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Biomedical subjects

A Aruffo

Publications and source records attributed to A Aruffo.

192 records · Page 11Linked to original sources
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↗
PubMed1990

Recognition by ELAM-1 of the sialyl-Lex determinant on myeloid and tumor cells.

Endothelial leukocyte adhesion molecule-1 (ELAM-1) is an endothelial cell adhesion molecule that allows myeloid cells to attach to the walls of blood vessels adjacent to sites of inflammation. ELAM-1 recognizes the sialyl-Lewis X (sialyl-Lex) determinant, NeuAc alpha 2-3Gal beta 1-4(Fuc alpha 1-3)GlcNAc-, a granulocyte carbohydrate also found on the surface of some tumor cell lines. Binding of myeloid cells to soluble ELAM-1 is inhibited by a monoclonal antibody recognizing sialyl-Lex or by proteins bearing sialyl-Lex, some of which may participate in humoral regulation of myeloid cell adhesion. Stimulated granulocytes also release an inhibitor of ELAM-1 binding that can be selectively adsorbed by monoclonal antibody to sialyl-Lex.

Amniotic Fluid↗
PubMed1990

CD44 is the principal cell surface receptor for hyaluronate.

CD44 is a broadly distributed cell surface protein thought to mediate cell attachment to extracelular matrix components or specific cell surface ligands. We have created soluble CD44-immunoglobulin fusion proteins and characterized their reactivity with tissue sections and lymph node high endothelial cells in primary culture. The CD44 target on high endothelial cells is sensitive to enzymes that degrade hyaluronate, and binding of soluble CD44 is blocked by low concentrations of hyaluronate or high concentrations of chondroitin 4- and 6-sulfates. A mouse anti-hamster hyaluonate receptor antibody reacts with COS cells expressing hamster CD44 cDNA. In sections of all tissues examined, including lymph nodes and Peyer's patches, predigestion with hyaluronidase eliminated CD44 binding.

Amino Acid Sequence↗
PubMed1989

Expression of cDNA clones encoding the thymocyte antigens CD1a, b, c demonstrates a hierarchy of exclusion in fibroblasts.

The CD1 gene family encodes at least three proteins: CD1a, CD1b, and CD1c, which are coexpressed on cortical thymocytes and a number of T cell leukemias. On thymocytes, CD1a forms noncovalent complexes with CD1b and CD1c, and a disulfide-linked heterodimer with CD8. This report describes the isolation and characterization of cDNA clones encoding the CD1a, CD1b, and CD1c Ag. Cotransfection of the cDNA was used to investigate the formation of intermolecular heterodimers by CD1a with other members of the CD1 gene family and with CD8. No intermolecular heterodimers were observed during transient expression in COS cells. However, an exclusion hierarchy was observed between members of the CD1 gene family when two or more members of the family were cotransfected into COS cells.

Amino Acid Sequence↗
PubMed1987

Molecular cloning of two CD7 (T-cell leukemia antigen) cDNAs by a COS cell expression system.

The human CD7 antigen (gp40) is a cell surface glycoprotein found on thymocytes and mature T-cells. It is one of the earliest antigens to appear on cells of the T-lymphocyte lineage, and the most reliable clinical marker of T-cell acute lymphocytic leukemia. This report describes the isolation and nucleotide sequence of a full length CD7 cDNA, and of a cDNA for an unusual intron-bearing precursor. The DNA sequence of the clone predicts a highly glycosylated membrane protein with homology to members of the immunoglobulin superfamily, and no relationship to known oncogenes. Over-expression of CD7 RNA was observed in only one T-cell tumor line, and genomic DNA rearrangement was not observed in any lines. Prompted by a recent suggestion that CD7 plays a role in IgM binding, COS cells expressing CD7 were tested and found not to bind IgM or IgM immune complexes.

Amino Acid Sequence↗
PubMed1987

Molecular cloning of the CD2 antigen, the T-cell erythrocyte receptor, by a rapid immunoselection procedure.

A cDNA encoding the CD2 antigen has been isolated by a highly efficient technique based on transient expression in COS cells and adherence of cells expressing surface antigen to antibody-coated dishes. COS cells expressing a CD2 cDNA isolated by this method readily formed rosettes with sheep as well as human and other mammalian erythrocytes. Pretreatment of transfected COS cells with anti-CD2 antibody, or pretreatment of human erythrocytes with anti-LFA-3 antibody, abolished rosette formation.

Amino Acid Sequence↗
PubMed1987

Molecular cloning of a CD28 cDNA by a high-efficiency COS cell expression system.

CD28 (Tp44) is a human T-cell-specific homodimer surface protein that may participate in T-cell activation. We have isolated a cDNA clone encoding CD28 by a simple and highly efficient cloning strategy based on transient expression in COS cells. Central to this strategy is the use of an efficient method to prepare large plasmid cDNA libraries. The libraries are introduced into COS cells, where transient expression of surface antigen allows the isolation of cDNAs by way of monoclonal antibody binding. The CD28 cDNA encodes a highly glycosylated membrane protein with homology to the immunoglobulin superfamily and directs the production of a homodimer in transfected COS cells.

Amino Acid Sequence↗
PubMedDate not supplied

Comparison of a protein model with its X-ray structure: the ligand binding domain of E-selectin.

E- and P-selectin are cell adhesion molecules implicated in the early events of inflammation. Three-dimensional models of the lectin domains have been reported by us and others prior to the availability of X-ray structural information. The models have been used to outline the ligand binding site in the selectins and to identify residues critical for function. Recently, the crystal structure of E-selectin has been reported, and thus, comparison of our E-selectin model with the X-ray data is now possible. The comparison shows that the assumptions on which the modeling was based were generally correct and provides an instructive example for the opportunities and the limitations of comparative modeling.

Amino Acid Sequence↗