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R Volpes

Publications and source records attributed to R Volpes.

36 records · Page 2Linked to original sources
PubMed1992

Induction of intercellular adhesion molecule-1 (CD54) on human hepatoma cell line HepG2: influence of cytokines and hepatitis B virus-DNA transfection.

Human hepatocyte expression of intercellular adhesion molecule-1 (ICAM-1) (CD54) was studied in vitro by exposing the well differentiated human hepatoblastoma cell line HepG2 to various cytokines. In addition, hepatitis B virus (HBV)-DNA transfected HepG2 cells were also analysed. Expression of ICAM-1 on HepG2 cells was then revealed with an immunohistochemical procedure. Untreated HepG2 cells were unreactive, but showed strong cytoplasmic ICAM-1 immunoreactivity after treatment with interferon-gamma (IFN-gamma). This induction was completely inhibited by addition of a neutralizing antibody directed to IFN-gamma. IL-1, IL-6, tumour necrosis factor-alpha (TNF-alpha) and IFN-alpha, used alone or in combination, did not induce ICAM-1 expression, neither did they inhibit the IFN-gamma-induced expression of this adhesion molecule on HepG2 cells. Untreated hepatitis B virus-DNA transfected HepG2 cells expressed membranous ICAM-1. These results indicate that IFN-gamma is the main cytokine trigger for ICAM-1 expression on HepG2 cells, suggesting that in areas of liver inflammation this adhesion molecule is up-regulated on hepatocytes by locally released IFN-gamma. In addition, expression of ICAM-1 by hepatitis B virus-DNA transfected HepG2 cells suggests other, still unknown, triggering mechanisms in the induction of such adhesion molecules, for instance gene activation by viral genome, or autocrine virus-induced hepatocellular cytokine production.

Carcinoma, Hepatocellular↗
PubMed1992

In situ immunohistochemical analysis of cell adhesion molecules on human corneal endothelial cells.

Interaction of leucocytes with human corneal endothelial cells (HCECs) can be observed in several clinicopathological conditions, such as uveitis, keratitis, and corneal graft rejection. Since leucocyte-endothelial cell interactions involve various adhesion receptors we have analysed the expression and distribution pattern of the neural cell adhesion molecule (NCAM), the intercellular adhesion molecule-1 (ICAM-1), the vascular cell adhesion molecule-1 (VCAM-1), the endothelial leucocyte adhesion molecule-1 (ELAM-1), and the cluster of differentiation antigen-44 (CD44) on flat preparations of normal and organ-cultured HCECs. NCAM and ICAM were constitutively expressed on HCECs whereas VCAM-1, ELAM-1, and CD44 were absent from normal HCECs. However flat mounts of HCECs from organ-culture preserved corneas showed a mosaic-like distribution pattern of VCAM-1 and ELAM-1 positive cells and garland-like clusters of CD44 positive cells. We suggest that modulation of ELAM-1, VCAM-1, and CD44 expression on HCECs may contribute to the regulation of leucocytes-HCECs interaction in the case of anterior segment inflammation.

Aged↗
PubMed1991

Distribution of the VLA family of integrins in normal and pathological human liver tissue.

The "very late activation" (VLA) subgroup of the integrin superfamily of adhesion molecules plays a central role in cell-cell and cell-matrix interactions. The six different VLA dimers known so far consist of a common beta subunit and a variable alpha (1 to 6) subunit. They serve as receptors for laminin, collagen, and fibronectin or function as adhesion molecules for leukocytes and are therefore of great significance in embryogenesis, growth and repair, and in leukocyte recirculation. The distribution of the common beta and the variable alpha chains of the VLA were studied in normal, inflammatory, and cholestatic liver biopsy samples. In normal liver tissue, vascular endothelia express alpha 1, 2, 3, 5, and 6; bile duct epithelium alpha 2, 3, 5, and 6; connective tissue stroma alpha 1 and 2; hepatocytes alpha 1 and 5; sinusoidal lining cells alpha 1, 2, and 5; and mononuclear cells alpha 4. Whereas bile ducts and vascular endothelia do not show relevant changes in alpha chain expression in liver diseases, hepatocytes de novo express membranous alpha 3 and 6 in inflammatory liver diseases. In view of the role of the VLA-3 and VLA-6 as laminin receptors, this finding is in line with the production of laminin in active liver disease. Moreover, de novo expression of "bile duct type" alpha 2, 3, and 6 on periportal hepatocytes in cholestatic liver disease likely illustrates a phenotypic switch of hepatocytes towards bile duct epithelium during cholestasis.

Antibodies, Monoclonal↗
PubMed1991

Expression of interferon-gamma receptor in normal and pathological human liver tissue.

Using in situ immunohistochemistry and a specific monoclonal antibody (mcab R1G10), we analyzed the expression of the human interferon-gamma receptor (HuIFN-gamma R) and its topographical distribution in normal liver biopsies and in biopsies with various inflammatory liver diseases. In normal liver tissue, mcab R1G10 reacted weakly with sinusoidal and vascular endothelial cells, while hepatocytes were distinctly negative. In pathological conditions, mcab R1G10 produced membranous, cytoplasmic and/or perinuclear staining of hepatocytes, in a topographical distribution which varied according to the type of liver disease. In acute hepatitis, R1G10-positive hepatocytes were diffusely distributed throughout the liver parenchyma, and showed strong cytoplasmic, as well as membranous and perinuclear reactivity. In chronic persistent hepatitis, weak membranous staining was found on a number of scattered hepatocytes in acinar zone 1, with more pronounced expression on single hepatocytes in acinar zone 3. In chronic active hepatitis and in active cirrhosis, a diffuse weak membranous reactivity throughout the liver parenchyma was accompanied by enhanced R1G10 expression in areas of inflammation in acinar zone 1. With immunoelectronmicroscopy, R1G10 reactivity was found on the peripheral cell membrane and on the microvillous canalicular cell membrane of hepatocytes in a strikingly discontinuous manner. In the cytoplasm, the reaction product was detected on the cisternae of the rough endoplasmic reticulum and on small vesicles which were especially abundant in the perinuclear area. Our results demonstrate the absence of HuIFN-gamma R on hepatocytes in the normal liver, and its de novo expression during inflammatory liver disease. These findings indicate that hepatocytes, by displaying the HuIFN-gamma R, may act as target cells for the immunoregulatory action of IFN-gamma during liver inflammation.

Biopsy, Needle↗
PubMed1991

Memory T cells represent the predominant lymphocyte subset in acute and chronic liver inflammation.

T cells can be divided into two main phenotypic subpopulations-i.e., the CD45RA-positive (2H4-positive) "naive" subset and the CD45RO-positive (UCHL1-positive) "memory" subset. In light of this recent functional reinterpretation of T-lymphocyte subpopulations, we reinvestigated the composition of the inflammatory infiltrate in liver biopsy specimens from patients with acute and chronic hepatitis. In normal liver, the few scattered mononuclear cells present in portal tracts and in the intralobular parenchyma consisted of both CD45RA-positive (2H4-positive) naive and CD45RO-positive (UCHL1-positive) memory T cells. In inflammatory liver diseases, portal tract and periportal and intralobular areas of inflammation consisted virtually only of CD45RO-positive (UCHL1-positive) memory T cells, which strongly expressed the CDw29 (4B4) antigen, and the adhesion molecules LFA-1, CD2, LFA-3, CD44 and VLA-4 and the activation marker human leukocyte antigen-DR. These results indicate that activated memory T cells represent the predominant subpopulation of lymphocytes in areas of liver inflammation. Memory T cells strongly express various homing receptors and adhesion molecules, which probably allow them to accumulate at inflammatory sites and to strengthen interaction with target cells. Furthermore, the increased number of memory T cells with enhanced interferon-gamma production in areas of liver inflammation may contribute to the maintenance and up-regulation of immune responses occurring in inflammatory liver diseases.

Acute Disease↗
PubMed1991

Lymphocyte trafficking in inflamed liver.

Cell-mediated immune reactions occurring in liver diseases involve infiltration of inflammatory cells into the hepatic parenchyma. Almost nothing is known about cellular and molecular mechanisms regulating this leukocyte traffic during the afferent and efferent arms of the hepatic immune response. This overview emphasizes that various liver parenchymal cells appear to participate actively in the development of the inflammatory response.

Antigens, CD↗
PubMed1991

Dendritic cells and the liver.

In comparison to other cells involved in the hepatic immune response, dendritic cells in human liver tissue have received remarkably little attention. In view of their presence in normal liver, and their multiple immunological functions, it can be anticipated that dendritic cells are involved in viral, autoimmune and rejection immune responses of the human liver.

Animals↗
PubMed1991

Distribution of very late activation integrins in the human cornea. An immunohistochemical study using monoclonal antibodies.

There is growing evidence that cellular adhesion mechanisms characterized by cell-cell and cell-matrix interactions are a fundamental process in the immunobiology of the cornea. Interactions with various extracellular matrix components are mediated by the very late activation (VLA) subgroup of the integrin superfamily of adhesion molecules. The six different VLA dimers known thus far consist of a common beta 1 subunit and a variable alpha (1 to 6) subunit. They serve as receptors for laminin (alpha 3 and alpha 6), collagen (alpha 2 and alpha 3), and fibronectin (alpha 4 and alpha 5). Using in situ immunohistochemistry and monoclonal antibodies, the distribution of the common beta 1 and the variable alpha-chains of VLA molecules was studied in normal human cornea and in cases with scarring or subepithelial/retrocorneal fibrous tissue. Epithelial cells were VLA-beta 1 and VLA-alpha 2, -alpha 3, -alpha 4, -alpha 5, and -alpha 6 positive. This is consistent with their intercellular adhesion and may aid in their attachment to the basement membrane which is composed of collagen, laminin, and fibronectin. Keratocytes in normal stroma expressed only the common beta 1-chain and no detectable alpha-chains. In regions of scar or fibrous tissue, however, an upregulated expression of the alpha-chains was detected. The VLA- alpha 1, -alpha 3, -alpha 4, and -alpha 5 were expressed in young fibrous tissue; in older lesions, VLA- alpha 1, -alpha 2, -alpha 3, -alpha 4, and -alpha 5 could be detected. The corneal endothelium showed a strikingly strong positivity for all VLA integrins.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗
PubMed1990

Immunohistochemical study of adhesion molecules in liver inflammation.

Using monoclonal antibodies and in situ immunohistochemistry, we studied the distribution of "accessory" adhesion molecules (i.e., intercellular adhesion molecule-1 and leukocyte function-associated antigen-3) in 114 liver biopsy specimens with various inflammatory liver diseases and in 12 control liver biopsy samples without inflammation. The distribution of these adhesion molecules was compared with the presence on inflammatory cells of their natural ligands, lymphocyte function-associated antigen-1 and cluster of differentiation antigen-2, respectively. In normal liver, intercellular adhesion molecule-1 and leukocyte function-associated antigen-3 reacted weakly with sinusoidal lining cells, portal vessel endothelium and scattered mononuclear inflammatory cells, whereas hepatocytes were constantly negative. In contrast, all 114 biopsy samples of acute or chronic liver diseases revealed strong expression of intercellular adhesion molecule-1 and leukocyte function-associated antigen-3 on sinusoidal lining cells and on hepatocytes in areas of inflammation. Hepatocellular membrane positivity resulted in a "honeycomb pattern" of staining , which was panacinar in acute hepatitis and focal in chronic persistent or aggressive hepatitis. In various other chronic liver diseases, a multifocal periportal and intraacinar honeycomb pattern was detected. In all cases, a close topographical correlation was found between hepatocellular expression of intercellular adhesion molecule-1 and leukocyte function-associated antigen-3 on one hand and the presence of inflammatory cells expressing lymphocyte function-associated antigen-1 and cluster of differentiation antigen-2 on the other.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗
PubMed1990

Hepatic expression of intercellular adhesion molecule-1 (ICAM-1) in viral hepatitis B.

The in situ distribution patterns of intercellular adhesion molecule-1 and human leukocyte antigen-DR antigens were studied in serial sections of 61 liver biopsy specimens from patients with hepatitis B virus infection using immunohistochemical techniques. In addition, the topographical relationship between the display of HBcAg on one hand and the expression of intercellular adhesion molecule-1 by hepatocytes on the other was analyzed with a double-staining immunohistochemical procedure in 14 selected liver biopsy samples showing chronic persistent or chronic active hepatitis and signs of active hepatitis B virus replication as reflected by the presence of variable amounts of HBcAg in a nuclear or cytoplasmic pattern of immunoreactivity. Coexpression of intercellular adhesion molecule-1 and human leukocyte antigen-DR antigens by hepatocytes correlated positively with the site and extent of the inflammatory infiltrate, which was composed of lymphocytes expressing lymphocyte function-associated antigen-1. In healthy HBsAg-positive carriers without inflammatory liver disease, no intercellular adhesion molecule-1 or human leukocyte antigen-DR expression was found on hepatocytes; in acute hepatitis, intercellular adhesion molecule-1 and human leukocyte antigen-DR were strongly expressed throughout the liver parenchyma on liver cell membranes and on sinusoidal lining cells. In chronic persistent and chronic active hepatitis and in active cirrhosis, intercellular adhesion molecule-1 and human leukocyte antigen-DR showed membranous positivity on focal clusters of hepatocytes in areas of periportal or intraacinar inflammation.(ABSTRACT TRUNCATED AT 250 WORDS)

Autopsy↗
PubMed1990

Adhesive molecules in liver disease. Immunohistochemical distribution of thrombospondin receptors in chronic HBV infection.

The distribution of the thrombospondin-receptor was studied in 26 cases of inflammatory hepatitis B virus (HBV) related liver disease and twelve non-inflammatory controls using monoclonal antibody (mcab) OKM5. OKM5 reacted in all cases with sinusoidal lining cells, portal vessel endothelium, and scattered mononuclear inflammatory cells. In 16 of the 26 cases with inflammation, one or more clusters of OKM5 positive (OKM5+) hepatocytes were found in areas of periportal or intralobular inflammation, whereas the remaining ten cases did not show hepatocellular OKM5 reactivity. In all but one case, OKM5+ liver cells coexpressed HLA-DR-antigens, and in twelve cases cytotoxic/suppressor T-cells were enriched in the OKM5+/HLA-DR+ liver cell clusters, suggesting induction of OKM5 positivity by lymphokines released by nearby T-cells. In view of its role in cytoadherence, it is suggested that OKM5 expression by hepatocytes serves in the entrapment and retention of inflammatory cells thereby facilitating their activation. Furthermore, OKM5+/HLA-DR+ hepatocytes might trigger an autologous mixed lymphocyte reaction (AMLR), resulting in down-modulation of ongoing hepatic inflammatory responses.

Antibodies↗
PubMed1988

Anti-alpha interferon antibodies after alpha interferon treatment in patients with chronic viral hepatitis.

Thirty-five patients with chronic viral hepatitis (B, D or non A, non B), treated with alpha interferon were evaluated by a highly sensitive enzyme immunoassay for the presence of alpha interferon neutralizing antibodies before and after three months of treatment. Although 4 subjects (11.4%) became immunized against alpha interferon, treatment with the drug was successful in inhibiting viral replication in 3 of them. We conclude that the appearance of anti alpha interferon antibodies does not affect the effectiveness of the drug, and is therefore not worth monitoring.

Adolescent↗
PubMedDate not supplied

Pediatric liver transplantation: preliminary results at Istituto Mediterraneo Trapianti e Terapie ad Alta Specializzazione.

Between July 2003 and November 2004 14 pediatric liver transplantations (LTx) have been performed in 12 children using cadaveric donors. The primary diseases were as follows biliary atresia in 9 cases, whereas the other 3 children were affected by cystic fibrosis, Langherans cells histiocytosis, and hepatoblastoma, respectively. Median patient waiting time was 103 days (range, 2-158); no patient died while on the waiting list. Patients who underwent transplantation included 7 boys and 5 girls, ranging in age from 6 months to 14 years (median age, 5 years). Recipient median weight was 16 kg (range, 6-38). Donor median age was 19 years (range, 3-47), whereas donor median weight was 74 kg (range, 15-90). All children who underwent primary LTx were United Network for Organ Sharing (UNOS) status 2B. Of the 12 transplanted patients, 9 received a left lateral segment (LLS) from an in situ split liver, whereas 3 received a whole graft. Two children developed an episode of acute cellular rejection on the seventh postoperative day, which was treated successfully with a course of intravenous steroids for 3 days. After a median follow-up of 245 days, 10 children are alive but 2 children died due to primary nonfunction (PNF) on the second postoperative day and septic shock on the fifth postoperative day after retransplantation for acute hepatic artery thrombosis, respectively. One child who underwent retransplantation for hepatic artery thrombosis on the 31st postoperative day after primary LTx is currently alive. Evaluation of our initial data suggests that the split liver technique has the potential to meet the needs of pediatric LTx allowing grafting early in the course of the original disease and reducing waiting time.

Adolescent↗
PubMedDate not supplied

Acceptance of marginal liver donors increases the volume of liver transplant: early results of a single-center experience.

To expand the donor pool, clinicians are continually modifying criteria to accept organs, particularly those in the so-called expanded or marginal donor pool. The concept and definition of a marginal donors continues to evolve. The impact of their use is the result of a combination of donor and recipient factors. Most clinicians accept steatosis above 30%, donor age over 60 years, prolonged ischemia time, prolonged intensive care unit stay, hypernatremia, previous cardiac arrest, prolonged episodes of hypotension, large use of inotrope drugs, and elevated liver function tests as criteria for designation of a marginal organ. In June 2003, we started to use marginal donors each year tripling the number of transplants per year at our center.

Cadaver↗