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Abstract
Selectins are a family of three cell adhesion molecules (L-, E-, and P-selectin) specialized in capturing leukocytes from the bloodstream to the blood vessel wall. This initial cell contact is followed by the selectin-mediated rolling of leukocytes on the endothelial cell surface. This represents the first step in a cascade of molecular interactions that lead to leukocyte extravasation, enabling the processes of lymphocyte recirculation and leukocyte migration into inflamed tissue. The central importance of the selectins in these processes has been well documented in vivo by the use of adhesion-blocking antibodies as well as by studies on selectin gene-deficient mice. This review focuses on the molecular mechanisms that regulate expression and function(s) of the selectins and their ligands. Cell-surface expression of the selectins is regulated by a variety of different mechanisms. The selectins bind to carbohydrate structures on glycoproteins, glycolipids, and proteoglycans. Glycoproteins are the most likely candidates for physiologically relevant ligands. Only a few glycoproteins are appropriately glycosylated to allow strong binding to the selectins. Recently, more knowledge about the structure and the regulated expression of some of the carbohydrates on these ligands necessary for selectin binding has been accumulated. For at least one of these ligands, the physiological function is now well established. A novel and exciting aspect is the signaling function of the selectins and their ligands. Especially in the last two years, convincing data have been published supporting the idea that selectins and glycoprotein ligands of the selectins participate in the activation of leukocyte integrins.
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Affiliation(s)
- D Vestweber
- Institute of Cell Biology, Center of Molecular Biology of Inflammation, University of Münster, Münster, Germany
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52
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Dwir O, Shimron F, Chen C, Singer MS, Rosen SD, Alon R. GlyCAM-1 supports leukocyte rolling in flow: evidence for a greater dynamic stability of L-selectin rolling of lymphocytes than of neutrophils. CELL ADHESION AND COMMUNICATION 1998; 6:349-70. [PMID: 9865468 DOI: 10.3109/15419069809010793] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
L-selectin plays a major role in leukocyte traffic through lymph node high endothelial venules (HEV). We have investigated the role of GlyCAM-1, a major L-selectin ligand produced by HEV, in mediating leukocyte rolling under in vitro flow conditions. Purified GlyCAM-1 was found to support tethering and rolling in physiological shear flow of both human and murine L-selectin expressing leukocytes at an efficiency comparable to the HEV-derived L-selectin ligands termed peripheral node addressin (PNAd). Major dynamic differences between L-selectin rolling of peripheral blood T lymphocytes and neutrophils expressing similar L-selectin level were observed on GlyCAM-1. Lymphocytes established slower and more shear resistant rolling than neutrophils and could roll on GlyCAM-1 at shear stresses lower than the threshold values required for L-selectin-mediated neutrophil rolling. Notably, high stability of L-selectin rolling of lymphocytes requires intact cellular energy, although initial lymphocyte tethering to L-selectin ligands is energy-independent. By contrast, L-selectin mediated rolling of neutrophils is insensitive to energy depletion. The distinct dynamic behavior and energy-dependence of L-selectin rolling in different leukocytes suggest that L-selectin adhesiveness in shear flow is regulated in a cell-type specific manner. The greater stability of L-selectin rolling of lymphocytes on surface-adsorbed GlyCAM-1 may contribute to their selective recruitment at peripheral lymph nodes.
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Affiliation(s)
- O Dwir
- Department of Immunology, Weizmann Institute of Science, Rehovot, Israel
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53
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Abstract
Abstract
CD164 is a novel 80- to 90-kD mucin-like molecule expressed by human CD34+ hematopoietic progenitor cells. Our previous results suggest that this receptor may play a key role in hematopoiesis by facilitating the adhesion of CD34+ cells to bone marrow stroma and by negatively regulating CD34+hematopoietic progenitor cell growth. These functional effects are mediated by at least two spatially distinct epitopes, defined by the monoclonal antibodies (MoAbs), 103B2/9E10 and 105A5. In this report, we show that these MoAbs, together with two other CD164 MoAbs, N6B6 and 67D2, show distinct patterns of reactivity when analyzed on hematopoietic cells from normal human bone marrow, umbilical cord blood, and peripheral blood. Flow cytometric analyses revealed that, on average, 63% to 82% of human bone marrow and 55% to 93% of cord blood CD34+ cells are CD164+, with expression of the 105A5 epitope being more variable than that of the other identified epitopes. Extensive multiparameter flow cytometric analyses were performed on cells expressing the 103B2/9E10 functional epitope. These analyses showed that the majority (>90%) of CD34+ human bone marrow and cord blood cells that were CD38lo/− or that coexpressed AC133, CD90(Thy-1), CD117(c-kit), or CD135(FLT-3) were CD164(103B2/9E10)+. This CD164 epitope was generally detected on a significant proportion of CD34+CD71lo/− or CD34+CD33lo/− cells. In accord with our previous in vitro progenitor assay data, these phenotypes suggest that the CD164(103B2/9E10) epitope is expressed by a very primitive hematopoietic progenitor cell subset. It is of particular interest to note that the CD34+CD164(103B2/9E10)lo/−cells in bone marrow are mainly CD19+ B-cell precursors, with the CD164(103B2/9E10) epitope subsequently appearing on CD34lo/−CD19+ and CD34lo/−CD20+ B cells in bone marrow, but being virtually absent from B cells in the peripheral blood. Further analyses of the CD34lo/−CD164(103B2/9E10)+ subsets indicated that one of the most prominent populations consists of maturing erythroid cells. The expression of the CD164(103B2/9E10) epitope precedes the appearance of the glycophorin C, glycophorin A, and band III erythroid lineage markers but is lost on terminal differentiation of the erythroid cells. Expression of this CD164(103B2/9E10) epitope is also found on developing myelomonocytic cells in bone marrow, being downregulated on mature neutrophils but maintained on monocytes in the peripheral blood. We have extended these studies further by identifying Pl artificial chromosome (PAC) clones containing the CD164 gene and have used these to localize the CD164 gene specifically to human chromosome 6q21.
© 1998 by The American Society of Hematology.
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54
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Abstract
CD164 is a novel 80- to 90-kD mucin-like molecule expressed by human CD34+ hematopoietic progenitor cells. Our previous results suggest that this receptor may play a key role in hematopoiesis by facilitating the adhesion of CD34+ cells to bone marrow stroma and by negatively regulating CD34+hematopoietic progenitor cell growth. These functional effects are mediated by at least two spatially distinct epitopes, defined by the monoclonal antibodies (MoAbs), 103B2/9E10 and 105A5. In this report, we show that these MoAbs, together with two other CD164 MoAbs, N6B6 and 67D2, show distinct patterns of reactivity when analyzed on hematopoietic cells from normal human bone marrow, umbilical cord blood, and peripheral blood. Flow cytometric analyses revealed that, on average, 63% to 82% of human bone marrow and 55% to 93% of cord blood CD34+ cells are CD164+, with expression of the 105A5 epitope being more variable than that of the other identified epitopes. Extensive multiparameter flow cytometric analyses were performed on cells expressing the 103B2/9E10 functional epitope. These analyses showed that the majority (>90%) of CD34+ human bone marrow and cord blood cells that were CD38lo/− or that coexpressed AC133, CD90(Thy-1), CD117(c-kit), or CD135(FLT-3) were CD164(103B2/9E10)+. This CD164 epitope was generally detected on a significant proportion of CD34+CD71lo/− or CD34+CD33lo/− cells. In accord with our previous in vitro progenitor assay data, these phenotypes suggest that the CD164(103B2/9E10) epitope is expressed by a very primitive hematopoietic progenitor cell subset. It is of particular interest to note that the CD34+CD164(103B2/9E10)lo/−cells in bone marrow are mainly CD19+ B-cell precursors, with the CD164(103B2/9E10) epitope subsequently appearing on CD34lo/−CD19+ and CD34lo/−CD20+ B cells in bone marrow, but being virtually absent from B cells in the peripheral blood. Further analyses of the CD34lo/−CD164(103B2/9E10)+ subsets indicated that one of the most prominent populations consists of maturing erythroid cells. The expression of the CD164(103B2/9E10) epitope precedes the appearance of the glycophorin C, glycophorin A, and band III erythroid lineage markers but is lost on terminal differentiation of the erythroid cells. Expression of this CD164(103B2/9E10) epitope is also found on developing myelomonocytic cells in bone marrow, being downregulated on mature neutrophils but maintained on monocytes in the peripheral blood. We have extended these studies further by identifying Pl artificial chromosome (PAC) clones containing the CD164 gene and have used these to localize the CD164 gene specifically to human chromosome 6q21.
© 1998 by The American Society of Hematology.
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55
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Bowman KG, Hemmerich S, Bhakta S, Singer MS, Bistrup A, Rosen SD, Bertozzi CR. Identification of an N-acetylglucosamine-6-0-sulfotransferase activity specific to lymphoid tissue: an enzyme with a possible role in lymphocyte homing. CHEMISTRY & BIOLOGY 1998; 5:447-60. [PMID: 9710564 DOI: 10.1016/s1074-5521(98)90161-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
BACKGROUND The leukocyte adhesion molecule L-selection participates in the initial attachment of blood-borne lymphocytes to high endothelial venules (HEVs) during lymphocyte homing to secondary lymphoid organs, and contributes to leukocyte adhesion and extravasation in HEV-like vessels at sites of chronic inflammation. The L-selection ligands on lymph mode HEVs are mucin-like glycoproteins adorned with the unusual sulfated carbohydrate epitope, 6-sulfo sialyl Lewis x. Sulfation of this epitope on the N-acetylglucosamine (GlcNAc) residue confers high-avidity L-selection binding, and is thought to be restricted in the vasculature to sites of sustained lymphocyte recruitment. The GlcNAc-6-0 sulfotransferase that installs the sulfate ester may be a key modulator of lymphocyte recruitment to secondary lymphoid organs and sites of chronic inflammation and is therefore a potential target for anti-inflammatory therapy. RESULTS A GlcNAc-6-0-sulfotransferase activity was identified within porcine lymph nodes and characterized using a rapid, sensitive, and quantitative assay. We synthesized two unnatural oligosaccharide substrates, GlcNAc beta 1-->6Gal alpha-R and Gal beta 1-->4GlcNAc beta 1-->6Gal alpha-R, that incorporate structural motifs from the native L-selection ligands into an unnatural C-glycosyl hydrocarbon scaffold. The sulfotransferase incorporated greater than tenfold more sulfate into the disaccharide than the trisaccharide, indicating a requirement for a terminal GlcNAc. Activity across tissues was highly restricted to the HEVs within peripheral lymph node. CONCLUSIONS The restricted expression of the GlcNAc-6-0-sulfotransferase activity to lymph node HEVs strongly suggestions a role in the biosynthesis of L-selection ligands. In addition, similar sulfated epitopes are known to be expressed on HEV-like vessels of chronically inflamed tissues; indicating that this sulfotransferase may also contribute to inflammatory lymphocyte recruitment. We identified a concise disaccharide motif, GlcNAc beta 1-->6Gal alpha-R, that preserved both recognition and specificity determinants for the GlcNAc-6-0-sulfotransferase. The absence of activity on the trisaccharide Gal beta 1-->6Gal alpha-R indicates a requirement for a substrate with a terminal GlcNAc residue, suggesting that sulfation precedes further biosynthetic assembly of L-selection ligands.
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Affiliation(s)
- K G Bowman
- Department of Chemistry, University of California, Berkeley 94720, USA
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56
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Lister IM, Rasmussen LK, Johnsen LB, Møller L, Petersen TE, Sørensen ES. The primary structure of caprine PP3: amino acid sequence, phosphorylation, and glycosylation of component PP3 from the proteose-peptone fraction of caprine milk. J Dairy Sci 1998; 81:2111-5. [PMID: 9749374 DOI: 10.3168/jds.s0022-0302(98)75786-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Proteose-peptone component 3 is a phosphorylated glycoprotein that was isolated from the proteose-peptone fraction of caprine milk. By mass spectrometric analysis, amino acid sequencing, and polymerase chain reaction analysis, the primary structure has been determined and has been shown to contain 136 amino acids. Phosphorylations were identified at Ser30 and Ser41. A partial glycosylation was present at Thr16, and a N-linked glycosylation was present at Asn78. Galactosamine was the amino sugar detected at Thr16. Glucosamine and galactosamine were the amino sugars found in the carbohydrate group linked to Asn78. The caprine amino acid sequence exhibits 88% identity with the bovine proteose-peptone component 3 sequence. However, when compared with the bovine sequence, the caprine sequence contains an insertion of a serine residue at position 25.
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Affiliation(s)
- I M Lister
- Department of Molecular and Structural Biology, University of Aarhus, Denmark
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57
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Van den Steen P, Rudd PM, Dwek RA, Opdenakker G. Concepts and principles of O-linked glycosylation. Crit Rev Biochem Mol Biol 1998; 33:151-208. [PMID: 9673446 DOI: 10.1080/10409239891204198] [Citation(s) in RCA: 523] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The biosynthesis, structures, and functions of O-glycosylation, as a complex posttranslational event, is reviewed and compared for the various types of O-glycans. Mucin-type O-glycosylation is initiated by tissue-specific addition of a GalNAc-residue to a serine or a threonine of the fully folded protein. This event is dependent on the primary, secondary, and tertiary structure of the glycoprotein. Further elongation and termination by specific transferases is highly regulated. We also describe some of the physical and biological properties that O-glycosylation confers on the protein to which the sugars are attached. These include providing the basis for rigid conformations and for protein stability. Clustering of O-glycans in Ser/Thr(/Pro)-rich domains allows glycan determinants such as sialyl Lewis X to be presented as multivalent ligands, essential for functional recognition. An additional level of regulation, imposed by exon shuffling and alternative splicing of mRNA, results in the expression of proteins that differ only by the presence or absence of Ser/Thr(/Pro)-rich domains. These domains may serve as protease-resistant spacers in cell surface glycoproteins. Further biological roles for O-glycosylation discussed include the role of isolated mucin-type O-glycans in recognition events (e.g., during fertilization and in the immune response) and in the modulation of the activity of enzymes and signaling molecules. In some cases, the O-linked oligosaccharides are necessary for glycoprotein expression and processing. In contrast to the more common mucin-type O-glycosylation, some specific types of O-glycosylation, such as the O-linked attachment of fucose and glucose, are sequon dependent. The reversible attachment of O-linked GlcNAc to cytoplasmic and nuclear proteins is thought to play a regulatory role in protein function. The recent development of novel technologies for glycan analysis promises to yield new insights in the factors that determine site occupancy, structure-function relationship, and the contribution of O-linked sugars to physiological and pathological processes. These include diseases where one or more of the O-glycan processing enzymes are aberrantly regulated or deficient, such as HEMPAS and cancer.
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58
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Coddeville B, Girardet JM, Plancke Y, Campagna S, Linden G, Spik G. Structure of the O-glycopeptides isolated from bovine milk component PP3. Glycoconj J 1998; 15:371-8. [PMID: 9613824 DOI: 10.1023/a:1006973802139] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The heat-stable acid-soluble phosphoglycoprotein component PP3 was isolated from the bovine milk proteose peptone fraction by concanavalin A affinity chromatography. Glycopeptides from the ConA-bound fraction corresponding to the component PP3 were obtained by Pronase digestion and were separated by gel filtration into high and low-molecular-mass glycopeptides. In a previous work, we have investigated the structure of the N-glycans from the high-molecular-mass glycopeptides [Girardet et al. (1995) Eur J Biochem 234: 939-46]. Here, we describe the structure of the O-glycans from the low-molecular-mass glycopeptides. By combining methylation analysis, mass spectrometry, 400 MHz 1H-NMR spectroscopy and peptide sequence analysis, we show that the low-molecular-mass fraction contains several neutral glycopeptides. A mixture of the following three glycan structures linked to the Thr86 has been identified: GalNac alpha1-O-Thr, Gal(beta1-3)GalNAc alpha1-O-Thr and Gal(beta1-4)GlcNAc(beta1-6)[Gal(beta1-3)]GalNAc alpha1-O-Thr.
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Affiliation(s)
- B Coddeville
- Laboratoire de Chimie Biologique, Unité Mixte de Recherche du Centre National de la Recherche Scientifique no 111, Université des Sciences et Technologies de Lille, Villeneuve d'Ascq, France
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59
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Abstract
Abstract
L-selectin is a leukocyte cell-surface glycoprotein that mediates adhesive interactions between circulating cells and vascular endothelium. All endothelial ligands of L-selectin characterized to date are glycoproteins that require sulfation for activity and share reactivity with MECA 79, a monoclonal antibody that recognizes a sulfate-dependent epitope involved in L-selectin attachment. We have recently identified by functional assay a glycoprotein L-selectin ligand expressed on the human hematopoietic cell line KG1a. We report here that this ligand is not recognized by MECA 79 and that it retains binding activity after metabolic inhibition of sulfation by chlorate. A native membrane L-selectin ligand exhibiting sulfate-independent function has not been described previously. Identification of this novel ligand on a nonendothelial cell type suggests that structural determinants conferring L-selectin binding may vary in a cell- and tissue-specific manner.
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60
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Rudloff S, Kunz C. Protein and nonprotein nitrogen components in human milk, bovine milk, and infant formula: quantitative and qualitative aspects in infant nutrition. J Pediatr Gastroenterol Nutr 1997; 24:328-44. [PMID: 9138181 DOI: 10.1097/00005176-199703000-00017] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- S Rudloff
- Research Institute of Child Nutrition, Dortmund, Germany
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61
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Kraal G, Mebius RE. High Endothelial Venules: Lymphocyte Traffic Control and Controlled Traffic**This article was accepted for publication on 27 September 1996. Adv Immunol 1997. [DOI: 10.1016/s0065-2776(08)60746-4] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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62
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Salmi M, Jalkanen S. How do lymphocytes know where to go: current concepts and enigmas of lymphocyte homing. Adv Immunol 1997; 64:139-218. [PMID: 9100982 DOI: 10.1016/s0065-2776(08)60889-5] [Citation(s) in RCA: 147] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- M Salmi
- MediCity Research Laboratory, Turku University, Finland
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63
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Singer MS, Rosen SD. Purification and quantification of L-selectin-reactive GlyCAM-1 from mouse serum. J Immunol Methods 1996; 196:153-61. [PMID: 8841453 DOI: 10.1016/0022-1759(96)00106-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
GlyCAM-1 is an endothelial-derived mucin found in the conditioned medium of organ-cultured lymph nodes and in serum. It is a ligand for L-selectin, but also interacts with P and E-selectin. It may play a role in the modulation of leukocyte trafficking into secondary lymphoid tissues as well as chronic inflammatory sites. Here we report the development of an ELISA that quantifies GlyCAM-1 in complex biological fluids such as serum. The ELISA response is linear over a concentration range of 13-800 ng/ml. The level of GlyCAM-1 in mouse serum was found to be 1.3-1.6 micrograms/ml. Using mouse serum as starting material, we report a rapid and efficient purification scheme for the isolation of biologically active GlyCAM-1. This material may now be used to address the biological functions of GlyCAM-1 and to further define its structural features.
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Affiliation(s)
- M S Singer
- Department of Anatomy, University of California, San Francisco 94143-0452, USA
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64
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65
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Abstract
The selectins are carbohydrate-binding cell adhesion molecules acting in the vascular system. They mediate the docking of leukocytes to the blood vessel wall and the rolling of these cells along the endothelial cell surface. These adhesion phenomena initiate the entry of leukocytes into sites of inflammation as well as the migration of recirculating lymphocytes into secondary lymphoid tissues. Blocking selectin function with antibodies or oligosaccharides has proven to be beneficial in various animal models of inflammation and models of ischemia/reperfusion damage. This has raised much interest in the identification of the physiological ligands of the selectins. Several glycoprotein ligands have been identified, some of which can even be selectively isolated from cellular detergent extracts using a selectin as an affinity probe. Four of these "high affinity" ligands have been cloned. The structural requirements of their interaction with the selectins is discussed.
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Affiliation(s)
- D Vestweber
- Institute for Cell Biology, ZMBE, University of Münster, Germany
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66
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Affiliation(s)
- J M Girardet
- Laboratoire des BioSciences de l' Aliment associé a l'INRA, Université Henri Poincaré-Nancy, Nancy, France
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67
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Salmi M, Jalkanen S. Human vascular adhesion protein 1 (VAP-1) is a unique sialoglycoprotein that mediates carbohydrate-dependent binding of lymphocytes to endothelial cells. J Exp Med 1996; 183:569-79. [PMID: 8627168 PMCID: PMC2192471 DOI: 10.1084/jem.183.2.569] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The regulated interactions of leukocytes with vascular endothelial cells are crucial in controlling leukocyte traffic between blood and tissues. Vascular adhesion protein-1 (VAP-1) is a novel, human endothelial cell molecule that mediates tissue-selective lymphocyte binding. Two species (90 and 170 kD) of VAP-1 exist in lymphoid tissues. Glycosidase digestions revealed that the mature 170-kD form of VAP-1 expressed on the lumenal surfaces of vessels is a heavily sialylated glycoprotein. The sialic acids are indispensable for the function of VAP-1, since the desialylated form of VAP-1 no longer mediates lymphocyte binding. We also show that L-selectin is not required for binding of activated lymphocytes to VAP-1 under conditions of shear stress. The 90-kD form of VAP-1 was only seen in an organ culture model, and may represent a monomeric or proteolytic form of the larger species. These data indicate that L-selectin negative lymphocytes can bind to tonsillar venules via the VAP- 1-mediated pathway. Moreover, our findings extend the role of carbohydrate-mediated binding in lymphocyte-endothelial cell interactions beyond the known selectins. In conclusion, VAP-1 naturally exists as a 170-kD sialoglycoprotein that uses sialic acid residues to interact with its counter-receptors on lymphocytes under nonstatic conditions.
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Affiliation(s)
- M Salmi
- National Public Health Institute and MediCity Research Laboratory, University of Turku, Finland
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68
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Schleiffenbaum B, Fehr J. Regulation and selectivity of leukocyte emigration. THE JOURNAL OF LABORATORY AND CLINICAL MEDICINE 1996; 127:151-68. [PMID: 8636644 DOI: 10.1016/s0022-2143(96)90074-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- B Schleiffenbaum
- Department of Internal Medicine, University Hospital Zürich, Switzerland
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69
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Schedin PJ, Thackray LB, Malone P, Fontaine SC, Friis RR, Strange R. Programmed cell death and mammary neoplasia. Cancer Treat Res 1996; 83:3-22. [PMID: 8826639 DOI: 10.1007/978-1-4613-1259-8_1] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Affiliation(s)
- P J Schedin
- AMC Cancer Research Center, Lakewood, CO 80214, USA
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70
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Onrust SV, Hartl PM, Rosen SD, Hanahan D. Modulation of L-selectin ligand expression during an immune response accompanying tumorigenesis in transgenic mice. J Clin Invest 1996; 97:54-64. [PMID: 8550850 PMCID: PMC507062 DOI: 10.1172/jci118406] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Immune surveillance depends on lymphocyte access to tissue. Lymphocytes emigrate from blood when adhesion receptors such as L-selectin and the alpha 4 beta 7 integrin on these cells bind to ligands expressed on venular endothelium. Among transgenic mouse lines expressing an oncoprotein (Tag) in islet beta cells, some recognize Tag as nonself. In these mice, Tag expression elicits both beta cell hyperplasia with subsequent progression to tumors and lymphocytic infiltration. Endothelial ligands for L-selectin and alpha 4 beta 7 were upregulated in infiltrated islets in these transgenic mice. These ligands were not expressed in tumors, which were devoid of lymphocytic infiltration. In contrast, the adhesion molecules PECAM-1, ICAM-1, and VCAM-1 were expressed on endothelium in both noninfiltrated tumors and infiltrated islets. Thus, upregulation of expression of endothelial ligands for L-selectin and alpha 4 beta 7 may contribute to autoimmune infiltration. Repression of expression of these same ligands may be involved in the failure of tumor immunity.
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MESH Headings
- Animals
- Antigens, Surface/analysis
- Antigens, Viral, Tumor/genetics
- Antigens, Viral, Tumor/immunology
- Cell Adhesion Molecules/analysis
- Endothelium, Vascular/immunology
- Endothelium, Vascular/pathology
- Gene Expression Regulation, Developmental
- Hyperplasia
- Immune Tolerance
- Immunoglobulins/analysis
- Islets of Langerhans/immunology
- Islets of Langerhans/pathology
- L-Selectin/metabolism
- Ligands
- Membrane Proteins
- Mice
- Mice, Inbred C3H
- Mice, Transgenic
- Mucins/analysis
- Mucins/genetics
- Mucins/metabolism
- Mucoproteins/analysis
- Neovascularization, Pathologic
- Pancreatic Neoplasms/immunology
- Pancreatic Neoplasms/pathology
- RNA, Messenger/analysis
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Affiliation(s)
- S V Onrust
- Department of Anatomy, University of California, San Francisco 94143, USA
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71
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Puri KD, Finger EB, Gaudernack G, Springer TA. Sialomucin CD34 is the major L-selectin ligand in human tonsil high endothelial venules. J Cell Biol 1995; 131:261-70. [PMID: 7559783 PMCID: PMC2120586 DOI: 10.1083/jcb.131.1.261] [Citation(s) in RCA: 133] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Peripheral node addressin (PNAd) is a complex mixture of glycoproteins with L-selectin ligand activity that functions in lymphocyte homing. We have investigated the contribution of the sialomucin CD34 relative to other components of PNAd in lymphocyte tethering and rolling in in vitro laminar flow assays. PNAd was isolated with MECA-79 mAb-Sepharose from tonsillar stroma, and the CD34 component (PNAd,CD34+) and CD34-negative component (PNAd,CD34-) separated on CD34 mAb-Sepharose. Lymphocytes on the PNAd,CD34- fraction tether less efficiently, roll faster and are less resistant to shear detachment than on PNAd. The PNAd,CD34+ fraction constitutes about half the total functional activity. These studies show that CD34 is a major functional component of PNAd. Ligand activity in both the PNAd,CD34+ and PNAd,CD34- fractions is expressed on mucin-like domains, as shown with O-sialoglycoprotease. The CD34 component of PNAd has about four times higher tethering efficiency than total tonsillar CD34. CD34 from spleen shows no lymphocyte tethering. Although less efficient than the PNAd,CD34+ fraction from tonsil, CD34 from the KG1a hematopoietic cell line is functionally active as an L-selectin ligand despite lack of reactivity with MECA-79 mAb, which binds to a sulfation-dependent epitope. All four forms of CD34 are active in binding to E-selectin. KG1a CD34 but not spleen CD34 are active as L-selectin ligands, yet both lack MECA-79 reactivity and possess E-selectin ligand activity. This suggests that L-selectin ligands and E-selectin ligands differ in more respects than presence of the MECA-79 epitope.
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Affiliation(s)
- K D Puri
- Center For Blood Research, Harvard Medical School, Boston, MA 02115, USA
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72
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Abstract
L-selectin, a member of the selectin family of leukocyte-endothelial adhesion proteins, mediates the initial attachment of lymphocytes to lymph node high endothelial venules during lymphocyte recirculation. One of the endothelial-associated ligands for L-selectin is GlyCAM-1, a mucin-like glycoprotein, which presents novel sulfated, sialylated and fucosylated O-glycans. In order to understand the generation of these glycans, we have examined the biosynthesis of GlyCAM-1 in lymph node organ culture. Using peptide-specific antibodies, lectins, and recombinant L-selectin, we detected the following species of GlyCAM-1: unglycosylated (< 28 kDa); modified with GalNAc only (28-33 kDa); modified with sialic acid, fucose, and sulfate but lacking L-selectin reactivity (40-50 kDa); and mature (L-selectin-reactive) ligand (50-60 kDa). Pulse-chase labeling at 15 degrees C suggested that GalNAc is added in a pre-Golgi compartment. Treatment with brefeldin A almost completely blocked sulfation, indicating that this modification occurs in the trans-Golgi network. Two distinct sialylation events occurred in the presence of brefeldin A, while fucosylation was partially blocked. We conclude that sialylation precedes both fucosylation and sulfation during biosynthesis. This ordering will help to identify the critical acceptor structures recognized by lymph node glycosyltransferases and sulfotransferases.
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Affiliation(s)
- D Crommie
- Department of Anatomy and Program in Immunology, University of California, San Francisco 94143-0452, USA
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73
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Girard JP, Springer TA. High endothelial venules (HEVs): specialized endothelium for lymphocyte migration. IMMUNOLOGY TODAY 1995; 16:449-57. [PMID: 7546210 DOI: 10.1016/0167-5699(95)80023-9] [Citation(s) in RCA: 379] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
High endothelial venules (HEVs) are specialized postcapillary venules found in lymphoid tissues that support high levels of lymphocyte extravasation from the blood. Here, Jean-Philippe Girard and Timothy Springer highlight the unique properties of HEV endothelium, discuss the molecular mechanisms controlling HEV specialization and review evidence suggesting that HEVs could play an important role in the pathogenesis of chronic inflammatory diseases.
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Affiliation(s)
- J P Girard
- Laboratoire de Biologie Moléculaire Eucaryote (LBME) du CNRS, Toulouse, France
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74
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Smalheiser NR, Kim E. Purification of cranin, a laminin binding membrane protein. Identity with dystroglycan and reassessment of its carbohydrate moieties. J Biol Chem 1995; 270:15425-33. [PMID: 7797531 DOI: 10.1074/jbc.270.25.15425] [Citation(s) in RCA: 121] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Cranin was described in 1987 as a membrane glycoprotein expressed in brain and many other tissues, which binds laminin with high affinity in a calcium-dependent manner. Dystrophin-associated glycoprotein ("dystroglycan") is a laminin-binding protein cloned in 1992 whose relation to cranin has remained uncertain. Here we describe the purification of cranin to homogeneity from sheep brain, show cranin to be a form of dystroglycan, and localize the N terminus of beta-dystroglycan to amino acid residue 654. We find that brain alpha-dystroglycan is tightly associated with membranes, and localizes to regions of synaptic contact as assessed by immunocytochemistry of rat cerebellum. Brain alpha-dystroglycan expresses high mannose/hybrid N-linked saccharides, terminal GalNAc residues, and the HNK-1 epitope. Although dystroglycan has previously been presumed to be a proteoglycan, the amino acid sequence, pI, O-sialoglycoprotease susceptibility, lectin-binding profile, and laminin-binding properties of brain dystroglycan are more typical of mucin-like proteins. Furthermore, using CHO mutant cell lines deficient in xylosyltransferase and galactosyltransferase I, which are required for glycosaminoglycan biosynthesis, it is shown that chondroitin sulfate and heparan sulfate are not critical for laminin binding, and indeed are apparently not expressed at all in dystroglycan from CHO cells.
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Affiliation(s)
- N R Smalheiser
- Department of Pediatrics, University of Chicago, Illinois 60637, USA
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75
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Groenen MA, Dijkhof RJ, van der Poel JJ. Characterization of a GlyCAM1-like gene (glycosylation-dependent cell adhesion molecule 1) which is highly and specifically expressed in the lactating bovine mammary gland. Gene X 1995; 158:189-95. [PMID: 7607540 DOI: 10.1016/0378-1119(95)00138-v] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
A bovine cDNA library, derived from the mammary gland of a lactating cow, was screened for identifying transcripts that specifically occur during lactation by means of differential hybridisation. Several of the clones isolated by this procedure shared 55 and 57% similarity with the mouse and rat glycosylation-dependent cell adhesion molecule 1 (GlyCAM1) cDNAs, respectively. Although the mouse and cattle proteins showed an overall similarity of only 41%, two specific regions of the proteins showed 83 and 81% similarity, respectively. The bovine protein also showed 55% similarity with a small protein isolated from the whey fraction of camel milk. Northern blot analysis showed that high-level expression of this gene was only observed in the mammary gland of lactating cows. The complete gene was isolated from a bovine genomic library and its organisation was determined. The gene was 2.5 kb in length and split into four exons. The size and organization of the gene as well as the position of the introns was identical to that of the mouse GlyCAM1 gene. In accordance with the tissue-specific expression of this gene in the mammary gland of lactating animals, potential mammary gland factor (MGF) binding sites were present in the promoter region of the gene. Based on the data presented in this study it is highly likely that this gene is the bovine homologue to the rat and mouse GlyCAM1 genes.
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Affiliation(s)
- M A Groenen
- Department of Animal Breeding, Agricultural University Wageningen, The Netherlands
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76
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Abstract
The interaction between neoplastic as well as normal T cells and vascular endothelial cells which is mediated by adhesion molecules play a key role in their trafficking, localization and infiltration. This brief article reviews our studies on the expression of adhesion molecules on leukemic cells isolated from patients with adult T cell leukemia (ATL) and HTLV-I-infected T cell line cells and on their adhesion to human umbilical vein endothelial cells (HUVEC). Fresh ATL cells expressed lymphocyte function-associated antigen-1 (LFA-1), but the expression of very late antigen-4 (VLA-4) and sialyl-Lewis(x) (SLex) was variable. Sialyl Lewis(a) (SLea) was not detected. Cell adhesion assays using HUVEC and adhesion-blocking antibodies revealed the consistent E-selectin-mediated adhesion and variable VLA-4-mediated adhesion of ATL cells to HUVEC. The studies on HTLV-I-infected T cell lines confirmed the above data. These results, together with the detection of E-selectin expression on the endothelium of the skin infiltrated with ATL cells, indicate that E-selectin-mediated adhesion is the major pathway for the adherence of ATL cells to endothelial cells. The possible role of such adhesion in the formation of skin lesions and other clinical manifestations of ATL which result from the infiltration of leukemic cells is discussed.
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Affiliation(s)
- T Uchiyama
- Research Center for Immunodeficiency Virus, Kyoto University, Japan
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77
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Johnsen LB, Sørensen ES, Petersen TE, Berglund L. Characterization of a bovine mammary gland PP3 cDNA reveals homology with mouse and rat adhesion molecule GlyCAM-1. BIOCHIMICA ET BIOPHYSICA ACTA 1995; 1260:116-8. [PMID: 7999787 DOI: 10.1016/0167-4781(94)00195-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A full length PP3 (Proteose-Peptone component 3) cDNA of 679 bp was isolated from a bovine mammary gland cDNA library. The cDNA encodes a signal peptide of 18 amino acids followed by the mature PP3 sequence of 135 amino acids. This polypeptide showed homology with mouse and rat GlyCAM-1 (Glycosylation dependent Cell Adhesion Molecule 1) a protein which has been shown to act as a ligand for lymphocytes. The similarity was most profound between the signal peptides and three short regions of the mature polypeptides. Additionally structural conservation was predicted by computer analysis in the shape of a C-terminal amphipathic helix. PP3 was found to be expressed in mammary gland but not in peripheral lymph nodes, Peyer's pathes, lung, spleen, heart, and muscle.
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Affiliation(s)
- L B Johnsen
- Protein Chemistry Laboratory, University of Aarhus, Denmark
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78
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Abstract
Understanding the cascade of gene expression and subsequent protein interactions that result both in the death of secretory mammary epithelium and the remodeling and renewal of the mammary gland for another cycle of lactation poses significant challenges (see Chapters 7 and 8, this volume). The complexity of mammary gland involution warrants caution in sorting through the various potential regulators and executors of apoptotic cell death in the mammary gland. As demonstrated by the number of remodeling enzymes expressed during involution, the relationship between mammary epithelium and its related mesenchyme is important for maintenance of differentiated function (Barcellos-Hoff et al., 1989; Streuli et al., 1991). Components of the extracellular matrix may play the role of survival factors, or may provide a source of factors, as a reserve of matrix-bound growth factors, necessary for survival of the secretory epithelium. Perturbation of this interaction alters mammary-specific differentiation gene expression, for example, production of milk proteins (Parry et al., 1987; Strange et al., 1991; Talhouk et al., 1992). Thus, alteration of the interaction between epithelium and its associated mesenchyme, which is an integral part of mammary involution, may also play a role in epithelial cell death. However, the epithelial-mesenchymal interactions that are the determining features in either mediating or modulating this cell death are just beginning to be defined. Stimuli that alter differentiated function may also induce apoptotic cell death of the epithelium but may have no physiological correlate. They may, however, have significant application in prevention or control of breast neoplasia.
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Affiliation(s)
- R Strange
- Division of Laboratory Research, AMC Cancer Research Center, Lakewood, Colorado 80214, USA
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79
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Girard JP, Springer TA. Cloning from purified high endothelial venule cells of hevin, a close relative of the antiadhesive extracellular matrix protein SPARC. Immunity 1995; 2:113-23. [PMID: 7600298 DOI: 10.1016/1074-7613(95)90083-7] [Citation(s) in RCA: 132] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
High endothelial venules (HEV) in lymphoid tissues support high levels of lymphocyte extravasion from the blood. We purified high endothelial cells from human tonsils by immunomagnetic selection with MECA-79 MAb to construct an HEV cDNA library. Differential screening of this library using cDNA probes from HEV (plus) or flat-walled vessel (minus) endothelial cells allowed us to characterize a novel human cDNA expressed to high levels in HEV. The cDNA encodes a secreted acidic calcium-binding glycoprotein of 664 aa residues, designated hevin, exhibiting 62% identity with the antiadhesive extracellular matrix protein SPARC, over a region of 232 aa spanning more than four fifths of the SPARC coding sequence. The primary structure and sequence of hevin and similar to SPARC-like proteins from rat and quail, called SC1 or QR1. Hevin could contribute to the induction or maintenance of features of the HEV endothelium that facilitate lymphocyte migration.
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Affiliation(s)
- J P Girard
- Center for Blood Research, Harvard Medical School, Boston, Massachusetts 02115, USA
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80
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Abstract
The selectins initiate many critical interactions among blood cells. The volume of information and diversity of opinions on the nature of the biologically relevant ligands for selectins is remarkable. This review analyzes the matter and suggests the hypothesis that at least some of the specificity may involve recognition of "clustered saccharide patches."
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Affiliation(s)
- A Varki
- Glycobiology Program, Cancer Center, University of California, San Diego, La Jolla 92093
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81
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Welply JK, Keene JL, Schmuke JJ, Howard SC. Selectins as potential targets of therapeutic intervention in inflammatory diseases. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1197:215-26. [PMID: 7518254 DOI: 10.1016/0304-4157(94)90006-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- J K Welply
- Monsanto Corporation, Department of Immunology, St. Louis, MO 63167
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82
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Abstract
The selectins are three related receptors that initiate rolling of leukocytes on activated platelets or endothelium through Ca(2+)-dependent recognition of cell surface carbohydrates. Cell adhesion may be enhanced by a limited number of membrane glycoproteins that present high affinity carbohydrate ligands to specific selectins. The synthesis and surface display of the selectins is normally tightly controlled, but inappropriate expression may contribute to inflammatory disorders. Recent in vivo studies confirm the importance of the selectins in both physiological and pathological leukocyte recruitment.
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Affiliation(s)
- R P McEver
- WK Warren Medical Research Institute, University of Oklahoma Health Sciences Center, Oklahoma City
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