Biomaterial Database

Effect of concanavalin A on intracellular killing of Staphylococcus aureus by human phagocytes. 1984

P C Leijh, and T L van Zwet, and R van Furth

This study concerns the influence of concanavalin A (Con A) on phagocytosis and intracellular killing of Staphylococcus aureus by human monocytes and granulocytes. Con A binds to S. aureus, monocytes, and granulocytes, and is not opsonic. Con A stimulates the killing of intracellular serum opsonized S. aureus by monocytes, but not by granulocytes. This stimulation of intracellular killing was inhibited by alpha-methyl-mannoside, indicating that the process occurs via Con A specific membrane binding sites. Unlike (tetravalent) Con A, divalent succinyl-Con A does not stimulate intracellular killing, indicating that the lectin valency is important for this stimulation. Con A bound to Sephadex particles, that can not be ingested by monocytes, does not stimulate intracellular killing of S. aureus either, although it, like free Con A, stimulates H2O2 production. Pre-incubation of monocytes with Con A inhibited Fc gamma and C3b-mediated ingestion of S. aureus as well as stimulation of the killing by serum. Divalent Con A had no effect on these functions. This inhibition by Con A is in all probability due to a steric impedance of Con A with respect to the interaction of IgG and C3b with their membrane receptors. Fluorescence techniques showed that Con A was localized on the membrane and in the cytoplasm of the monocytes, whereas granulocytes had only membrane bound lectin. Taken together, these findings suggest that cell penetration by the lectin is obligatory for the stimulation of intracellular killing.

UI	MeSH Term	Description	Entries
D008766	Methylmannosides	Mannosides formed by the reaction of the hydroxyl group on the anomeric carbon atom of mannose with methyl alcohol. They include both alpha- and beta-methylmannosides.	Methylmannopyranosides
D009000	Monocytes	Large, phagocytic mononuclear leukocytes produced in the vertebrate BONE MARROW and released into the BLOOD; contain a large, oval or somewhat indented nucleus surrounded by voluminous cytoplasm and numerous organelles.	Monocyte
D010587	Phagocytosis	The engulfing and degradation of microorganisms; other cells that are dead, dying, or pathogenic; and foreign particles by phagocytic cells (PHAGOCYTES).	Phagocytoses
D011952	Receptors, Concanavalin A	Glycoprotein moieties on the surfaces of cell membranes that bind concanavalin A selectively; the number and location of the sites depends on the type and condition of the cell.	Concanavalin A Binding Sites,Concanavalin A Receptors,Concanavalin A Receptor,Receptor, Concanavalin A
D011961	Receptors, Fc	Molecules found on the surface of some, but not all, B-lymphocytes, T-lymphocytes, and macrophages, which recognize and combine with the Fc (crystallizable) portion of immunoglobulin molecules.	Fc Receptors,Fc Receptor,Receptor, Fc
D001770	Blood Bactericidal Activity	The natural bactericidal property of BLOOD due to normally occurring antibacterial substances such as beta lysin, leukin, etc. This activity needs to be distinguished from the bactericidal activity contained in a patient's serum as a result of antimicrobial therapy, which is measured by a SERUM BACTERICIDAL TEST.	Activities, Blood Bactericidal,Activity, Blood Bactericidal,Bactericidal Activities, Blood,Bactericidal Activity, Blood,Blood Bactericidal Activities
D003179	Complement C3b	The larger fragment generated from the cleavage of COMPLEMENT C3 by C3 CONVERTASE. It is a constituent of the ALTERNATIVE PATHWAY C3 CONVERTASE (C3bBb), and COMPLEMENT C5 CONVERTASES in both the classical (C4b2a3b) and the alternative (C3bBb3b) pathway. C3b participates in IMMUNE ADHERENCE REACTION and enhances PHAGOCYTOSIS. It can be inactivated (iC3b) or cleaved by various proteases to yield fragments such as COMPLEMENT C3C; COMPLEMENT C3D; C3e; C3f; and C3g.	C3b Complement,C3bi,Complement 3b,Complement Component 3b,Inactivated C3b,iC3b,C3b, Complement,C3b, Inactivated,Complement, C3b,Component 3b, Complement
D003208	Concanavalin A	A MANNOSE/GLUCOSE binding lectin isolated from the jack bean (Canavalia ensiformis). It is a potent mitogen used to stimulate cell proliferation in lymphocytes, primarily T-lymphocyte, cultures.
D006098	Granulocytes	Leukocytes with abundant granules in the cytoplasm. They are divided into three groups according to the staining properties of the granules: neutrophilic, eosinophilic, and basophilic. Mature granulocytes are the NEUTROPHILS; EOSINOPHILS; and BASOPHILS.	Granulocyte
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man