of 1,25-(OH)2D. These results indicate that IGFs are detectable in pleural fluid and may contribute to control the activity of 25-hydroxyvitamin D-1alpha hydroxylase in tuberculous pleuritis.

[Primary pulmonary lymphoma]

There are three distinct clinico-anatomical entities today covered by the definition of a primary clonal pulmonary lymphoid proliferation. These are pulmonary lymphomas of B cell phenotype, of low grade malignancy, B cell lymphomas of high grade malignancy and finally lymphomatoid granulomatosis whose clonal characteristic is sometimes difficult to confirm. This general review aims to specify the pathophysiological, diagnostic, prognostic and therapeutic aspects of these different types. Low grade B cell lymphoma is the most common pulmonary lymphoma. Their development depends on mucosa associated lymphoid tissue. They are most often indolent and present as a chronic alveolar opacity. Their prognosis is excellent and the modalities of treatment are discussed (no therapy, surgery or monochemotherapy). High grade B cell pulmonary lymphomas are much rarer and may result from the transformation of a low grade lymphoma or arise in a particular situation such as imunodepression. Their prognosis is poor and the therapeutic possibilities depend most often on the underlying disease. The presence of lymphomatoid granulomatosis in this group of pulmonary lymphomas is debatable. The demonstration of a clonal character of this proliferation is practically never obtained and there is often extra pulmonary disease. The prognosis of this type of illness is extremely variable because certain studies have shown a cure using corticosteroids and cyclophosphamide whilst others have found that the disease is always fatal in spite of using strong polychemotherapy.

[Low extracellular pH has a role in the induction of NO synthase type 2 in macrophages]

Stimulation of macrophages with endotoxin and/or cytokines is responsible for the expression of the inducible isoform of nitric oxide synthase (iNOS). Because macrophages are exposed to low pH within the microenvironment of inflammatory lesions, the potential role of low pH as an additional regulator of iNOS was investigated. Substitution of the culture medium of rat peritoneal macrophages at pH 7.4 with medium at pH 7.0 upregulated iNOS activity, as reflected by a 2.5-fold increase in nitrite accumulation. The increase in iNOS activity was associated with a similar increase in iNOS mRNA expression. Low environmental pH-induced iNOS gene expression involved the activation of nuclear factor-kappa B (NF-kappa B) transcription factor since [1] exposure of macrophages to low environmental pH increased NF-kappa B binding activity in the nucleus, and [2] treatment of macrophages with pyrrolidine dithiocarbamate or n-acetyl-leucinyl-norleucinal, two drugs preventing NF-kappa B translocation to the nucleus, canceled low pH-induced nitrite accumulation. The overall mechanism required the synthesis of tumor necrosis factor-alpha (TNF-alpha). Indeed, [1] elevated TNF-alpha bioactivity was observed in the medium of macrophages exposed to pH 7.0, and [2] incubation of macrophages with a neutralizing anti-TNF-alpha antibody impaired both NF-kappa B activation and nitrite accumulation in response to acid challenge. In summary, exposure of macrophages to acidic microenvironment in inflammatory lesions leads to the upregulation of iNOS activity through the activation of NF-kappa B.

Regulation of interleukin-10 production by beta-adrenergic agonists

Catecholamines have been shown to inhibit some aspects of macrophage activation through a beta receptor-dependent mechanism. This study was undertaken to analyze the effects of isoproterenol, a specific beta-adrenergic agonist, on the synthesis of interleukin-10 (IL-10), a major macrophage-deactivating factor. Isoproterenol increased IL-10 release from lipopolysaccharide-(LPS)-activated mouse peritoneal macrophages in a dose-dependent manner. A significant effect was already observed with 1 microM isoproterenol, while a 4.5-fold increase was achieved with 10 microM. This increase was observed only if macrophages were exposed to isoproterenol for at least 2 h before LPS challenge. It was apparent within 0.5 h and persisted through 24 h at all the LPS concentrations used. A similar increase was observed at the IL-10 mRNA level, as judged by enzyme-linked immunosorbent assay-polymerase chain reaction. The macrophage response to isoproterenol that led to cyclic AMP accumulation was markedly inhibited by H-89, a potent inhibitor of protein kinase A. These data suggest the involvement of cyclic AMP in the regulation of IL-10 synthesis by isoproterenol. IL-10 was in turn partly responsible for a reduction in tumor necrosis factor-alpha synthesis. In vivo, the administration of oxprenolol, a beta-receptor antagonist, significantly reduced serum IL-10 levels 90 min after LPS challenge. Thus, the present study provides the first evidence that endogenous catecholamines are of critical importance in determining the magnitude of the IL-10 response in experimental endotoxemia.

[From pseudolymphomas to primary pulmonary lymphomas of MALT type]

Primary lung lymphomas are uncommon and the use of immunohistochemical and molecular biological techniques have widely contributed to their understanding. Generally, they are of low grade malignancy and most develop from mucosa-associated lumphoid tissue (MALT). Cellular analyses of samples obtained routinely by endoscopy (transbronchial biopsy or bronchoalveolar lavage) will probably enable the clinician to avoid invasive diagnostic procedures, such as surgical lung biopsy. Treatment of limited forms is usually surgical. As to bilateral forms or those with lesions of other mucosae e.g. gut, the best therapeutic strategy remains to be defined.

Activation of T cells by previously activated T cells. HLA-unrestricted alternative pathway that modifies their proliferative potential

When cultured in the presence of previously activated T cells, up to 30% of resting T cells are activated, as indicated by lymphoblastic morphology, formation of cell aggregates, expression of activation Ags (CD25 and HLA-DR), and a proliferative response. This activation occurred in the absence of accessory cells and was not HLA restricted, and the TCR repertoire of the responding cells was extremely diverse without evidence for preferential expansion of T cells expressing certain V beta families or clonal populations. The ability of activated T cells to stimulate resting T cells was a transient phenomenon, which was first detected 24 h after activation and which peaked between 48 and 96 h; the stimulation of previously resting T cells produced more lymphostimulatory activity than restimulation of recently activated cells. Both resting CD4+ and CD8+ T cells expressing TCR-alpha beta and -gamma delta responded to previously activated cells, including cells with both the naive and memory phenotypes. When T cells were activated by this pathway and recultured in the presence of Ag and accessory cells, the strong proliferative response observed at 5 to 7 days with use of fresh T cells was almost entirely absent, and this impaired Ag-induced proliferative response could not be explained by the generation of suppressor cells or the inability of these cells to respond to growth factors. These findings are compatible with the possibility that Ag-specific activation of T cells permits the subsequent Ag-independent activation of other T cells and could explain the broad TCR repertoire and impaired Ag-induced proliferation of activated T cells at sites of immune reactions.

Activation of T cells by previously activated T cells. HLA-unrestricted alternative pathway that modifies their proliferative potential

When cultured in the presence of previously activated T cells, up to 30% of resting T cells are activated, as indicated by lymphoblastic morphology, formation of cell aggregates, expression of activation Ags (CD25 and HLA-DR), and a proliferative response. This activation occurred in the absence of accessory cells and was not HLA restricted, and the TCR repertoire of the responding cells was extremely diverse without evidence for preferential expansion of T cells expressing certain V beta families or clonal populations. The ability of activated T cells to stimulate resting T cells was a transient phenomenon, which was first detected 24 h after activation and which peaked between 48 and 96 h; the stimulation of previously resting T cells produced more lymphostimulatory activity than restimulation of recently activated cells. Both resting CD4+ and CD8+ T cells expressing TCR-alpha beta and -gamma delta responded to previously activated cells, including cells with both the naive and memory phenotypes. When T cells were activated by this pathway and recultured in the presence of Ag and accessory cells, the strong proliferative response observed at 5 to 7 days with use of fresh T cells was almost entirely absent, and this impaired Ag-induced proliferative response could not be explained by the generation of suppressor cells or the inability of these cells to respond to growth factors. These findings are compatible with the possibility that Ag-specific activation of T cells permits the subsequent Ag-independent activation of other T cells and could explain the broad TCR repertoire and impaired Ag-induced proliferation of activated T cells at sites of immune reactions.

T cell receptor repertoire of T lymphocytes recovered from the lung and blood of patients with sarcoidosis

We evaluated the repertoire of V beta segments used in forming the T-cell receptor of lavage and blood T lymphocytes from 11 sarcoid patients and 10 normal subjects using procedures based on quantitative polymerase chain reaction, permitting analysis of both the abundance of transcripts using each of 20 different V beta families and the diversity of the VDJC beta rearrangements within each V beta family. Blood and lung T cells from sarcoid patients had a very diverse V beta repertoire. For all V beta families but one, the abundance of the V beta transcripts fell within the mean +/- 2 SD of that observed for normal blood lymphocytes; no difference in the overall abundance was observed comparing lavage and blood T cells, and the length of VDJC beta rearrangements for a given V beta family in samples from sarcoid patients was usually quite heterogeneous. Despite the overall polyclonality, evidence for selective expansion of T cells was found, in that an increased abundance of V beta 19 transcripts was observed for sarcoid blood and/or lung T cells in eight out of 11 patients studied, and rearrangements of a single predominant length using certain (e.g., V beta 19, V beta 14), but not all, V beta families were present. Sequencing confirmed the presence of a single predominant VDJC beta rearrangement in these cases. These findings suggest that the alveolitis in sarcoidosis results from two distinct processes, a local clonal expansion of T cells associated with an apparently nonspecific accumulation of T cells with an extremely diverse V beta repertoire.

[Pulmonary hypertension: a rare complication of hepatic cirrhosis]

Pulmonary hypertension is a rare pulmonary complication of chronic hepatic diseases. Anatomopathologic and clinic data are very similar to primary pulmonary hypertension. Although the lesions of arteriopathy are more related to portal hypertension than to hepatic lesions, the physiopathology of this morbid association is unknown.