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Claire Danel

Publications and source records attributed to Claire Danel.

36 records · Page 2Linked to original sources
PubMed2004

Lactosylated polyethylenimine for gene transfer into airway epithelial cells: role of the sugar moiety in cell delivery and intracellular trafficking of the complexes.

BACKGROUND: As we have previously shown that lactosylated polyethylenimine (PEI) is the most efficient glycosylated PEI for gene transfer into human airway epithelial cells in primary culture, we have studied here the role of the lactose residue in the enhancement of gene transfer efficiency observed with lactosylated PEI as compared with unsubstituted PEI in immortalized (Sigma CFTE29o- cells) and primary human airway epithelial cells. METHODS AND RESULTS: After three transfections of 1 h performed daily, 60% of Sigma CFTE29o- cells were transfected with lactosylated PEI, whereas 25% of cells were transfected with unsubstituted PEI (p < 0.05). Cell viability was 1.8-fold greater with lactosylated PEI as compared with unsubstituted PEI (p < 0.05). As assessed by flow cytometry, the cellular uptake of lactosylated complexes was greater than that of complexes made with unsubstituted PEI (p < 0.05) and involved mostly a receptor-mediated endocytosis. The study of the intracellular trafficking in airway epithelial cells of complexes showed an endosomal and lysosomal accumulation of lactosylated complexes. In the presence of a proton pump inhibitor, the level of lactosylated and unsubstituted PEI-mediated gene expression was reduced more than 20-fold, whereas the cell viability increased to almost 100%. For both complexes, a nuclear localization was observed for less than 5% of intracellular complexes. CONCLUSIONS: Our results show that the greater gene transfer efficiency observed for lactosylated complexes may be attributed to a higher amount of lactosylated complexes incorporated by airway epithelial cells and a lower cytotoxicity that might be related to reduced endosomolytic properties. However, the lactose residues substituting the PEI did not promote the entry of the plasmid into the nucleus.

Biological Transport↗
PubMed2004

Peripheral intrapulmonary lymph node metastases of non-small-cell lung cancer.

Since the development and progress of computed tomographic imaging, peripheral intrapulmonary lymph nodes (IPLNs) have become increasingly described and well-known entities. Intrapulmonary lymph nodes may appear as a solitary pulmonary nodular shadow mimicking a non-small-cell lung cancer (NSCLC) or as multiple nodules masquerading as carcinoma metastases. We describe a case in which IPLNs presented as a clinical "nodular" T4 N0 NSCLC that finally proved to be a pathologic T2 N1 NSCLC, thus raising new questions on this entity.

Carcinoma, Non-Small-Cell Lung↗
PubMed2004

[Guidelines for the macroscopic studies of surgically resected lung specimens. Proposal for a anatomo-pathologic standardized form for the examination of pulmonary cancer].

We present practice guidelines for the examination of lung specimens removed for cancer, and pulmonary biopsies performed for interstitial lung diseases. In addition, we propose a standardized form for the reporting of lung cancer. This approach takes place in looking for better quality and should facilitate the use of the morphologic data, particularly in multicentric studies.

Biopsy↗
PubMed2003

Response of human pulmonary epithelial cells to lipopolysaccharide involves Toll-like receptor 4 (TLR4)-dependent signaling pathways: evidence for an intracellular compartmentalization of TLR4.

Pulmonary epithelial cells are continuously exposed to microbial challenges as a result of breathing. It is recognized that immune myeloid cells express Toll-like receptors (TLRs), which play a major role in detecting microbes and initiating innate immune responses. In contrast, little is known concerning the expression of TLR in pulmonary epithelial cells per se, their distribution within the cell, their function, and the signaling pathways involved. In this work, we demonstrated by reverse transcription-PCR and/or immunoblot that TLR4 and the accessory molecule MD-2 are constitutively expressed in distinct human alveolar and bronchial epithelial cells. We further characterized by flow cytometry, biotinylation/precipitation, and confocal microscopy the intracellular localization of TLR4 in these cells. Despite this intracellular compartmentalization of TLR4, pulmonary epithelial cells were responsive to the TLR4 activator lipopolysaccharide (LPS), a potent Gram-negative bacteria-associated molecular pattern. Using respiratory epithelial cells isolated from TLR4 knock-out and wild type mice, we demonstrated that TLR4 is the actual activating receptor for LPS in these cells. Furthermore we showed that this cell response to LPS involves a signaling complex including the kinases interleukin-1 receptor-associated kinase (IRAK), p38, Jnk, and ERK1/2. Moreover, using vectors expressing dominant-negative forms of MyD88 and TRAF6, we established that LPS-induced activation of respiratory epithelial cells is largely dependent on TLR4 signaling intermediates. Altogether these data demonstrate that TLR4 is a key element in the response of pulmonary epithelial cells to molecules derived from Gram-negative bacteria. The intracellular localization of TLR4 in lung epithelia is expected to play an important role in the prevention of the development of chronic inflammatory disease.

Cell Compartmentation↗
PubMed2003

In vivo selective and distant killing of cancer cells using adenovirus-mediated decorin gene transfer.

Decorin is a well-known, ubiquitous proteoglycan that is a normal component of the ECM. Upon transgenic expression of decorin, tumor cells with diverse histogenetic background overexpress p21WAF1, a potent inhibitor of cyclin-dependent kinase activity, become arrested in G1, and fail to generate tumors in immunocompromised animals. Because decorin is a secreted protein, it has been recently suggested that decorin could act as an autocrine and paracrine regulator of tumor growth. Here, we demonstrate that adenovirus (Ad)-mediated transfer and expression of human decorin cDNA induced in vivo apoptosis of xenograft tumor cells in nude mice. This oncolytic activity was observed when the Ad vector encoding the decorin cDNA was injected intratumorally (i.t.) or i.v. Importantly, i.t. injection of the decorin Ad vector led to growth inhibition of the injected tumor associated with similar growth inhibition of a distant contralateral tumor, demonstrating a distant decorin antitumoral effect. Immunochemistry against human decorin and decorin quantitation in tumors confirmed that decorin migrated to the tumor distant site. Furthermore, decorin effect was specific to tumor cells, because neither apoptosis nor growth inhibition were observed in nontumoral human cells such as hepatocytes, endothelial cells, and fibroblasts, despite p21 overexpression.

Adenoviridae↗
PubMed2003

Uptake of plasmid/glycosylated polymer complexes and gene transfer efficiency in differentiated airway epithelial cells.

BACKGROUND: We have studied gene transfer efficiency of glycosylated polylysines and glycosylated polyethylenimines as vectors in immortalized differentiated airway gland serous cells and primary cultures of human airway surface epithelial cells. METHODS AND RESULTS: In both cell types, lactosylated PEI was more efficient for gene transfer than unsubstituted PEI and lactosylated polylysine which requires the presence of endosomolytic agents. However, for all the vectors tested, gene transfer efficiency was lower in differentiated cells as compared with poorly differentiated cells. The presence of membrane lectins, i.e. cell surface sugar-specific receptors, was evaluated using fluorescein-conjugated neoglycoproteins and microscopy or flow cytometry. In differentiated airway surface epithelial cells, membrane lectins were not expressed and plasmid DNA/fluorescein-conjugated glycosylated polymer complexes were not incorporated. This accounted in part for the lack of gene transfer efficiency in these cells. In contrast, in differentiated airway gland serous cells, expression of lectins and their endocytotic properties appeared to be similar to that observed in undifferentiated cells, and plasmid DNA/fluorescein-conjugated glycosylated polymer complexes were incorporated in similar amounts by cells in both differentiated states CONCLUSIONS: Glycosylated PEI appears to be a promising gene delivery system since it is more efficient than the sugar-free polymer and does not require endosomolytic agents. However, in differentiated airway gland serous cells, a low gene transfer efficiency was observed that could not be attributed to low expression of membrane lectins or low uptake of glycosylated complexes. An impaired intracellular trafficking of glycosylated complexes in differentiated airway gland serous cells is suggested.

Cell Line↗
PubMed2003

Metastatic thoracic lymph node carcinoma with unknown primary site.

BACKGROUND: Metastatic cancer in thoracic lymph nodes without a primary site is rare. The purpose of this study is to draw attention to this probably underestimated entity, to speculate on its possible origins, and to suggest guidelines for its treatment. METHODS: Eight heavy smokers with no past medical history of cancer were diagnosed at operation to have malignant cells in intrathoracic lymph nodes (N1 or N2) with no primary site in the lung. All patients underwent an exploratory thoracotomy with a presumed diagnosis of lung cancer except one who presented with a middle lobe mucosa-associated lymphoid tissue lymphoma. We reviewed the type of surgical resection, histologic and immunohistochemical analysis of resected specimens, treatments, survival, and long-term results. RESULTS: Resections performed were pneumonectomy (n = 4), lobectomy (n = 3), and bilobectomy (n = 1). All patients underwent complete mediastinal lymph node dissection. Lung resection was performed for mucosa-associated lymphoid tissue lymphoma (n = 1) and for tumorlike lesions that appeared to be tuberculoma (n = 1) and intrapulmonary metastatic lymph nodes (n = 6). Malignant cells were located in intrapulmonary lymph nodes alone (n = 3) or also in mediastinal lymph nodes in three other cases. All these tumors were cytokeratin-positive, demonstrating their epithelial nature. Pulmonary origin was confirmed in two cases (thyroid transcription factor 1-positive and thyroglobulin-negative). No other origin could be demonstrated by immunochemistry. Three patients died within the first year. All other patients are still alive without recurrence (Kaplan-Meier 5-year survival rate, 62.5%). CONCLUSIONS: Frequency of metastatic cancer in thoracic lymph nodes without a primary site is probably underestimated because the cancer is routinely diagnosed by mediastinoscopy and considered as metastatic disease not amenable to operation. The origin of the disease, either pulmonary, endogenous, or from extrathoracic sites, is often difficult to assess. Nevertheless, our data confirm those of the literature and demonstrate that survival can be increased by operation. This implies diagnosis of the entity and consideration that thoracic lymph node involvement can apparently be isolated and therefore resectable.

Aged↗
PubMed2003

Visceral pleura invasion and pleural lavage tumor cytology by lung cancer: a prospective appraisal.

BACKGROUND: Despite an early-stage diagnosis, lung cancer presenting with visceral pleura invasion (VPI) or malignant pleural lavage cytology (PLC) has a poor prognosis. The purpose of this study was to correlate VPI to malignant PLC. METHODS: One hundred forty-three consecutive patients scheduled for surgical lung resection having undergone preresectional pleural lavage cytology were reviewed. There were 121 malignant and 22 nonmalignant lesions. All cases were studied by pathology, histology, previous transthoracic puncture, VPI, and presence of pleural lymphatic involvement. RESULTS: PLC was positive (n = 13) or suspected (n = 5) for malignant cells in, respectively, 10.7% and 4.1% of patients with lung cancer. There was no positive PLC in cases of nonmalignant disease. PLC was positive only in pT2 tumors and almost always when the tumor was exposed on the pleural surface, thus possibly exfoliating within the pleural space (12/17 patients, 70.6%; p < 0.01). Positive PLC was obtained whatever the histology but did not appear related to previous transthoracic puncture or involvement of pleural lymphatics by tumor cells. CONCLUSIONS: VPI and positive PLC are linked, and the appearance of tumor cells within the pleural cavity can be explained by tumor desquamation. The role that visceral pleura involvement and parietal pleura reabsorption play in lung cancer is of paramount importance and deserves further research. A better understanding of their relationship could have major implications in the therapeutic management of non-small cell lung cancer.

Adenocarcinoma↗
PubMed2003

Complex extralobar sequestration in a 24-year-old woman.

Extralobar sequestration is a congenital acquired disease more frequently observed after birth or during infancy. In half of the cases, it is associated with another malformation. In the following case we report the observation of a 24-year-old female with right extralobar sequestration associated with a diaphragmatic hernia and containing gastric mucosa and a congenital cystic adenomatoid lung malformation. Such malformative lung tissue is known to potentially degenerate and justifies surgery even when patients are asymptomatic.

Adult↗
PubMed2003

Nitric oxide synthase expression by pulmonary arteries: a predictive marker of Fontan procedure outcome?

OBJECTIVES: We retrospectively analyzed lung biopsy specimens from patients who underwent the Fontan procedure to identify predictive markers of outcome. METHODS: We studied the intra-acinar pulmonary arteries present in lung biopsy specimens from 17 patients undergoing the Fontan procedure. We evaluated both their morphology and their expression of endothelial nitric oxide synthase and endothelin 1. We compared these data with those of 6 patients who died of no pulmonary cause (control group). RESULTS: Eight patients had a good surgical outcome (group 1). Their distal arteries were thin and weakly expressed endothelin 1 and endothelial nitric oxide synthase. The procedure failed in 9 patients (group 2). Their distal arteries displayed muscle extension with an increased wall thickness (P <.01 vs group 1). Their endothelin 1 expression remained low (not significant vs group 1). By contrast, endothelial nitric oxide synthase was markedly overexpressed (P <.001 vs group 1). CONCLUSION: Distal pulmonary arteries of patients in whom the Fontan procedure failed exhibited a markedly increased wall thickness and a clear endothelial nitric oxide synthase overexpression. In addition to giving clues to the pathogenesis of the procedure's failure, our study might help to define reliable predictive markers of its outcome.

Adolescent↗
PubMed2002

Long-term reversal of established autoimmunity upon transient blockade of the LFA-1/intercellular adhesion molecule-1 pathway.

Transgenic models and administration of mAbs directed against the LFA-1/intercellular adhesion molecule 1 (ICAM-1) pathway have shown that these costimulatory molecules play a key role in generating effector cells mediating inflammatory responses. In this report, durable remission of recent diabetes in nonobese diabetic (NOD) mice was induced by transient expression of an immunoadhesin gene encoding the soluble form of ICAM-1 (sICAM-1/Ig). A single i.v. injection of an adenovirus vector encoding the immunoadhesin gene led to 70% diabetes remission as opposed to 0% in mice injected with a control adenovirus vector. Despite the rapid decline of sICAM-1/Ig serum levels, diabetes remission remained stable in 50% of NOD mice for >6 mo. sICAM-1/Ig expression also led to long-term protection against diabetes in prediabetic NOD mice. sICAM-1/Ig in vitro induced an agonistic effect of T cell activation in a TCR-transgenic model, increasing T cell proliferation and IL-2 secretion. Importantly, protected mice were not immunosuppressed because they rejected skin allografts normally and developed immunity against the adenovirus vector. Rather, sICAM-1/Ig induced active tolerance, as assessed by the persistence of diabetogenic T cells in protected mice and the reversal of protection by immunosuppression with cyclophosphamide.

Adenoviridae↗
PubMed2002

Characteristics and prognosis of resected T3 non-small cell lung cancer.

BACKGROUND: T3 tumors can be divided into several subgroups depending on the type of anatomical structure invaded: chest wall, mediastinal pleura, or main bronchus. The aim of this study was to analyze the characteristics and prognosis of each subgroup of T3 tumors. METHODS: The results of surgical treatment were retrospectively analyzed for 261 patients with T3 non-small cell lung cancer invading either the mediastinal pleura or parietal pericardium by direct extension (mediastinal pT3, n = 68), or main bronchus (bronchial pT3, n = 68), or chest wall (chest wall pT3, n = 125) that were operated on between 1984 and 1996. Complete resection including radical mediastinal lymph node dissection was intended in all patients. One patient had segmentectomy, 91 had lobectomy (34.9%), and 169 had pneumonectomy (64.8%). One hundred and fifty-eight patients received adjuvant radiation therapy and 7 patients received both adjuvant chemotherapy and radiation therapy. Actuarial survival curves were drawn using the Kaplan-Meier method and risk factors for late death were identified. RESULTS: In-hospital mortality was 6.1%. Follow-up was 98% complete. Global 5-year survival was 28%, with survival being not significantly different among the three subgroups: 34.9%, 30.6%, and 22.5% (p = 0.19) in the bronchial pT3, mediastinal pT3, and chest wall pT3 subgroups, respectively. Resection margins were microscopically invaded in 33 patients (12.6%). Seventy-four patients had N1 involvement (28.4%) and 78 patients had N2 involvement (29.8%). N0 involvement was more prevalent in the chest wall pT3 subgroup, whereas N1 involvement was more prevalent in the bronchial pT3 subgroup and N2 involvement was more prevalent among patients with mediastinal invasion. Pathologic factors influencing the 5-year survival were tumor size (p = 0.03) and N involvement (p = 0.003). Histology, type of surgical resection (lobectomy versus pneumonectomy), and use of adjuvant therapy did not influence survival significantly. CONCLUSIONS: Five-year survival was not significantly different among the three subgroups of pT3 non-small cell lung cancer, although bronchial pT3 tumors tended to have a better prognosis and chest wall pT3 tumors tended to have a worse prognosis. The pathologic characteristics of each pT3 subgroup seems different. Further research is warranted to explore the pathologic and biological factors influencing prognosis for each pT3 subgroup.

Adenocarcinoma↗
PubMed2002

Histomorphometric analysis of pulmonary vessels in single ventricle for better selection of patients for the Fontan operation.

OBJECTIVE: In cases of single-ventricle physiology, the Fontan procedure often fails even when the usual selection criteria are strictly respected. We analyzed specimens from intraoperative open lung biopsies performed on 40 patients with single-ventricle physiology who were considered to be good candidates for the Fontan procedure. Histomorphometric study was performed to determine histologic factors predictive of failure of the Fontan procedure. METHODS: Histomorphometric studies were performed on samples from 40 patients aged 6 months to 23 years with single-ventricle physiology, either tricuspid atresia (n = 14) or univentricular heart (n = 26). The preoperative pulmonary arterial pressure was 18 mm Hg or less in 35 cases and greater than 18 mm Hg in 5 cases. Eighteen patients underwent total cavopulmonary connection, 16 patients underwent partial cavopulmonary connection, and 6 underwent a palliative procedure, as determined according to clinical and hemodynamic findings. RESULTS: Lung biopsy specimens from all 5 patients with pulmonary arterial pressure greater than 18 mm Hg appeared abnormal, whereas they appeared abnormal only 51% of the time in the low pulmonary arterial pressure group. The most frequent histologic abnormality observed was extension of smooth muscle cells in the wall of distal intra-acinar pulmonary arteries. Of the 18 patients who underwent the Fontan procedure, 9 had normal distal pulmonary arteries and good surgical results (except 1 with the Fontan circulation taken down for an anatomic reason). The remaining 9 had thick-walled distal intra-acinar pulmonary arteries with poor results of the Fontan procedure, and 6 died. The mean percentage wall thickness of small intra-acinar pulmonary arteries was significantly greater among the patients with bad results than among those with good results of the procedure (P <.01). CONCLUSIONS: Lung biopsy specimens were abnormal in 51% of patients with low pulmonary arterial pressure, there was no relationship between preoperative pulmonary arterial pressure and outcome, and extension of muscle in peripheral arteries was always present in cases of failure of the Fontan procedure. Histomorphometric study is therefore a useful adjunct to the usual selection criteria for surgical decision making in cases of single-ventricle physiology.

Adolescent↗
PubMed2002

Pyothorax-associated lymphoma: a peculiar clinicopathologic entity derived from B cells at late stage of differentiation and with occasional aberrant dual B- and T-cell phenotype.

We report 12 European cases of pyothorax-associated lymphomas occurring 30-67 years following artificial pneumothorax for pleuropulmonar tuberculosis. Eleven patients presented with a localized pleural tumor mass, whereas one patient also had liver involvement. Histologic examination showed a diffuse proliferation of large lymphoid cells with frequent plasmacytoid differentiation (n = 8), expressing CD20 (n = 10), CD79a (n = 11), and/or CD138 (n = 5) B-cell antigens. Aberrant expression of T-cell markers (CD2, CD3, CD4) was noted in five cases. The B-cell origin of lymphoma cells was confirmed by the demonstration of immunoglobulin light chain restriction or clonal B cell population in six cases. In 11 of 12 cases in situ hybridization disclosed Epstein-Barr virus genome in most tumor cells and immunohistochemistry a type III LMP-1+/ EBNA-2+ latency profile. HHV-8/ORF73 antigen was not detected in all tested cases (n = 11). All investigated cases (10 of 10) disclosed a uniform CD10-/BCL-6-/MUM1+/CD138+/- phenotype, consistent with a derivation from late germinal center (GC)/post-GC B cells. Clinical outcome was poor with a median survival time of 5 months. Only one patient was in complete remission after 34 months. This study further confirms that pyothorax-associated lymphoma represents a distinct clinicopathologic entity among diffuse large B-cell lymphoma, which is characterized by a peculiar clinical presentation, frequent plasmacytoid features, and a strong association with EBV. Moreover, we show that this lymphoma entity likely originates from B cells at a late stage of differentiation and occasionally shares an aberrant dual B/T phenotype.

Aged↗
PubMed2002

Fluticasone propionate inhibits lipopolysaccharide-induced proinflammatory response in human cystic fibrosis airway grafts.

Airway inflammation, one of the major factors leading to lung damage in cystic fibrosis (CF) patients, is associated with an abnormal increase in proinflammatory cytokines. In this work, we demonstrate the increased release of the proinflammatory cytokines after lipopolysaccharide (LPS) stimulation: human interleukin (hIL)-8 in CF and non-CF airway xenografts, and hIL-6 and human growth-related oncogene-alpha (hGRO-alpha), which could be only analyzed in non-CF xenografts. Under basal conditions, we observed that hIL-8 was higher in CF xenografts compared with non-CF. We also report the anti-inflammatory effect of a glucocorticoid, fluticasone propionate (FP), on CF airway epithelium using a humanized model of airway inflammation developed in nude mice. In CF and non-CF tracheal xenografts, airway inflammation was induced by inoculating Pseudomonas aeruginosa LPS (4 h; 1 microg/ml) in the lumen of the xenografts. FP pretreatment (2 h; 10(-8) M) followed by P. aeruginosa LPS stimulation induced a significant reduction of LPS-induced hIL-8 release in airway liquid collected from CF and non-CF tracheal xenografts (85 and 80%, respectively). In non-CF tracheal xenografts, FP treatment before LPS stimulation induced a significant decrease in hIL-6 and hGRO-alpha. From these data, we suggest that FP exerts anti-inflammatory properties that may be appropriate to CF therapy, at an early stage of the disease. In addition, these results demonstrate that the humanized airway model of inflammation provides a relevant tool for analyzing the effects of anti-inflammatory drugs in different diseases in which airway inflammation is implicated.

Androstadienes↗