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M P Bevilacqua

Publications and source records attributed to M P Bevilacqua.

At least 19 recordsLinked to original sources
PubMed1999

Secretory leukocyte protease inhibitor prevents allergen-induced pulmonary responses in animal models of asthma.

Secretory leukocyte protease inhibitor (SLPI) is a naturally occurring protein of human airways that exhibits broad spectrum inhibitory activity against mast cell and leukocyte serine proteases implicated in asthma pathology. To assess the potential therapeutic utility of SLPI in this disorder, its effects on antigen-induced pulmonary responses were evaluated. In Ascaris-sensitized sheep, SLPI (3 mg) administered by aerosol daily for 4 days, with the final dose 0.5 h before antigen challenge, reduced the areas under the curve for early- and late-phase bronchoconstriction (73 and 95%, respectively; p <.05 versus control responses). SLPI also inhibited the development of airway hyperresponsiveness to carbachol (84%, p <. 05 versus control response) measured 24 h after antigen challenge. In ovalbumin-sensitized guinea pigs, intratracheal administration of SLPI daily for 3 days, with the final dose 1 h before antigen challenge, inhibited the development of airway hyperresponsiveness to histamine with an ED50 of <0.05 mg/kg. Prolonged pharmacodynamic activity of SLPI was observed in both species. In a murine model of atopic asthma, SLPI inhibited leukocyte influx into the airways after chronic allergen challenge. SLPI administered to sheep by the predosing protocol described above also prevented the antigen-induced decrease of tracheal mucus velocity (p <.05). In addition, a single aerosol administration of SLPI (30 mg) to sheep 1 h after antigen challenge inhibited the subsequent late-phase bronchoconstriction and development of hyperresponsiveness and reversed the stimulated decrease in tracheal mucus velocity. These results suggest that SLPI may provide therapeutic intervention against the pathophysiology of asthma and its underlying pathology.

Aerosols↗
PubMed1997

Inhibition of colon carcinoma cell lung colony formation by a soluble form of E-selectin.

During metastasis, tumor cells adhere to vascular endothelia. E-selectin is an adhesive protein expressed by cytokine-activated endothelium that can support adhesion of colon cancer cells through the recognition of specific carbohydrate ligands. Using a series of colon carcinoma cell lines that displayed E-selectin adhesiveness and an increased metastatic capacity in cytokine-treated mice, we examined possible inhibition of cytokine-dependent experimental lung metastasis by a soluble form of E-selectin, the recombinant fusion protein E-selectin-immunoglobulin. We found that E-selectin-immunoglobulin bound to the surfaces of HT-29 colon carcinoma cells and blocked the formation of cytokine-inducible experimental lung metastases; control L-selectin-immunoglobulin also bound to HT-29 cells but had no effect on tumor cell lung colonization. E-selectin-immunoglobulin was found to interfere with E-selectin-dependent adhesion of HT-29 cells to activated vascular endothelium and to block the retention of these cells in the lung, a process that implies tumor cell adhesive interactions with the host vasculature. Our results demonstrate that E-selectin-immunoglobulin inhibits adhesion and formation of lung metastases by colon carcinoma cells and suggest that impairment of tumor cell-endothelium adhesion might represent a therapeutic approach to the metastatic diffusion of tumors.

Animals↗
PubMed1995

Differential colon cancer cell adhesion to E-, P-, and L-selectin: role of mucin-type glycoproteins.

E-, P-, and L-selectin support the adhesion of leukocytes to the vessel wall through the recognition of specific carbohydrate ligands, which often contain sialylated, fucosylated lactosamines such as sialyl Lewis x [sLex; Neu5Ac alpha 2-3Gal beta 1-4(Fuc alpha 1-3)GlcNAc-]. E-selectin expressed by activated endothelium has been shown to support the adhesion of sLex-bearing colon cancer cells. In the present study, we examine the interactions of multiple colon cancer cell lines with all three selectins. Three colon cancer cell lines (LS 180, T84, and COLO 205) bound to recombinant purified E-, P-, and L-selectin. The colon cancer line COLO 320 bound to P- and L-selectin but not E-selectin; conversely, HT-29 cells bound E-selectin but not P- and L-selectin. Caco-2 showed little or no interaction with any of the three selectins. Treatment of the cells with O-sialoglycoprotease from Pasteurella haemolytica, an enzyme that selectively cleaves mucin-type O-linked glycoproteins, reduced binding to purified P- and L-selectin in all cases. In addition, recombinant soluble P- and L-selectin bound to affinity-purified mucins from all adherent tumor cell lines. Of the four tumor cell lines that interacted with E-selectin, O-glycoprotease treatment substantially diminished adhesion of LS 180 and T84, had little effect on COLO 205, and failed to inhibit the binding of HT-29. As predicted by these data, E-selectin showed substantial binding only to mucins purified from LS 180 and T84. These findings suggest that L- and P-selectin interact primarily with mucin-type ligands on colon cancers, whereas E-selectin can recognize both mucin and nonmucin ligands. Binding of the colon cancer lines to purified selectins correlates with their adhesion to activated endothelial cells (E-selectin-dependent), platelets (P-selectin-dependent), and neutrophils (L-selectin-dependent). These differential tumor cell-selectin interactions may influence metastatic spread and may also contribute to the observed variability in host response to tumor progression.

Animals↗
PubMed1995

Carbohydrate-protein interactions in vascular biology.

Carbohydrate-protein interactions participate in a wide variety of biological and pathological events. In recent years, particular attention has been paid to the carbohydrate-protein interactions that occur in vascular biology. Sialylated oligosaccharides are ligands of a structurally diverse group of proteins that include the selectins and members of the immunoglobulin superfamily. Various glycosaminoglycans can be recognized by an overlapping set of proteins that include two of the selectins and CD44. Emerging knowledge of carbohydrate-protein interactions in human pathophysiology are discussed.

Animals↗
PubMed1994

Inositol polyanions. Noncarbohydrate inhibitors of L- and P-selectin that block inflammation.

Selectins are cell adhesion molecules known to support the initial attachment of leukocytes to inflamed vascular endothelium through their recognition of carbohydrate ligands such as the tetrasaccharide sialyl Lewisx (Neu5Ac alpha 2-3Gal beta 1-4(Fuc alpha 1-3)GlcNAc-). In the present study, we describe the inhibition of L- and P-selectin function by inositol polyanions, simple 6-carbon ring structures that have multiple ester-linked phosphate or sulfate groups. In a purified component competition assay, binding of L- and P-selectin-Ig fusion proteins to immobilized bovine serum albumin-sialyl Lewisx neoglycoprotein was inhibited by inositol hexakisphosphate (InsP6, IC50 = 2.1 +/- 1.4 microM and 160 +/- 40 microM), by inositol pentakisphosphate (InsP5, IC50 = 1.4 +/- 0.2 and 260 +/- 40 microM), and by inositol hexakissulfate (InsS6, IC50 = 210 +/- 80 microM and 2.8 +/- 0.9 mM); E-selectin-Ig binding was unaffected. Inositol polyanions diminished the adhesion of LS180 colon carcinoma cells to plates coated with L- and P-selectin-Ig but not with E-selectin-Ig. Inositol polyanions blocked polymorphonuclear leukocyte (PMN) adhesion to COS cells expressing recombinant transmembrane P-selectin but not to those expressing E-selectin. In addition, inositol polyanions diminished PMN adhesion to activated endothelial cells under rotation-induced shear stress, a process known to require L-selectin function. In vivo, the effects of inositol polyanions were studied in two murine models of acute inflammation. Intravenously administered InsP6 (two doses of 40 mumol/kg) inhibited PMN accumulation in thioglycolate-induced inflammation (55 +/- 10% inhibition) and in zymosan-induced inflammation (61 +/- 4% inhibition). InsP5 and InsS6 also inhibited inflammation in these models, although higher doses were required for InsS6. In conclusion, inositol polyanions are noncarbohydrate small molecules that inhibit L- and P-selectin function in vitro and inflammation in vivo.

Animals↗
PubMed1994

Cytokine-induced beta-galactoside alpha-2,6-sialyltransferase in human endothelial cells mediates alpha 2,6-sialylation of adhesion molecules and CD22 ligands.

Sialic acids decorating blood and cell surface proteins can play important roles in various biological processes. The inflammatory cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin-1, as well as bacterial lipopolysaccharide, can activate vascular endothelium, increasing expression of several surface glycoproteins. Here we show that treatment of cultured human endothelial cells (HEC) with TNF-alpha, interleukin-1, or lipopolysaccharide causes increased expression of the enzyme beta-galactoside alpha-2,6-sialytransferase (alpha 2-6STN). TNF-alpha was most effective, inducing a 3.5-fold enhancement of cell-associated sialytransferase activity by 72 h. In addition, activated HEC secreted a large portion of the induced sialyltransferase activity into the medium. Analysis of labeled HEC showed both a relative and an absolute increase of alpha 2,6-linked sialic acid on N-linked oligosaccharides after TNF-alpha stimulation. This coincided with increased expression of endothelial glycoproteins bearing N-linked glycans with alpha 2,6-linked sialic acid detected by the lectin Sambucus nigra agglutinin. The cytokine-inducible endothelial cell adhesion molecules E-selectin, ICAM-1, and VCAM-1 are among these glycoprotein substrates for alpha 2-6STN. These changes also correlated with a substantial increase in binding sites for CD22 beta, a mammalian lectin known to recognize oligosaccharides carrying multiple copies of alpha 2,6-linked sialic acid. Northern analysis revealed increased levels of mRNA encoding alpha 2-6STN. Thus, activation of endothelial cells during inflammatory and immunological processes may induce alpha 2-6STN, which can participate in sialylation of other activation-dependent molecules.

Antigens, CD↗
PubMed1994

Endothelial-leukocyte adhesion molecules in human disease.

An effective host response to infection or tissue damage requires focal accumulation of leukocytes. Leukocyte adhesion to the vessel wall, a key step in this process, depends on the ordered expression of specific endothelial cell surface molecules. The endothelial molecules that support adhesion include selectins that recognize leukocyte cell surface glycoconjugates as well as members of the immunoglobulin superfamily that interact with leukocyte integrins. Although inflammation can occur with minimal damage to the vessel wall and surrounding tissues, control mechanisms sometimes appear to fail, and the inflammatory response itself becomes a significant clinical problem. In this review, we discuss endothelial-leukocyte adhesion molecules with particular emphasis on their expression and function in human disease. Pathophysiological processes presented include atherosclerosis, ischemia-reperfusion injury, acute lung injury, rheumatoid arthritis, and graft rejection. A more detailed description of the discovery and characterization of the key molecules appears in the antecedent article entitled "Endothelial-Leukocyte Adhesion Molecules".

Cell Adhesion↗
PubMed1993

Heparin oligosaccharides bind L- and P-selectin and inhibit acute inflammation.

Initial attachment of leukocytes to the vessel wall at sites of inflammation is supported by a family of carbohydrate-binding adhesion molecules called the selectins. Selectin ligands include sialyl-Lewis x (sLex, Neu5Ac alpha 2-3Gal beta 1-4[Fuc alpha 1-3]GlcNAc--) and related structures. We report here that defined heparin oligosaccharides interact with the selectins. Heparin chains containing four or more monosaccharide residues inhibited the function of L- and P-selectin, but not E-selectin, in vitro. In a competition enzyme-linked immunosorbent assay measuring inhibition of solution-phase selectin-Ig fusion proteins (selectin-Ig) binding to immobilized bovine serum albumin-sLex neoglycoprotein, a heparin-derived tetrasaccharide mixture inhibited 50% of L- and P-selectin-Ig binding (IC50) at 200 +/- 40 mumol/L and 850 +/- 110 mumol/L, respectively. A single hexasulfated tetrasaccharide (delta UA2S alpha 1-4GlcNS6S alpha 1-4IdoA2S alpha 1-4GlcNS6S) was particularly active against L- and P-selectin-Ig (IC50 = 46 +/- 5 mumol/L and 341 +/- 24 mumol/L). By comparison, the tetrasaccharide sLex was not inhibitory at concentrations up to 1 mmol/L. In cell adhesion assays, heparin tetrasaccharides reduced binding of neutrophils to COS cells expressing P-selectin but not to COS cells expressing E-selectin. They also blocked colon cancer cell adhesion to L- and P-selectin but not E-selectin. In a model of acute inflammation, intravenously administered heparin tetrasaccharides diminished influx of neutrophils into the peritoneal cavities of thioglycollate-treated mice. We conclude that heparin oligosaccharides, including non-anticoagulant tetrasaccharides, are effective L- and P-selectin inhibitors in vitro and have anti-inflammatory activity in vivo.

Acute Disease↗
PubMed1993

Endothelial-leukocyte adhesion molecules in inflammation and metastasis.

Vascular endothelium is an active tissue. In response to various mediators, it expresses specific cell surface glycoproteins that support the binding and extravasation of blood leukocytes. These events are essential for host defense against pathogens and for repair of tissue damage. Unfortunately, it appears that a number of blood borne tumor cells may be able to use the same adhesive structures to facilitate their metastasis. The development of agents designed to block the adhesion of leukocytes (or tumor cells) to the vessel wall may prove valuable in the treatment of a variety of human disease processes, including adult respiratory distress syndrome (ARDS), ischemic reperfusion injury, autoimmunity, and metastatic spread of cancer.

Carbohydrate Metabolism↗
PubMed1993

Endothelial-leukocyte adhesion molecules.

One decade ago, vascular endothelium was commonly considered a "non-stick" lining of blood vessels that functioned only to prevent blood coagulation and to separate the vascular space from tissues. By comparison to many other cell types, endothelial cells were thought to be less active, less complex, and less interesting. Since that time, research concerning the endothelium has expanded dramatically and produced a new image of the vascular lining as an active participant in a wide variety of pathophysiological processes, including inflammation and immunity. Nowhere has the excitement been more intense than in the study of the molecular mechanisms of leukocyte adhesion to endothelium. Recent efforts resulted in the identification, characterization, and cloning of multiple endothelial cell-surface glycoproteins that support adhesion through an interaction with specific ligands (or counter-receptors) on leukocytes. The selectins, two of which are found on endothelium and one on leukocytes, support adhesion through the recognition of carbohydrates. Endothelial members of the immunoglobulin superfamily including ICAM-1 and VCAM-1/INCAM-110 bind to leukocyte cell-surface integrins. In various combinations, these and other molecules support leukocyte adhesion to the vessel wall and extravasation, key steps in our response to infection and tissue injury.

Animals↗
PubMed1993

Selectins.

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Animals↗
PubMed1993

Higher-affinity oligosaccharide ligands for E-selectin.

A series of synthetic oligosaccharides based on sialyl Lewis x (sLex; Neu5Ac alpha 2-3Gal beta 1-4[Fuc alpha 1-3]GlcNAc) and sialyl Lewis a (sLea; Neu5Ac alpha 2-3Gal beta 1-3[Fuc alpha 1-4]GlcNAc) was used to study the binding interactions of selectins. E-selectin-immunoglobulin fusion protein (E-selectin-Ig) bound to immobilized bovine serum albumin (BSA)-neoglycoproteins containing sLex or sLea in a Ca(2+)-dependent manner. Solution-phase sLex tetrasaccharide blocked this interaction by 50% at a concentration of 750 +/- 20 microM (IC50). sLea was more effective (IC50 = 220 +/- 20 microM), while nonsialylated, nonfucosylated derivatives showed little or no activity at concentrations up to 1 mM. Attachment of an 8-methoxycarbonyloctyl aglycone in a beta linkage to the anomeric carbon of the GlcNAc of sLex or sLea increased their blocking activity nearly twofold. Finally, replacement of the 2-N-acetyl substituent of the GlcNAc by an azido or amino group resulted in substantial increases in activity, with the most potent inhibitor being amino substituted sLea, which was 36-fold more active (IC50 = 21 +/- 3 microM) than the reducing tetrasaccharide sLex. In contrast to results obtained with E-selectin-Ig, P-selectin-Ig binding to immobilized BSA-sLea was blocked modestly by most oligosaccharides at 1 mM, with no substantial differences among them. IC50 values of soluble oligosaccharides determined in competitive binding studies accurately predicted blocking of leukocyte adhesion to recombinant E-selectin-Ig and to cytokine-activated endothelium.

Carbohydrate Conformation↗
PubMed1992

Expression of sialyl-Lewis X, an E-selectin ligand, in inflammation, immune processes, and lymphoid tissues.

The carbohydrate structure sialyl-Lewis X (SLex) can function as a ligand for E-selectin, formerly known as endothelial leukocyte adhesion molecule-1 (ELAM-1). This study was performed to analyze the expression of SLex by leukocytes and other cell types in the context of inflammatory and immune processes. Human peripheral blood cells were examined by flow cytometry using monoclonal antibody CSLEX1 directed against SLex. Cell surface SLex was found in abundance on nearly all isolated polymorphonuclear leukocytes (PMN) and monocytes, and at low levels on a substantial portion (up to 40%) of natural killer cells. This moiety was expressed also on approximately 10% of peripheral blood T cells. Immunohistochemistry was performed on various human tissues involved in inflammatory or immune processes and on secondary lymphoid tissues. In acute appendicitis, endothelial cells of postcapillary venules expressed E-selectin, and most PMN, both within vessels and extravasated, expressed SLex. A substantial number of monocytes/macrophages in inflamed appendiceal, synovial, and dermal tissues also reacted with antibody CSLEX1; however, only rare tissue macrophages in uninflamed nonlymphoid sites showed expression of SLex. These observations are consistent with the concept that SLex on circulating PMN and monocytes functions as a ligand for endothelial E-selectin in the development of inflammatory reactions. SLex-positive lymphocytes also were seen, notably, T lymphocytes in inflamed skin. An unexpected finding was that the CSLEX1 antibody also reacted with venular endothelium in certain lymphoid tissues and in inflamed appendix, but not with endothelium in normal appendix. Whether the SLex antigen identified on endothelium represents de novo expression or passive adsorption remains to be determined.

Carbohydrate Metabolism↗
PubMed1991

Structure and chromosomal location of the gene for endothelial-leukocyte adhesion molecule 1.

Endothelial-leukocyte adhesion molecule 1 is a cell surface glycoprotein expressed by cytokine-activated endothelium that mediates the adhesion of blood neutrophils. Endothelial-leukocyte adhesion molecule 1 is a member of the selectin family of cell adhesion molecules each of which contain an amino-terminal lectin-like domain, followed by an epidermal growth factor-like domain and a variable number of short consensus repeats similar to those found in complement binding proteins. Genomic clones encoding the ELAM gene were isolated and the organization of the ELAM gene was determined. The gene, which is present in a single copy in the human genome, contains 14 exons spanning about 13 kilobases of DNA. The positions of exon-intron boundaries correlate with the putative functional subdivisions of the protein. Introns are found at similar positions in all of the six complement regulatory repeats, suggesting that these elements arose by internal gene duplication. A consensus TATAA element is located upstream of the transcriptional start site. The ELAM promoter contains an inverted CCAAT box and consensus NF-kappa B- and AP-1-binding sites. The ELAM gene was assigned to the q12 greater than qter region of human chromosome 1 by analysis of human-mouse hybrid cell lines. Two other members of the selectin gene family, the leukocyte adhesion molecule 1 (LAM-1, TQ1, LEC-CAM 1, or Leu-8) and the granule membrane protein 140 (GMP-140, PADGEM, or CD62) have been localized to the long arm of chromosome 1, as have the structurally related complement binding proteins, suggesting that these genes may share a common evolutionary history.

Amino Acid Sequence↗
PubMed1991

Tumor cell surface alpha 4 beta 1 integrin mediates adhesion to vascular endothelium: demonstration of an interaction with the N-terminal domains of INCAM-110/VCAM-1.

Hematogenous metastasis involves adhesive interactions between blood-borne tumor cells and the vessel wall. By the use of in vitro assays, the adhesion of human melanoma, osteosarcoma, and kidney carcinoma (but not colon carcinoma) cell lines was shown to involve the cytokine-inducible endothelial cell surface protein inducible cell adhesion molecule 110 (INCAM-110) and the alpha 4 beta 1 integrin, molecules normally involved in endothelial-leukocyte interactions. Tumor adhesion to human endothelial cell monolayers was increased 1.9- to 8.2-fold by endothelial activation with the cytokine tumor necrosis factor (TNF) and inhibited by the anti-INCAM-110 monoclonal antibody (mAb) E1/6. Each of these tumor cells expressed members of the beta 1 integrin family of adhesion molecules, and antibodies to the alpha 4 and beta 1 integrin subunits inhibited tumor-endothelial adhesion (48-87% inhibition). A cDNA encompassing the three N-terminal Ig-like domains of vascular cell adhesion molecule 1 (VCAM-1) encoded a protein recognized by the anti-INCAM-110 mAb E1/6 and, when captured onto plastic, supported melanoma cell adhesion by an alpha 4 integrin-dependent mechanism. In contrast to mAb E1/6, a second anti-INCAM-110 mAb Hu8/4 neither inhibited adhesion to activated endothelium nor bound the first three Ig-like domains of INCAM-110/VCAM-1. These data indicate that the adherence of several human tumors to activated endothelium is mediated by an interaction of alpha 4 beta 1 integrin and the N-terminal Ig-like domains of endothelial INCAM-110/VCAM-1. Tumor acquisition of the alpha 4 integrin subunit and endothelial expression of INCAM-110 may affect the frequency and distribution of metastasis.

Antibodies, Monoclonal↗
PubMed1991

Vascular and nonvascular expression of INCAM-110. A target for mononuclear leukocyte adhesion in normal and inflamed human tissues.

Inducible cell adhesion molecule 110 (INCAM-110), is a 110-kd adhesion receptor for lymphocytes and monocytes identified on cytokine-activated endothelium. Using immunoperoxidase techniques, little or no INCAM-110 was detected on endothelium in normal human tissues. In contrast, INCAM-110 was expressed in postcapillary venules in a variety of active inflammatory processes. In acute appendicitis, INCAM-110 was found coincident with strong expression of endothelial leukocyte adhesion molecule 1 (ELAM-1), a cytokine-inducible molecule that functions in neutrophil adhesion. However, in certain chronic inflammatory processes (eg, sarcoidosis), INCAM-110 was observed without simultaneous ELAM-1 expression. Anti-INCAM-110 antibody E1/6 also marked several extravascular cell types, including lymphoid dendritic cells, some tissue macrophages, synovial lining cells, and reactive mesothelial cells. These data suggest a role for endothelial INCAM-110 in the pathophysiology of both acute and chronic inflammatory reactions. Furthermore INCAM-110 may function as an adhesion molecule for mononuclear leukocytes in a variety of extravascular sites.

Acute Disease↗