Biomaterial Database

Nonopsonic phagocytosis of microorganisms. 1995

I Ofek, and J Goldhar, and Y Keisari, and N Sharon

Department of Human Microbiology, Sackler Faculty of Medicine, Tel-Aviv University, Israel.

Nonopsonic phagocytosis mediated by phagocyte receptors that recognize corresponding adhesins on microbial surfaces has attracted increasing interest as a potential host defense mechanism against extracellular pathogens and as a means of survival in the host for intracellular pathogens. Three types of nonopsonic phagocytosis involving carbohydrate-protein interactions (also termed lectinophagocytosis), protein-protein interactions, and hydrophobic interactions are discussed. A prominent receptor on phagocytic cells involved in recognizing pathogens belongs to the CD11/CD18 integrins. It mediates both opsonophagocytosis and nonopsonic phagocytosis and exhibits multiple specificity for different microbial adhesins. In other cases, similar specificity toward a microbial ligand (e.g. the Klebsiella pneumoniae capsule) is shared by dual molecules, one of which (e.g. the mannose-binding protein in serum) mediates opsonophagocytosis and the other (e.g. the macrophage mannose receptor) mediates nonopsonic phagocytosis of the microorganisms. In addition, we discuss how nonopsonic phagocytosis can trigger the phagocytes to release inflammatory agents and cause tissue injury. Further studies of the molecular mechanisms of nonopsonic phagocytosis, in particular those underlying the up-regulation of the phagocytic receptors by various agents, should lead to the development of new approaches for the prevention of infectious diseases.

UI	MeSH Term	Description	Entries
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D010586	Phagocytes	Cells that can carry out the process of PHAGOCYTOSIS.	Phagocyte,Phagocytic Cell,Phagocytic Cells,Cell, Phagocytic,Cells, Phagocytic
D010587	Phagocytosis	The engulfing and degradation of microorganisms; other cells that are dead, dying, or pathogenic; and foreign particles by phagocytic cells (PHAGOCYTES).	Phagocytoses
D002240	Carbohydrate Sequence	The sequence of carbohydrates within POLYSACCHARIDES; GLYCOPROTEINS; and GLYCOLIPIDS.	Carbohydrate Sequences,Sequence, Carbohydrate,Sequences, Carbohydrate
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001419	Bacteria	One of the three domains of life (the others being Eukarya and ARCHAEA), also called Eubacteria. They are unicellular prokaryotic microorganisms which generally possess rigid cell walls, multiply by cell division, and exhibit three principal forms: round or coccal, rodlike or bacillary, and spiral or spirochetal. Bacteria can be classified by their response to OXYGEN: aerobic, anaerobic, or facultatively anaerobic; by the mode by which they obtain their energy: chemotrophy (via chemical reaction) or PHOTOTROPHY (via light reaction); for chemotrophs by their source of chemical energy: CHEMOLITHOTROPHY (from inorganic compounds) or chemoorganotrophy (from organic compounds); and by their source for CARBON; NITROGEN; etc.; HETEROTROPHY (from organic sources) or AUTOTROPHY (from CARBON DIOXIDE). They can also be classified by whether or not they stain (based on the structure of their CELL WALLS) with CRYSTAL VIOLET dye: gram-negative or gram-positive.	Eubacteria
D056890	Eukaryota	One of the three domains of life (the others being BACTERIA and ARCHAEA), also called Eukarya. These are organisms whose cells are enclosed in membranes and possess a nucleus. They comprise almost all multicellular and many unicellular organisms, and are traditionally divided into groups (sometimes called kingdoms) including ANIMALS; PLANTS; FUNGI; and various algae and other taxa that were previously part of the old kingdom Protista.	Eukaryotes,Eucarya,Eukarya,Eukaryotas,Eukaryote