Biomaterial Database

Monoclonal antibodies to leucosialin (CD43) induce homotypic aggregation of the human mast cell line HMC-1: characterization of leucosialin on HMC-1 cells. 1994

S Weber, and B Ruh, and E Dippel, and B M Czarnetzki

Department of Dermatology, Rudolf Virchow Clinics, Freie Universitaet Berlin, Germany.

CD43 (leucosialin, sialophorin) is the major sialoprotein of nearly all circulating leucocytes and has important biological activities in cellular differentiation and activation. Recently, the expression of CD43 has also been demonstrated on mast cells and basophils by flow cytometry. In order to further characterize mast cell/basophil leucosialin we have investigated CD43 on the human mast cell line HMC-1, the human basophilic precursor cell line KU-812, and the human promonocytic cell line U-937. The apparent molecular weights (MW) were 123,000 (HMC-1 and KU-812) and 144,000 (U-937) by Western blot analysis. Expression of CD43 on HMC-1 was down-regulated after stimulation with phorbol myristate acetate (PMA). Three monoclonal antibodies (mAb) specific for human CD43 induced homotypic mast cell line (HMC-1) aggregation in a semi-quantitative assay, a phenomenon that has not been described before with mast cells. Monoclonal antibodies specific for seven other surface antigens and an irrelevant mAb of the same isotype had no effect. The level of aggregation was dependent on anti-CD43 mAb concentration, time and temperature. Anti-leucosialin-induced aggregation of HMC-1 cells was completely inhibited by mAb against CD11a (LFA-1) and CD18 (beta 2-chain). Monoclonal antibody to CD54 (ICAM-1) partially inhibited anti-CD43-induced homotypic aggregation, while anti-CD11b (CR3), anti-CD11c (p 150, 95) and a control mAb had no inhibitory effect. We conclude that mast cell line CD43 antigen expression is differentially regulated during cell activation, and speculate that anti-CD43-induced homotypic aggregation of HMC-1 cells is closely associated with modulation of beta 2-integrins.

UI	MeSH Term	Description	Entries
D008407	Mast Cells	Granulated cells that are found in almost all tissues, most abundantly in the skin and the gastrointestinal tract. Like the BASOPHILS, mast cells contain large amounts of HISTAMINE and HEPARIN. Unlike basophils, mast cells normally remain in the tissues and do not circulate in the blood. Mast cells, derived from the bone marrow stem cells, are regulated by the STEM CELL FACTOR.	Basophils, Tissue,Basophil, Tissue,Cell, Mast,Cells, Mast,Mast Cell,Tissue Basophil,Tissue Basophils
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D002449	Cell Aggregation	The phenomenon by which dissociated cells intermixed in vitro tend to group themselves with cells of their own type.	Aggregation, Cell,Aggregations, Cell,Cell Aggregations
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000911	Antibodies, Monoclonal	Antibodies produced by a single clone of cells.	Monoclonal Antibodies,Monoclonal Antibody,Antibody, Monoclonal
D012795	Sialoglycoproteins	Glycoproteins which contain sialic acid as one of their carbohydrates. They are often found on or in the cell or tissue membranes and participate in a variety of biological activities.	Polysialoglycoprotein,Sialoglycopeptide,Sialoglycopeptides,Sialoglycoprotein,Sialoprotein,Sialoproteins,Polysialoglycoproteins
D015153	Blotting, Western	Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.	Immunoblotting, Western,Western Blotting,Western Immunoblotting,Blot, Western,Immunoblot, Western,Western Blot,Western Immunoblot,Blots, Western,Blottings, Western,Immunoblots, Western,Immunoblottings, Western,Western Blots,Western Blottings,Western Immunoblots,Western Immunoblottings
D015536	Down-Regulation	A negative regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.	Receptor Down-Regulation,Down-Regulation (Physiology),Downregulation,Down Regulation,Down-Regulation, Receptor
D015703	Antigens, CD	Differentiation antigens residing on mammalian leukocytes. CD stands for cluster of differentiation, which refers to groups of monoclonal antibodies that show similar reactivity with certain subpopulations of antigens of a particular lineage or differentiation stage. The subpopulations of antigens are also known by the same CD designation.	CD Antigen,Cluster of Differentiation Antigen,Cluster of Differentiation Marker,Differentiation Antigens, Leukocyte, Human,Leukocyte Differentiation Antigens, Human,Cluster of Differentiation Antigens,Cluster of Differentiation Markers,Antigen Cluster, Differentiation,Antigen, CD,CD Antigens,Differentiation Antigen Cluster,Differentiation Marker Cluster,Marker Cluster, Differentiation