Search PubMed⌕ Search

Biomedical subjects

J M Vignaud

Publications and source records attributed to J M Vignaud.

At least 37 records · Page 2Linked to original sources

Cytokines in human lung fibrosis.

Fibrosis is a pathological process characterized by the replacement of normal tissue by mesenchymal cells and the extracellular matrix produced by these cells. The sequence of events leading to fibrosis of an organ involves the subsequent processes of injury with inflammation and disruption of the normal tissue architecture, followed by tissue repair with accumulation of mesenchymal cells in the area of derangement. The same sequence of events occurs in wound healing with normal granulation tissue and scar formation, but, while normal scar formation is very localized and transient, in contrast, in fibrosis, the repair process is exaggerated and usually widespread and can be chronic. Inflammatory cells (mainly mononuclear phagocytes), platelets, endothelial cells, and type II pneumocytes play a direct and indirect role in tissue injury and repair. The evaluation of three human fibrotic lung diseases, two diffuse [idiopathic pulmonary fibrosis (IPF), and the adult respiratory distress syndrome (ARDS)], and one focal (tumor stroma in lung cancer), has shown that several cytokines participate to the local injury and inflammatory reaction [interleukin-1 (IL-1), interleukin-8 (IL-8), monocyte chemotactic protein-1 (MCP-1), tumor necrosis factor-alpha (TNF-alpha)], while other cytokines are involved in tissue repair and fibrosis [platelet-derived growth factor (PDGF), insulin-like growth factor-1 (IGF-1), transforming growth factor-beta (TGF-beta), and basic-fibroblast growth factor (b-FGF)]. A better understanding of the cytokines and cytokine networks involved in lung fibrosis leads to the possibility of new therapeutic approaches.

Cytokines↗

The role of cytokines in human lung fibrosis.

Fibrosis is a disorder characterized by a qualitative and quantitative alteration of the deposition of extracellular matrix with accumulation of mesenchymal cells in replacement of normal tissue. The sequence of events leading to fibrosis of an organ involves the subsequent processes of injury with inflammation and disruption of the normal tissue architecture, followed by tissue repair with accumulation of mesenchymal cells in this area. A similar sequence of events occurs in wound healing with formation of normal, limited and transient granulation tissue, while in fibrosis, a maladaptive repair leads to an extensive, exaggerated process with functional impairment. Inflammatory cells (mainly mononuclear phagocytes), platelets, endothelial cells, and type II pneumocytes play a direct and indirect role in tissue injury and repair. The evaluation of several human fibrotic lung diseases, five diffuse (idiopathic pulmonary fibrosis (IPF); adult respiratory distress syndrome (ARDS); coal workers' pneumoconiosis (CWP); Hermansky-Pudlak syndrome (HPS); systemic sclerosis (SS)) and two focal (tumour stroma in lung cancer; and obliterative bronchiolitis (OB) after lung transplantation), has shown that several cytokines participate in the local injury and inflammatory reaction (interleukin-1 (IL-1), interleukin-8 (IL-8), monocyte chemotactic protein-1 (MCP-1), and tumour necrosis factor-alpha (TNF-alpha)), while other cytokines are involved in tissue repair and fibrosis (platelet-derived growth factor (PDGF), insulin-like growth factor-1 (IGF-1), transforming growth factor-beta (TGF-beta), and basic-fibroblast growth factor (b-FGF)). A better understanding of the cytokines and cytokine networks involved in lung fibrosis leads to the possibility of new therapeutic approaches.

Cytokines↗

[False empyema after artificial pneumothorax. An original entity: type B non Hodgkin malignant lymphoma].

Malignant lymphoma developing in the lung after therapeutic pneumothorax is a rare condition in Europe. The authors report one case admitted after a 40-year history of pyothorax resulting from artificial pneumothorax for treatment of pulmonary tuberculosis. The diagnosis at admission was an infection of the chronic pyothorax associated with a lung mass. Histology confirmed the presence of non-hodgkin lymphoma B in the lung mass associated with Epstein-Barr virus. After surgery, chimiotherapy was not effective. Diagnosis before surgery could optimize the medical management. The long-term outcome is pejorative in most cases.

Aged↗

Cell and tissue distribution of synthetic oligonucleotides in healthy and tumor-bearing nude mice. An autoradiographic, immunohistological, and direct fluorescence microscopy study.

Antisense oligonucleotides have the ability to inhibit individual gene expression in the potential treatment of cancer and viral diseases. However, the way parenterally administered oligonucleotides distribute themselves into healthy tissues or tumors is poorly understood. In this study, the cell and tissue distribution of two modified or unmodified phosphodiester pentadeca-beta-oligonucleotides intravenously administered to healthy or tumor-bearing nude mice was assessed by autoradiography as well as by direct fluorescence and immunoenzymatic histological methods. Resistance of oligonucleotides to degradation by nuclease activity was previously studied in vitro. Using these methods we were able to show the following: 1) within minutes, oligonucleotides permeate all cells and tissues with the exceptions of erythrocytes and intervertebral discs; 2) cell and tissue distribution does not depend on the sequence of the given oligonucleotide; 3) concentration of oligonucleotides is higher within the connective tissue cells than in the interstitial matrix; 4) after uptake, oligomers partition throughout all of the cellular compartments, including at the highest intracellular concentrations in the nuclei; 5) oligonucleotides penetrate easily the tumor cell compartments, oligonucleotide diffusion being unimpeded by the extracellular matrix.

Animals↗

The role of platelet-derived growth factor production by tumor-associated macrophages in tumor stroma formation in lung cancer.

Lung cancer is the most common cause of death by cancer in developed countries. Since a tumor cannot develop without the parallel expansion of a tumor stroma, a better understanding of its formation could lead to new therapeutical approaches. In this respect, since platelet-derived growth-factor (PDGF) is a chemotactic and growth factor for mesenchymal and endothelial cells, lung tumors of patients undergoing surgery for non-small cell lung cancer were evaluated for their replication rate using iododeoxyuridine incorporation, and for the expression of PDGF genes and the presence of PDGF A and B chains and of PDGF receptor alpha and beta subunits. This observation demonstrates that: (a) tumor cells and stroma mesenchymal cells, but not tumor-associated macrophages, display a high replication rate; (b) 1 of 3 tumors are characterized by cancer cells expressing the genes for PDGF A and/or B chains, while 1 of 2 tumors are composed of tumor cells presenting PDGF receptors alpha and beta subunits on their surface, and in only 1 of 6 tumors, tumor cells coexpress PDGF and its receptor; (c) in almost all tumors, tumor-associated macrophages express PDGF A and/or B chain genes; (d) mesenchymal cells, as well as endothelial cells, do not express PDGF A and B chain genes but do express PDGF receptor alpha and beta subunits; and (e) an ongoing active process was suggested in the periphery of the tumor by the simultaneous strong expression of PDGF A and B chain genes by tumor-associated macrophages and the high replication rate of mesenchymal and endothelial cells in the same area. Thus, PDGF is likely to have a limited autocrine role in tumor cell replication but is a potential player, in a paracrine fashion, in tumor stroma development.

Carcinoma, Non-Small-Cell Lung↗

Blood monocyte chemotaxis.

Migration is a prerequisite for blood monocytes to exert their biological activities, since they have to migrate from blood into the tissues where they transform into macrophages. In vivo chemotaxis of blood monocytes is seldom evaluated, while their in vitro ability to migrate is frequently tested. The most frequently used test relies on BM migration through filters using modified Boyden chemotactic chambers. Using checkerboard analysis it is possible to define chemotactic and chemokinetic factors.

Biological Assay↗

Simian virus 40 large tumor antigen-immortalized normal human liver epithelial cells express hepatocyte characteristics and metabolize chemical carcinogens.

Normal human liver tissue and cultured human hepatocytes are valuable models to study xenobiotic metabolism and toxicity, but they only have a limited in vitro life-span and are not readily available. This report describes the establishment of replicative cultures of human adult liver epithelial cells in serum-free medium. The longevity of three of these cultures, derived from different donors, was extended by introduction of the simian virus 40 large T antigen gene. Two cell lines, THLE-2 and -3, established with a recombinant simian virus 40 large T antigen virus have undergone > 100 population doublings, are nontumorigenic when injected into athymic nude mice, have near-diploid karyotypes, and do not express alpha-fetoprotein. The cells express cytokeratin 18 and albumin in early passage, whereas higher-passage cells in logarithmic-phase growth also express cytokeratin 19. THLE-2 and -3 cells metabolize benzo[a]pyrene, N-nitrosodimethylamine, and aflatoxin B1 to their ultimate carcinogenic metabolites that adduct DNA, which indicates functional cytochrome P450 pathways. Other enzymes involved in metabolism of chemical carcinogens, such as epoxide hydrolase, NADPH cytochrome P450 reductase, superoxide dismutase, catalase, glutathione S-transferases, and glutathione peroxidase are also retained by THLE cells. Thus, these immortalized human liver cells constitute an in vitro model for pharmacotoxicological studies and for the investigation of etiology and pathogenesis of human hepatocellular carcinoma.

Adult↗

[Müllerian adenosarcoma. Apropos of a case].

Müllerian adenosarcoma is an uncommon disease of the female genital tract with a special place among mixed müllerian tumors because of its slow and more favorable clinical course. This tumor is composed of a benign epithelial contingent and a sarcomatous one. A case of Müllerian adenosarcoma clinically characterized by an atypical outset is described and the literature is reviewed.

Endometriosis↗

[Olfactory esthesioneuroma (esthesioneuroblastoma). A pathologic study of 7 cases].

With an histological, immunohistochemical study of 7 cases of olfactory esthesioneuromas (4 of them had an ultrastructural study), our purpose was to revise the problem of the too often ambiguous terminology and of the different histological lower classes classifications of these tumors. Our own results and the literature demonstrate that they are polymorphic. In standard histology, they are often right diagnosed but an immunohistochemical study can be useful and an ultrastructural study absolutely necessary for a reliable diagnosis. For an easier nomenclature, we advise to use only one terminology for these tumors = olfactory esthesioneuroma. But, because of their important polymorphism, we keep to an histological lower classes classification according to their degree of differentiation in light microscopy: well differentiated tumors (old esthesioneuroepitheliomas), moderately differentiated tumors (old esthesioneurocytomas), poorly differentiated tumors (old esthesioneuroblastomas and so on described as neuro-endocrine carcinomas by Silva and al).

Adolescent↗

Squamous metaplasia expression of proto-oncogenes and P 53 in lung cancer patients.

BACKGROUND: The question of whether bronchial squamous metaplasia is a true preneoplasia is important and demonstrated in animal for several carcinogens. We have now approached this problem in humans and in vivo. EXPERIMENTAL DESIGN: Squamous metaplasia in the close vicinity of surgically resected lung tumors were evaluated for their mitotic index and screened for proto-oncogenes and P 53 protein expression by immunohistochemistry and/or in situ hybridization. RESULTS: Among 16 patients, 4 had squamous metaplasia positive for either myc messages and/or for P 53 protein accumulation. In the same patients (3/4), the autologous bronchial tumors were also positive for the same markers. Squamous metaplasia positivity was observed essentially in patients with advanced diseases and only in squamous cell carcinomas. In addition, when evaluated with 5 iodo-2'-deoxyuridine systemic infusion, all patients presented hyperproliferative basal squamous metaplasic cells. CONCLUSIONS: These results are reminiscent of the typical preneoplastic changes observed in familial colic adenomatosis, where genetic changes accumulate in hyperproliferative cells. They also suggest that bronchial squamous metaplasia could be an authentic preneoplasia in, at least, squamous cell carcinomas.

Gene Expression Regulation, Neoplastic↗

Mechanism for the recruitment of macrophages to cancer site. In vivo concentration gradient of monocyte chemotactic activity.

BACKGROUND: Tumor stroma is characterized by the development of new blood vessels, an inflammatory cell infiltration, and a fibrotic reaction. The inflammatory component of tumor stroma plays an important role in the modulation of tumor expansion. In this respect, macrophages constitute a major part of the inflammatory cell infiltration and can exert cytotoxic activity against tumor cells. The accumulation of macrophages in the vicinity of the tumor suggests their recruitment from circulating blood monocytes through the local release of chemotactic factors for monocytes. METHODS: To detect the existence of a concentration gradient of monocyte chemotactic activity (MCA) between the tumor vicinity and blood vessels, malignant pleural effusions defined by the local presence of cancer cells were evaluated for quantification of MCA. RESULTS: Unlike nonmalignant pleural effusions, malignant pleural effusions were characterized by the presence of increased levels of MCA, and in lung adenocarcinoma (a cancer with high inflammatory cell infiltration), pleural levels of MCA were significantly greater than in small cell lung carcinoma (a cancer with low inflammatory cell reaction). An MCA concentration gradient between pleural fluid and plasma was present in malignant effusions because pleural MCA levels in all cancer types were significantly greater than MCA levels in the plasma of the same patients. CONCLUSIONS: Thus, an increased local level of MCA is a feature of cancers with high inflammatory cell infiltration, and the presence of an in vivo concentration gradient of MCA suggests the direct role of this biologic activity in recruiting blood monocytes to the cancer site.

Adenocarcinoma↗

Host-donor interactions in healing of human split-thickness skin grafts onto nude mice: in situ hybridization, immunohistochemical, and histochemical studies.

The behavior of host and donor cell lines in human split-thickness skin grafts onto nude mice was studied by in situ hybridization (ISH) using genomic DNAs as probes, and immunohistochemically with species-specific or cross-species specific antibodies, at different stages ranging from day 3 to more than 1 year following grafting. Changes in the graft vascular and interstitial extracellular matrix were also assessed using species-specific or cross-species specific antibodies to human or murine type I, III, and IV collagens. Finally, transplant reinnervation was investigated using antibodies to various nerve cytoplasmic antigens and the thiocholine method to demonstrate acetylcholinesterase. Using these methods we were able to show the following: (1) the graft epidermis that is not replaced by mouse keratinocytes is progressively colonized by recipient Langerhans cells (LCs); (2) revascularization of the grafts begins soon by inoculation of the graft vessels with the host microcirculatory bed, and mouse endothelial cells growing into preexisting human capillary tubes produce a new basement membrane, prior to the replacement of the original one; (3) within 3-5 days following grafting, mouse fibroblasts migrate into the graft dermis. The density of the human and murine fibroblast populations then progressively increases. Characterization of the interstitial collagens identifies both human and murine type I and III collagens. Production of type III collagens decreases during the progression of fibrogenesis while human type I collagen becomes the predominant matrix protein; (4) transplant reinnervation is deficient, and neurites growing into severed graft nerve trunks were never detected.

Animals↗

Characterization of a tumor necrosis factor-alpha inhibitor activity in cancer patients.

To evaluate the feasibility of tumor necrosis factor-alpha (TNF-alpha) treatment of lung cancer patients, we chose the malignant cells contained in their pleural effusions as a first convenient target. We found, however, that a TNF-alpha inhibitor (TNF-alpha I) activity was present in both patient sera and pleural fluids. We therefore compared the TNF-alpha I activity present in patients with benign or malignant pleural effusions using a bioassay of TNF-alpha inhibition and partially characterized it. A high TNF-alpha I activity characterizes cancer patients with sera levels twice as high as the control level measured for blood bank donors (2.54 +/- 1.28 versus 1.19 +/- 0.38) and with even higher levels in pleural fluids (3.75 +/- 1.83). In contrast, patients with benign pleural effusions present similar levels of TNF-alpha I activity, at about the control level, in both their sera and pleural fluids (1.37 +/- 0.98 versus 1.16 +/- 0.85). A high TNF-alpha I activity is consistently found in cancer patients but is only released in vitro by leukocytes. It is most likely related to recently purified TNF-alpha inhibitors that, as soluble shed fragments of TNF receptors, may function as traps for TNF molecules. This study suggests that tumors may evade TNF cytotoxic action by modulating systemic levels of TNF and implies a reassessment of TNF therapy in cancer patients.

Adult↗