Biomaterial Database

S-protein/vitronectin interaction with the C5b and the C8 of the complement membrane attack complex. 1996

H R Su

Department of Stomatology, Medical University of South Carolina, Charleston, USA.

S-protein/vitronectin participates in the regulation of complement-mediated lysis by incorporating into the membrane attack complex C5b-9. Subsequently, soluble SC5b-7 and SC5b-9 macromolecules are not inserted into the membrane lipid bilayer nor induce lytic pore formation. Using a dot blot binding assay, it was determined that soluble S-protein/vitronectin interacted with immobilized C5b and C8 among the five separately immobilized components (C5b, C6, C7, C8, C9) of the membrane attack complex. Those interactions imply a new model of the formation of the complement membrane attack complex and its regulation by S-protein/vitronectin.

UI	MeSH Term	Description	Entries
D003182	Complement C5	C5 plays a central role in both the classical and the alternative pathway of COMPLEMENT ACTIVATION. C5 is cleaved by C5 CONVERTASE into COMPLEMENT C5A and COMPLEMENT C5B. The smaller fragment C5a is an ANAPHYLATOXIN and mediator of inflammatory process. The major fragment C5b binds to the membrane initiating the spontaneous assembly of the late complement components, C5-C9, into the MEMBRANE ATTACK COMPLEX.	C5 Complement,Complement 5,Complement C5, Precursor,Complement Component 5,Precursor C5,Pro-C5,Pro-complement 5,C5, Complement,C5, Precursor,C5, Precursor Complement,Complement, C5,Component 5, Complement,Precursor Complement C5,Pro C5,Pro complement 5
D003185	Complement C8	A 150-kDa serum glycoprotein composed of three subunits with each encoded by a different gene (C8A; C8B; and C8G). This heterotrimer contains a disulfide-linked C8alpha-C8gamma heterodimer and a noncovalently associated C8beta chain. C8 is the next component to bind the C5-7 complex forming C5b-8 that binds COMPLEMENT C9 and acts as a catalyst in the polymerization of C9.	C8 Complement,Complement 8,Complement Component 8,Complement Component C8 alpha,Complement Component C8 alpha Chain,Complement Component C8 beta,Complement Component C8 beta Chain,Complement Component C8 gamma,Complement Component C8 gamma Chain,C8, Complement,Complement, C8,Component 8, Complement
D006493	Heparin	A highly acidic mucopolysaccharide formed of equal parts of sulfated D-glucosamine and D-glucuronic acid with sulfaminic bridges. The molecular weight ranges from six to twenty thousand. Heparin occurs in and is obtained from liver, lung, mast cells, etc., of vertebrates. Its function is unknown, but it is used to prevent blood clotting in vivo and vitro, in the form of many different salts.	Heparinic Acid,alpha-Heparin,Heparin Sodium,Liquaemin,Sodium Heparin,Unfractionated Heparin,Heparin, Sodium,Heparin, Unfractionated,alpha Heparin
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
D012995	Solubility	The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Solubilities
D015938	Complement Membrane Attack Complex	A product of COMPLEMENT ACTIVATION cascade, regardless of the pathways, that forms transmembrane channels causing disruption of the target CELL MEMBRANE and cell lysis. It is formed by the sequential assembly of terminal complement components (COMPLEMENT C5B; COMPLEMENT C6; COMPLEMENT C7; COMPLEMENT C8; and COMPLEMENT C9) into the target membrane. The resultant C5b-8-poly-C9 is the "membrane attack complex" or MAC.	Complement Complex C5b-9,Membrane Attack Complex,C 5b-9,C5b-8-poly-C9,C5b-9,Cytolytic Terminal Complement Complex,Terminal Complement Complex,C5b 8 poly C9,Complement Complex C5b 9,Complement Complex, Terminal,Complex, Terminal Complement
D050776	Complement C5b	The larger fragment generated from the cleavage of C5 by C5 CONVERTASE that yields COMPLEMENT C5A and C5b (beta chain + alpha' chain, the residual alpha chain, bound by disulfide bond). C5b remains bound to the membrane and initiates the spontaneous assembly of the late complement components to form C5b-8-poly-C9, the MEMBRANE ATTACK COMPLEX.	C5b Complement,Complement 5b,Complement Component 5b,C5b, Complement,Complement, C5b,Component 5b, Complement
D019096	Vitronectin	A blood plasma glycoprotein that mediates cell adhesion and interacts with proteins of the complement, coagulation, and fibrinolytic cascade. (From Segen, Dictionary of Modern Medicine, 1992)	Complement S Protein,Serum Spreading Factor