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E Ferrero

Publications and source records attributed to E Ferrero.

At least 37 records · Page 2Linked to original sources
PubMed1998

Tumor-driven matrix invasion by infiltrating lymphocytes: involvement of the alpha1 integrin I-domain.

Here we show that tumor cells (TC) from renal cancers regulate the migratory properties of autologous tumor-infiltrating lymphocytes (TIL), enhancing their ability to invade the extracellular matrix. A similar effect is exerted by human recombinant macrophage chemotactic protein 1 (MCP-1) and IL-8, chemokines known to increase T lymphocyte migration both across vascular endothelium and subendothelial matrix. We found that TC freshly derived from renal cell carcinoma surgical specimens constitutively secrete both IL-8 and MCP-1 and that TIL express both specific receptors. TIL matrix invasion elicited by TC is inhibited by the addition of neutralizing antisera specific for IL-8 and MCP-1, demonstrating the direct relationship between chemokine release by TC and TIL invasion. Of note, TIL invasion of the extracellular matrix requires the alpha1 integrin, which acts through its I-domain that is upregulated upon culture with MCP-1 and IL-8. Collectively, these findings suggest that TC may actively recruit TIL via the release of chemotactic factors that enhance an alpha1 integrin-mediated pathway of matrix invasion.

Antigens, CD↗
PubMed1997

Human CD38, a leukocyte receptor and ectoenzyme, is a member of a novel eukaryotic gene family of nicotinamide adenine dinucleotide+-converting enzymes: extensive structural homology with the genes for murine bone marrow stromal cell antigen 1 and aplysian ADP-ribosyl cyclase.

The human leukocyte Ag CD38 is a 45-kDa type II membrane glycoprotein that functions both as a transmembrane signaling receptor and as an ectoenzyme. CD38 can transmit positive or negative signals regulating T and B lymphocyte proliferation and differentiation and can enzymatically convert nicotinamide adenine dinucleotide to cyclic ADP-ribose, a potent intracellular calcium releaser. To begin the genetic analysis of CD38, we have isolated and characterized the human CD38 gene, previously mapped to chromosome 4. Human CD38 is encoded by a single copy gene that extends over > 62 kb and consists of eight exons and seven introns, including a very long intron that interrupts the 5' coding region. The 5' upstream region of the gene is characterized by the absence of canonical TATA and CAAT boxes, the presence of a GC-rich tract immediately upstream of the initiator codon, several transcription start sites, and potential binding sites for the immunologic transcription factors T cell-specific transcription factor alpha, nuclear factor-IL-6, and interferon responsive factor-1. Comparison of the genomic structure of human CD38 with that of the genes for murine bone marrow stromal Ag bone marrow stromal cell antigen 1/BP-3 and aplysian ADP-ribosyl cyclase, which encode proteins related to CD38 in sequence and function, reveals their striking structural similarity. This strongly suggests that the three genes evolved from a common ancestor from which CD38 and bone marrow stromal cell antigen 1 arose by gene duplication before the divergence of humans and rodents.

ADP-ribosyl Cyclase↗
PubMed1996

Integrin-dependent induction of functional urokinase receptors in primary T lymphocytes.

In order to reach the sites of inflammation, lymphocytes leave the bloodstream and migrate into peripheral tissues, in a process involving integrin-mediated adhesion to the vascular endothelium, followed by transmigration across the endothelial barrier and through the underlying interstitial matrix. We have investigated the role of the plasminogen activator/plasmin system in normal T cell migration. Receptors for urokinase plasminogen activator (uPAR) were not expressed in resting T lymphocytes, but could be efficiently induced at the mRNA and protein level by coclustering of the antigen receptor complex and beta1 or beta2 integrins, through a signalling pathway involving both protein kinase C activation and an increase in intracellular cyclic AMP. Catalytic activation of plasminogen by uPAR-expressing T cells promoted their migration through an extracellular matrix in vitro. Plasmin-induced invasion was inhibited by plasmin-and urokinase inhibitors and by anti-uPAR antibodies. Finally, cytofluorimetric and immunohistochemical analysis of primary human tumor specimens showed the presence of uPAR positive infiltrating T cells in vivo. Collectively, these findings suggest that plasminogen activation may play a role in lymphocyte migration in vivo, and that integrin-dependent expression of membrane-associated endopeptidases could represent an additional step in the regulated process of leukocyte transmigration.

Adenylyl Cyclases↗
PubMed1996

Tumor necrosis factor alpha-induced vascular leakage involves PECAM1 phosphorylation.

Herein we show that exposure of human umbilical vein endothelial cells to tumor necrosis factor alpha (TNFalpha) led to platelet endothelial cell adhesion molecule-1 (PECAM1) surface redistribution, disruption of cytoskeleton connections, and increased PECAM1 phosphorylation, accompanied by increased permeability to macromolecules. The in vitro use of inhibitors of tyrosine or serine-threonine kinases could prevent both PECAM1 surface redistribution and the increase in permeability induced by the cytokine. In vivo administration of lavendustin A, a natural tyrosine kinase inhibitor, protected endothelial cells from TNFalpha-dependent vascular leakage in mouse liver. We propose that the involvement of PECAM1 in TNFalpha-mediated effects on vascular permeability may depend on a dynamically regulated cytoskeletal association, related to the degree of PECAM1 phosphorylation.

Alkaloids↗
PubMed1996

CD31/PECAM-1-driven chemokine-independent transmigration of human T lymphocytes.

We assessed the relative contribution of CD31/PECAM-1 (platelet-endothelial cell adhesion molecule-1) to T lymphocyte transmigration by the use of transfected murine fibroblasts stably expressing either the human CD31/PECAM-1 or the intercellular adhesion molecule-1 (CD54/ICAM-1). Unlike CD54/ICAM-1, CD31/PECAM-1 supported migration of activated T cells in the absence of chemokines: most of the migrating lymphocytes were CD31+ and displayed a phenotype corresponding to the naive subpopulation (LFA-1 dull and CD45RA+). Migration of activated T lymphocytes through CD54/ICAM-1+ transfected monolayers could be induced by creating a chemotactic gradient with the chemokine monocyte chemotactic protein-1, and the migrating cells mainly displayed a memory phenotype (LFA-1 bright CD45RO+) under these conditions. Furthermore, we found that in transfected cells CD54/ICAM-1 is uniformly distributed along the apical surface of the cells, while CD31/PECAM-1 is concentrated at the intercellular junctions, suggesting the existence of a haptotactic gradient (i.e. a gradient of substrate- or cell-bound molecules) responsible for T cell migration. This was also confirmed by the finding that monolayers of murine fibroblasts transfected with a CD31/PECAM-1 mutant lacking the cytoplasmic domain (CD31/PECAM-1-delta cyto), which has a reduced tendency to localize at cell-cell contact areas, supported efficient adhesion but were unable to induce migration of activated T cells unless a chemotactic gradient was created. We propose that in lymphocytes, homophilic CD31/PECAM-1 adhesion may be primarily involved in transmigration of naive T cells and that its role is complementary to that of CD54/ICAM-1.

3T3 Cells↗
PubMed1996

The anti-ischemic drugs defibrotide and oligotide analogously inhibit leukocyte-endothelial cell adhesion in vitro.

Defibrotide (a polydeoxyribonucleotide) and oligotide (an oligodeoxyribonucleotide) obtained from mammalian single-stranded DNA, have been demonstrated to have anti-ischemic activity in some experimental models of ischemia/reperfusion of kidney in rats. We hypothesized that their anti-ischemic activity could be related to an inhibition of leukocyte-endothelial cell adhesion and also the consequent generation of oxygen free radicals by leukocytes. We studied the in vitro adhesion of neutrophils to human umbilical vein endothelial cells under basal conditions and following neutrophil or endothelial cell activation (using 10(-7) fMLP and 500 U/ml TNF-alpha, respectively). Defibrotide and oligotide significantly inhibited neutrophil adhesion to endothelial cells (after only 1 min of drug treatment). When the anti-LFA-1 70H12 F(ab)2 monoclonal antibody was used, the drugs exerted only slight additional inhibition of the adhesion of fMLP-activated neutrophils to endothelium. These results, confirmed in NIH/3T3-ICAM-1-transfected cells, demonstrate that defibrotide and oligotide interfere with leukocyte adhesion to endothelial cells by an LFA-1-dependent mechanism.

3T3 Cells↗
PubMed1996

Resistance to endotoxin shock and reduced dissemination of gram-negative bacteria in CD14-deficient mice.

Endotoxin shock is the result of activation of the immune system by endotoxin/LPS, a component of Gram-negative bacteria. CD14, a GPI-anchored glycoprotein expressed strongly by monocyte/macrophages, is one of several receptors for endotoxin/LPS. The role of CD14 in bacterial-induced and LPS-induced shock was tested in CD14-deficient mice produced by gene targeting in embryonic stem cells. CD14-deficient mice were found to be highly resistant to shock induced by either live Gram-negative bacteria or LPS; however, at very high concentrations of LPS or bacteria, responses through non-CD14 receptors could be detected. Surprisingly, CD14-deficient mice also showed dramatically reduced levels of bacteremia, suggesting an unexpected role for CD14 in the dissemination of Gram-negative bacteria.

Animals↗
PubMed1996

Drug-induced in vitro inhibition of neutrophil-endothelial cell adhesion.

1. Leukocyte-endothelial cell interactions play an important role during ischaemia-reperfusion events. Adhesion molecules are specifically implicated in this interaction process. 2. Since defibrotide has been shown to be an efficient drug in reducing damage due to ischaemia-reperfusion in many experimental models, we analysed the effect of defibrotide in vitro on leukocyte adhesion to endothelial cells in basal conditions and after their stimulation. 3. In basal conditions, defibrotide (1000 micrograms ml-1) partially inhibited leukocyte adhesion to endothelial cells by 17.3% +/- 3.6 (P < 0.05), and after endothelial cell stimulation (TNF-alpha, 500 u ml-1) or after leukocyte stimulation (fMLP, 10(-7) M), it inhibited leukocyte adhesion by 26.5% +/- 3.4 and 32.4% +/- 1.8, respectively (P < 0.05). 4. In adhesion blockage experiments, the use of the monoclonal antibody anti-CD31 (5 micrograms ml-1) did not demonstrate a significant inhibitory effect whereas use of the monoclonal antibody anti-LFA-1 (5 micrograms ml-1) significantly interfered with the effect of defibrotide. 5. This result was confirmed in NIH/3T3-ICAM-1 transfected cells. 6. We conclude that defibrotide is able to interfere with leukocyte adhesion to endothelial cells mainly in activated conditions and that the ICAM-1/LFA-1 adhesion system is involved in the defibrotide mechanism of action.

Cell Adhesion↗
PubMed1995

The platelet endothelial cell adhesion molecule-1 (PECAM1) contributes to endothelial barrier function.

In this study we have analyzed the role of the platelet-endothelial cell adhesion molecule-1 (PECAM1) in vascular barrier function. PECAM1 is an immunoglobulin gene superfamily member expressed by endothelial cells at the cell boundaries. Macromolecule permeability assays performed on cell monolayers that express native or transfected PECAM1, indicated that the molecule participates in the establishment and maintenance of vascular barrier function in vitro. This hypothesis was confirmed by the finding that in vivo injection of the specific monoclonal antibody directed against the murine vascular PECAM1 led to a detectable leakage of hepatic and renal blood vessels.

Animals↗
PubMed1995

Experimental Listeria meningoencephalitis. Macrophage inflammatory protein-1 alpha and -2 are produced intrathecally and mediate chemotactic activity in cerebrospinal fluid of infected mice.

In bacterial meningitis, the recruitment of leukocytes across the blood-brain barrier into the central nervous system may be crucial for both elimination of pathogens and tissue injury. In addition to bacterial cell wall products, host factors including chemokines may lead to accumulation of phagocytes within the central nervous system. As shown by Northern analysis, brains of mice infected intracerebrally with Listeria monocytogenes (LM) express mRNA for three chemokines, the macrophage inflammatory protein (MIP)-1 alpha, MIP-1 beta, and MIP-2. The cellular sources of these chemokines comprise both the blood-derived polymorphonuclear leukocytes (PMNs) and monocytes infiltrating the meninges, the ventricular system and the periventricular area. In the course of meningitis a time-dependent increase of MIP-1 alpha and MIP-2 was found in the cerebrospinal fluid (CSF) by ELISA. CSF taken 24 h after infection (CSF-LM24) induced migration of human leukocytes when treated in chemotactic chambers in vitro. Neutralizing Abs to chemokines identified MIP-1 alpha and MIP-2 to be responsible for CSF-LM24 mediated chemotaxis of monocytes and PMNs, respectively. CSF obtained from mock-infected animals contained no MIP-1 alpha or MIP-2 and did not lead to migration of leukocytes. When testing CSF-LM24 on mouse spleen cells, the chemotactic activity detected for mononuclear cells was only partly inhibited by Abs to MIP-1 alpha and -1 beta. Thus, in addition to MIP-1 and -2 other not yet defined chemotactic factors are of importance for recruitment of leukocytes in bacterial meningitis.

Animals↗
PubMed1995

IDDM in the province of Pavia, Italy, from a population-based registry.A descriptive study.

OBJECTIVE: To report the incidence of insulin-dependent diabetes mellitus (IDDM) in the Province of Pavia, Italy, in the 0- to 29-year-old age-group between 1988 and 1992. Urban versus rural residence, socioeconomic level, and family size of IDDM cases were also investigated. RESEARCH DESIGN AND METHODS: A prospective register was established in 1988 to collect all newly diagnosed IDDM patients with onset before 30 years of age. The primary data source was based on notification of new cases by hospitals, out-patient clinics, family doctors, and pediatricians. The secondary and independent data source consisted of the registries of prescriptions for insulin syringes in the health districts of the province. RESULTS: In 5 years (1988-1992), 66 cases of IDDM in the 0- to 29-year-old age-group were identified. The completeness of ascertainment was 100% for the combined sources. Age-adjusted (world-standardized) incidence rates per 100,000 (95% confidence interval) were 9.52 (6.42-13.61), 6.72 (4.68-9.34), and 8.27 (6.42-10.58), respectively, for the age-groups 0-14, 15-29, and 0-29. The rates were higher for residents in urban areas. The number of children in the families of IDDM patients was significantly higher than in the reference population. CONCLUSIONS: Our data indicate the concordance of IDDM incidence rates with the North-Italian rates and a possible association of the disease with environmental factors. These factors might enhance the susceptibility to IDDM in genetically predisposed individuals.

Adolescent↗
PubMed1994

Expression of N-CAM by human renal cell carcinomas correlates with growth rate and adhesive properties.

In the present study we provide evidence for the involvement of N-CAM in the spreading of human renal cell carcinomas (RCC) through the interaction with the subendothelial matrix. We found that in tumor cell lines derived from human RCC the increase of growth rate and the loss of adhesiveness to inert substrate were accompanied by N-CAM expression and by the appearance of specific binding to endothelial heparan sulfate. Indeed, the adhesion of tumor cells to human endothelial cells and heparan sulfate in vitro was inhibited by monoclonal antibodies able to bind and inactivate N-CAM and was abrogated by endothelial cell treatment with heparitinase. Furthermore, when the renal epithelial cell line COS7 was transfected with a cDNA coding for N-CAM a significant increase in the ability to bind both endothelium and heparan sulfate in vitro was observed. Of note, HS complexed with epithelial growth factor could enhance the proliferation of RCC-derived tumor cells; this effect was also achieved by cross-linking of N-CAM at the surface of tumor cells, suggesting that N-CAM could transduce an activation signal across the cell membrane. This was also supported by the finding that N-CAM cross-linking induced a strong calcium mobilization from internal stores and opening of surface calcium channels in such tumor cells. N-CAM was detectable in vivo at the tumor site in the areas of active proliferation, as judged by the coexpression of Ki67 nuclear antigen, and heparan sulfate was present in the wall of blood vessels in the proximity of the tumor. These findings would suggest that growing kidney tumors might use N-CAM to bind the subendothelial matrix and complexed growth factors during tissue invasion and spreading.

Carcinoma, Renal Cell↗
PubMed1994

Inducible nitric oxide synthase modulates fibronectin production in the EA.hy926 cell line and cultured human umbilical vein endothelial cells.

We wished to test the hypothesis of a connection existing between inducible nitric oxide (NO) synthesis and production of extracellular matrix proteins in endothelial cells (EC). We recently reported that the inducible-NO pathway contributes to cytokine-induced enhancement of tumor cell (TC) adhesion to cultured vascular endothelium, independent of changes in E-selectin expression on endothelial cells (EC). We now show that inducible NO-synthase is involved in enhancing fibronectin production by EC. Indeed, fibronectin synthesis and secretion increased both in the EA.hy926 EC line and in human umbilical vein EC (HUVEC) after prolonged exposure to tumor necrosis factor-alpha (TNF-alpha) or interferon-gamma (IFN-gamma). This effect was reversed by the reported inhibitor of NO synthase N omega-nitro-L-arginine methyl ester (L-NAME 10(-5) M). The two cytokines exerted no additive effect, suggesting that they trigger a common metabolic pathway. NO production by cytokine-stimulated EC was dependent on the inducible NO-pathway, as demonstrated by studies of EC-dependent inhibition of platelet aggregation. This inhibition was also evident in calcium-free medium and was reversed by L-NAME and by two inhibitors of protein synthesis that are reported to block the inducible-NO synthase, such as dexamethasone (Dex 10(-7) M) and cycloheximide (Chx 10(-6) M). We conclude that modulation of the inducible NO-synthase may regulate matrix protein production by vascular endothelium during inflammation.

Amino Acid Oxidoreductases↗
PubMed1993

Transgenic mice expressing human CD14 are hypersensitive to lipopolysaccharide.

In vitro studies have previously shown that the myelomonocytic differentiation antigen CD14 is a receptor for a complex consisting of lipopolysaccharide (LPS) and LPS-binding protein. To investigate the role of CD14 in vivo and its relationship to induction of LPS-induced endotoxin shock, transgenic mice expressing human CD14 were produced. These mice express human CD14 strongly on the surface of their monocytes, neutrophils, and Thy-1(+) lymphocytes and are hypersensitive to LPS, as evidenced by their increased susceptibility to endotoxin shock. These results document the importance of CD14 in vivo as a primary mediator of this lethal syndrome. Furthermore, these mice provide an important model for testing the therapeutic effects of agents directed specifically against the human, as opposed to the murine, CD14 protein in preventing LPS-induced endotoxin shock.

Animals↗
PubMed1991

Recombinant interleukin-2 and lymphokine-activated killer cells in renal cancer patients: II. Characterization of cells cultured ex vivo and their contribution to the in vivo immunomodulation.

Peripheral blood mononuclear cells, obtained from patients with renal cell cancer and cultured ex vivo, exhibit high natural killer (NK) and lymphokine-activated killer (LAK) activity (also against allogeneic fresh tumour cells), which is transcribed into the hosts' immune status after reinfusion. Phenotypic analysis shows a slight increase in the percentage of CD56+ and CD8+ lymphocytes, while CD4+ lymphocytes decrease slightly. As a sign of activation an increase of cells expressing DR and CD25 antigens is observed. At the peripheral blood level, mononuclear cells show an increase, compared to basal values, of NK and LAK activity, especially at the end of the first infusion cycle. Phenotypic analysis of the patients' PBMC shows a decrease of CD3+CD4+ T lymphocytes and an increase of NK cells (CD3-CD56+CD16+) and of cells expressing activation markers (DR and CD25), particularly evident by the end of the second infusion cycle. Finally, in addition to the changes induced by IL-2 alone, reinfusion of incubated cells results in an activation of CD56+ and LeuM3+ cells.

Antigens, CD↗