Complement C3: A glycoprotein that is central in both the classical and the alternative pathway of COMPLEMENT ACTIVATION. C3 can be cleaved into COMPLEMENT C3A and COMPLEMENT C3B, spontaneously at low level or by C3 CONVERTASE at high level. The smaller fragment C3a is an ANAPHYLATOXIN and mediator of local inflammatory process. The larger fragment C3b binds with C3 convertase to form C5 convertase.Complement C4: A glycoprotein that is important in the activation of CLASSICAL COMPLEMENT PATHWAY. C4 is cleaved by the activated COMPLEMENT C1S into COMPLEMENT C4A and COMPLEMENT C4B.Complement Activation: The sequential activation of serum COMPLEMENT PROTEINS to create the COMPLEMENT MEMBRANE ATTACK COMPLEX. Factors initiating complement activation include ANTIGEN-ANTIBODY COMPLEXES, microbial ANTIGENS, or cell surface POLYSACCHARIDES.Complement System Proteins: Serum glycoproteins participating in the host defense mechanism of COMPLEMENT ACTIVATION that creates the COMPLEMENT MEMBRANE ATTACK COMPLEX. Included are glycoproteins in the various pathways of complement activation (CLASSICAL COMPLEMENT PATHWAY; ALTERNATIVE COMPLEMENT PATHWAY; and LECTIN COMPLEMENT PATHWAY).Complement C4a: The smaller fragment formed when complement C4 is cleaved by COMPLEMENT C1S. It is an anaphylatoxin that causes symptoms of immediate hypersensitivity (HYPERSENSITIVITY, IMMEDIATE) but its activity is weaker than that of COMPLEMENT C3A or COMPLEMENT C5A.Complement C1q: A subcomponent of complement C1, composed of six copies of three polypeptide chains (A, B, and C), each encoded by a separate gene (C1QA; C1QB; C1QC). This complex is arranged in nine subunits (six disulfide-linked dimers of A and B, and three disulfide-linked homodimers of C). C1q has binding sites for antibodies (the heavy chain of IMMUNOGLOBULIN G or IMMUNOGLOBULIN M). The interaction of C1q and immunoglobulin activates the two proenzymes COMPLEMENT C1R and COMPLEMENT C1S, thus initiating the cascade of COMPLEMENT ACTIVATION via the CLASSICAL COMPLEMENT PATHWAY.Complement C3a: The smaller fragment generated from the cleavage of complement C3 by C3 CONVERTASE. C3a, a 77-amino acid peptide, is a mediator of local inflammatory process. It induces smooth MUSCLE CONTRACTION, and HISTAMINE RELEASE from MAST CELLS and LEUKOCYTES. C3a is considered an anaphylatoxin along with COMPLEMENT C4A; COMPLEMENT C5A; and COMPLEMENT C5A, DES-ARGININE.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.Complement C5a: The minor fragment formed when C5 convertase cleaves C5 into C5a and COMPLEMENT C5B. C5a is a 74-amino-acid glycopeptide with a carboxy-terminal ARGININE that is crucial for its spasmogenic activity. Of all the complement-derived anaphylatoxins, C5a is the most potent in mediating immediate hypersensitivity (HYPERSENSITIVITY, IMMEDIATE), smooth MUSCLE CONTRACTION; HISTAMINE RELEASE; and migration of LEUKOCYTES to site of INFLAMMATION.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.Complement C4b: The large fragment formed when COMPLEMENT C4 is cleaved by COMPLEMENT C1S. The membrane-bound C4b binds COMPLEMENT C2A, a SERINE PROTEASE, to form C4b2a (CLASSICAL PATHWAY C3 CONVERTASE) and subsequent C4b2a3b (CLASSICAL PATHWAY C5 CONVERTASE).Complement C6: A 105-kDa serum glycoprotein with significant homology to the other late complement components, C7-C9. It is a polypeptide chain cross-linked by 32 disulfide bonds. C6 is the next complement component to bind to the membrane-bound COMPLEMENT C5B in the assembly of MEMBRANE ATTACK COMPLEX. It is encoded by gene C6.Complement C9: A 63-kDa serum glycoprotein encoded by gene C9. Monomeric C9 (mC9) binds the C5b-8 complex to form C5b-9 which catalyzes the polymerization of C9 forming C5b-p9 (MEMBRANE ATTACK COMPLEX) and transmembrane channels leading to lysis of the target cell. Patients with C9 deficiency suffer from recurrent bacterial infections.Complement C2: A component of the CLASSICAL COMPLEMENT PATHWAY. C2 is cleaved by activated COMPLEMENT C1S into COMPLEMENT C2B and COMPLEMENT C2A. C2a, the COOH-terminal fragment containing a SERINE PROTEASE, combines with COMPLEMENT C4B to form C4b2a (CLASSICAL PATHWAY C3 CONVERTASE) and subsequent C4b2a3b (CLASSICAL PATHWAY C5 CONVERTASE).Receptors, Complement: Molecules on the surface of some B-lymphocytes and macrophages, that recognize and combine with the C3b, C3d, C1q, and C4b components of complement.Complement C3d: A 302-amino-acid fragment in the alpha chain (672-1663) of C3b. It is generated when C3b is inactivated (iC3b) and its alpha chain is cleaved by COMPLEMENT FACTOR I into C3c, and C3dg (955-1303) in the presence COMPLEMENT FACTOR H. Serum proteases further degrade C3dg into C3d (1002-1303) and C3g (955-1001).Complement C3c: A 206-amino-acid fragment in the alpha chain (672-1663) of C3b. It is generated when C3b is inactivated (iC3b) and its alpha chain is cleaved by COMPLEMENT FACTOR I into C3c (749-954), and C3dg (955-1303) in the presence COMPLEMENT FACTOR H.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 Inactivator Proteins: Serum proteins that negatively regulate the cascade process of COMPLEMENT ACTIVATION. Uncontrolled complement activation and resulting cell lysis is potentially dangerous for the host. The complement system is tightly regulated by inactivators that accelerate the decay of intermediates and certain cell surface receptors.Complement Pathway, Alternative: Complement activation initiated by the interaction of microbial ANTIGENS with COMPLEMENT C3B. When COMPLEMENT FACTOR B binds to the membrane-bound C3b, COMPLEMENT FACTOR D cleaves it to form alternative C3 CONVERTASE (C3BBB) which, stabilized by COMPLEMENT FACTOR P, is able to cleave multiple COMPLEMENT C3 to form alternative C5 CONVERTASE (C3BBB3B) leading to cleavage of COMPLEMENT C5 and the assembly of COMPLEMENT MEMBRANE ATTACK COMPLEX.Complement Pathway, Classical: Complement activation initiated by the binding of COMPLEMENT C1 to ANTIGEN-ANTIBODY COMPLEXES at the COMPLEMENT C1Q subunit. This leads to the sequential activation of COMPLEMENT C1R and COMPLEMENT C1S subunits. Activated C1s cleaves COMPLEMENT C4 and COMPLEMENT C2 forming the membrane-bound classical C3 CONVERTASE (C4B2A) and the subsequent C5 CONVERTASE (C4B2A3B) leading to cleavage of COMPLEMENT C5 and the assembly of COMPLEMENT MEMBRANE ATTACK COMPLEX.Complement C1s: A 77-kDa subcomponent of complement C1, encoded by gene C1S, is a SERINE PROTEASE existing as a proenzyme (homodimer) in the intact complement C1 complex. Upon the binding of COMPLEMENT C1Q to antibodies, the activated COMPLEMENT C1R cleaves C1s into two chains, A (heavy) and B (light, the serine protease), linked by disulfide bonds yielding the active C1s. The activated C1s, in turn, cleaves COMPLEMENT C2 and COMPLEMENT C4 to form C4b2a (CLASSICAL C3 CONVERTASE).Complement Factor B: A glycine-rich, heat-labile serum glycoprotein that contains a component of the C3 CONVERTASE ALTERNATE PATHWAY (C3bBb). Bb, a serine protease, is generated when factor B is cleaved by COMPLEMENT FACTOR D into Ba and Bb.Complement C7: A 93-kDa serum glycoprotein encoded by C7 gene. It is a polypeptide chain with 28 disulfide bridges. In the formation of MEMBRANE ATTACK COMPLEX; C7 is the next component to bind the C5b-6 complex forming a trimolecular complex C5b-7 which is lipophilic, resembles an integral membrane protein, and serves as an anchor for the late complement components, C8 and C9.Complement C3-C5 Convertases: Serine proteases that cleave COMPLEMENT C3 into COMPLEMENT C3A and COMPLEMENT C3B, or cleave COMPLEMENT C5 into COMPLEMENT C5A and COMPLEMENT C5B. These include the different forms of C3/C5 convertases in the classical and the alternative pathways of COMPLEMENT ACTIVATION. Both cleavages take place at the C-terminal of an ARGININE residue.Complement C1: The first complement component to act in the activation of CLASSICAL COMPLEMENT PATHWAY. It is a calcium-dependent trimolecular complex made up of three subcomponents: COMPLEMENT C1Q; COMPLEMENT C1R; and COMPLEMENT C1S at 1:2:2 ratios. When the intact C1 binds to at least two antibodies (involving C1q), C1r and C1s are sequentially activated, leading to subsequent steps in the cascade of COMPLEMENT ACTIVATION.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.Complement C1r: A 80-kDa subcomponent of complement C1, existing as a SERINE PROTEASE proenzyme in the intact complement C1 complex. When COMPLEMENT C1Q is bound to antibodies, the changed tertiary structure causes autolytic activation of complement C1r which is cleaved into two chains, A (heavy) and B (light, the serine protease), connected by disulfide bonds. The activated C1r serine protease, in turn, activates COMPLEMENT C1S proenzyme by cleaving the Arg426-Ile427 bond. No fragment is released when either C1r or C1s is cleaved.Complement Factor H: An important soluble regulator of the alternative pathway of complement activation (COMPLEMENT ACTIVATION PATHWAY, ALTERNATIVE). It is a 139-kDa glycoprotein expressed by the liver and secreted into the blood. It binds to COMPLEMENT C3B and makes iC3b (inactivated complement 3b) susceptible to cleavage by COMPLEMENT FACTOR I. Complement factor H also inhibits the association of C3b with COMPLEMENT FACTOR B to form the C3bB proenzyme, and promotes the dissociation of Bb from the C3bBb complex (COMPLEMENT C3 CONVERTASE, ALTERNATIVE PATHWAY).Receptors, Complement 3b: Molecular sites on or in some B-lymphocytes and macrophages that recognize and combine with COMPLEMENT C3B. The primary structure of these receptors reveal that they contain transmembrane and cytoplasmic domains, with their extracellular portion composed entirely of thirty short consensus repeats each having 60 to 70 amino acids.Complement Inactivating Agents: Compounds that negatively regulate the cascade process of COMPLEMENT ACTIVATION. Uncontrolled complement activation and resulting cell lysis is potentially dangerous for the host.Complement Activating Enzymes: Enzymes that activate one or more COMPLEMENT PROTEINS in the complement system leading to the formation of the COMPLEMENT MEMBRANE ATTACK COMPLEX, an important response in host defense. They are enzymes in the various COMPLEMENT ACTIVATION pathways.Complement Hemolytic Activity Assay: A screening assay for circulating COMPLEMENT PROTEINS. Diluted SERUM samples are added to antibody-coated ERYTHROCYTES and the percentage of cell lysis is measured. The values are expressed by the so called CH50, in HEMOLYTIC COMPLEMENT units per milliliter, which is the dilution of serum required to lyse 50 percent of the erythrocytes in the assay.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.Receptors, Complement 3d: Molecular sites on or in B-lymphocytes, follicular dendritic cells, lymphoid cells, and epithelial cells that recognize and combine with COMPLEMENT C3D. Human complement receptor 2 (CR2) serves as a receptor for both C3dg and the gp350/220 glycoprotein of HERPESVIRUS 4, HUMAN, and binds the monoclonal antibody OKB7, which blocks binding of both ligands to the receptor.Complement Fixation Tests: Serologic tests based on inactivation of complement by the antigen-antibody complex (stage 1). Binding of free complement can be visualized by addition of a second antigen-antibody system such as red cells and appropriate red cell antibody (hemolysin) requiring complement for its completion (stage 2). Failure of the red cells to lyse indicates that a specific antigen-antibody reaction has taken place in stage 1. If red cells lyse, free complement is present indicating no antigen-antibody reaction occurred in stage 1.Receptor, Anaphylatoxin C5a: A G-protein-coupled receptor that signals an increase in intracellular calcium in response to the potent ANAPHYLATOXIN peptide COMPLEMENT C5A.Bacteriolysis: Rupture of bacterial cells due to mechanical force, chemical action, or the lytic growth of BACTERIOPHAGES.Complement C1 Inactivator Proteins: Serum proteins that inhibit, antagonize, or inactivate COMPLEMENT C1 or its subunits.Complement Factor D: A serum protein which is important in the ALTERNATIVE COMPLEMENT ACTIVATION PATHWAY. This enzyme cleaves the COMPLEMENT C3B-bound COMPLEMENT FACTOR B to form C3bBb which is ALTERNATIVE PATHWAY C3 CONVERTASE.Complement C2a: The COOH-terminal fragment of COMPLEMENT 2, released by the action of activated COMPLEMENT C1S. It is a SERINE PROTEASE. C2a combines with COMPLEMENT C4B to form C4b2a (CLASSICAL PATHWAY C3 CONVERTASE) and subsequent C4b2a3b (CLASSICAL PATHWAY C5 CONVERTASE).Anaphylatoxins: Serum peptides derived from certain cleaved COMPLEMENT PROTEINS during COMPLEMENT ACTIVATION. They induce smooth MUSCLE CONTRACTION; mast cell HISTAMINE RELEASE; PLATELET AGGREGATION; and act as mediators of the local inflammatory process. The order of anaphylatoxin activity from the strongest to the weakest is C5a, C3a, C4a, and C5a des-arginine.Complement Factor I: A plasma serine proteinase that cleaves the alpha-chains of C3b and C4b in the presence of the cofactors COMPLEMENT FACTOR H and C4-binding protein, respectively. It is a 66-kDa glycoprotein that converts C3b to inactivated C3b (iC3b) followed by the release of two fragments, C3c (150-kDa) and C3dg (41-kDa). It was formerly called KAF, C3bINF, or enzyme 3b inactivator.Hemolysis: The destruction of ERYTHROCYTES by many different causal agents such as antibodies, bacteria, chemicals, temperature, and changes in tonicity.Complement C3b Inactivator Proteins: Endogenous proteins that inhibit or inactivate COMPLEMENT C3B. They include COMPLEMENT FACTOR H and COMPLEMENT FACTOR I (C3b/C4b inactivator). They cleave or promote the cleavage of C3b into inactive fragments, and thus are important in the down-regulation of COMPLEMENT ACTIVATION and its cytolytic sequence.Antigens, CD55: GPI-linked membrane proteins broadly distributed among hematopoietic and non-hematopoietic cells. CD55 prevents the assembly of C3 CONVERTASE or accelerates the disassembly of preformed convertase, thus blocking the formation of the membrane attack complex.Antigens, CD59: Small glycoproteins found on both hematopoietic and non-hematopoietic cells. CD59 restricts the cytolytic activity of homologous complement by binding to C8 and C9 and blocking the assembly of the membrane attack complex. (From Barclay et al., The Leukocyte Antigen FactsBook, 1993, p234)Complement C4b-Binding Protein: A serum protein that regulates the CLASSICAL COMPLEMENT ACTIVATION PATHWAY. It binds as a cofactor to COMPLEMENT FACTOR I which then hydrolyzes the COMPLEMENT C4B in the CLASSICAL PATHWAY C3 CONVERTASE (C4bC2a).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.Cobra Venoms: Venoms from snakes of the genus Naja (family Elapidae). They contain many specific proteins that have cytotoxic, hemolytic, neurotoxic, and other properties. Like other elapid venoms, they are rich in enzymes. They include cobramines and cobralysins.Cytotoxicity, Immunologic: The phenomenon of target cell destruction by immunologically active effector cells. It may be brought about directly by sensitized T-lymphocytes or by lymphoid or myeloid "killer" cells, or it may be mediated by cytotoxic antibody, cytotoxic factor released by lymphoid cells, or complement.Complement C1 Inhibitor Protein: An endogenous 105-kDa plasma glycoprotein produced primarily by the LIVER and MONOCYTES. It inhibits a broad spectrum of proteases, including the COMPLEMENT C1R and the COMPLEMENT C1S proteases of the CLASSICAL COMPLEMENT PATHWAY, and the MANNOSE-BINDING PROTEIN-ASSOCIATED SERINE PROTEASES. C1-INH-deficient individuals suffer from HEREDITARY ANGIOEDEMA TYPES I AND II.Antigen-Antibody Complex: The complex formed by the binding of antigen and antibody molecules. The deposition of large antigen-antibody complexes leading to tissue damage causes IMMUNE COMPLEX DISEASES.Complement C3 Convertase, Alternative Pathway: A serine protease that is the complex of COMPLEMENT C3B and COMPLEMENT FACTOR BB. It cleaves multiple COMPLEMENT C3 into COMPLEMENT C3A (anaphylatoxin) and COMPLEMENT C3B in the ALTERNATIVE COMPLEMENT ACTIVATION PATHWAY.Immunoglobulin G: The major immunoglobulin isotype class in normal human serum. There are several isotype subclasses of IgG, for example, IgG1, IgG2A, and IgG2B.Antigens, CD46: A ubiquitously expressed complement receptor that binds COMPLEMENT C3B and COMPLEMENT C4B and serves as a cofactor for their inactivation. CD46 also interacts with a wide variety of pathogens and mediates immune response.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.Complement C2b: The N-terminal fragment of COMPLEMENT 2, released by the action of activated COMPLEMENT C1S.Complement Pathway, Mannose-Binding Lectin: Complement activation triggered by the interaction of microbial POLYSACCHARIDES with serum MANNOSE-BINDING LECTIN resulting in the activation of MANNOSE-BINDING PROTEIN-ASSOCIATED SERINE PROTEASES. As in the classical pathway, MASPs cleave COMPLEMENT C4 and COMPLEMENT C2 to form C3 CONVERTASE (C4B2A) and the subsequent C5 CONVERTASE (C4B2A3B) leading to cleavage of COMPLEMENT C5 and assembly of COMPLEMENT MEMBRANE ATTACK COMPLEX.Properdin: A 53-kDa protein that is a positive regulator of the alternate pathway of complement activation (COMPLEMENT ACTIVATION PATHWAY, ALTERNATIVE). It stabilizes the ALTERNATIVE PATHWAY C3 CONVERTASE (C3bBb) and protects it from rapid inactivation, thus facilitating the cascade of COMPLEMENT ACTIVATION and the formation of MEMBRANE ATTACK COMPLEX. Individuals with mutation in the PFC gene exhibit properdin deficiency and have a high susceptibility to infections.Opsonin Proteins: Proteins that bind to particles and cells to increase susceptibility to PHAGOCYTOSIS, especially ANTIBODIES bound to EPITOPES that attach to FC RECEPTORS. COMPLEMENT C3B may also participate.Phagocytosis: The engulfing and degradation of microorganisms; other cells that are dead, dying, or pathogenic; and foreign particles by phagocytic cells (PHAGOCYTES).Complement C3-C5 Convertases, Classical Pathway: Important enzymes in the CLASSICAL COMPLEMENT ACTIVATION PATHWAY. They cleave COMPLEMENT C3 and COMPLEMENT C5.Genetic Complementation Test: A test used to determine whether or not complementation (compensation in the form of dominance) will occur in a cell with a given mutant phenotype when another mutant genome, encoding the same mutant phenotype, is introduced into that cell.Erythrocytes: Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.Antibodies, Monoclonal: Antibodies produced by a single clone of cells.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Antibody-Dependent Cell Cytotoxicity: The phenomenon of antibody-mediated target cell destruction by non-sensitized effector cells. The identity of the target cell varies, but it must possess surface IMMUNOGLOBULIN G whose Fc portion is intact. The effector cell is a "killer" cell possessing Fc receptors. It may be a lymphocyte lacking conventional B- or T-cell markers, or a monocyte, macrophage, or polynuclear leukocyte, depending on the identity of the target cell. The reaction is complement-independent.Protein Binding: The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Neutrophils: Granular leukocytes having a nucleus with three to five lobes connected by slender threads of chromatin, and cytoplasm containing fine inconspicuous granules and stainable by neutral dyes.Mice, Inbred C57BLSteroid 21-Hydroxylase: An adrenal microsomal cytochrome P450 enzyme that catalyzes the 21-hydroxylation of steroids in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP21 gene, converts progesterones to precursors of adrenal steroid hormones (CORTICOSTERONE; HYDROCORTISONE). Defects in CYP21 cause congenital adrenal hyperplasia (ADRENAL HYPERPLASIA, CONGENITAL).Blood Proteins: Proteins that are present in blood serum, including SERUM ALBUMIN; BLOOD COAGULATION FACTORS; and many other types of proteins.Bacterial Proteins: Proteins found in any species of bacterium.Complement C3 Convertase, Classical Pathway: A serine protease that cleaves multiple COMPLEMENT 3 into COMPLEMENT 3A (anaphylatoxin) and COMPLEMENT 3B in the CLASSICAL COMPLEMENT ACTIVATION PATHWAY. It is a complex of COMPLEMENT 4B and COMPLEMENT 2A (C4b2a).Cells, Cultured: Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.Complement C3-C5 Convertases, Alternative Pathway: Important enzymes in the ALTERNATIVE COMPLEMENT ACTIVATION PATHWAY. They cleave COMPLEMENT C3 and COMPLEMENT C5.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Lupus Erythematosus, Systemic: A chronic, relapsing, inflammatory, and often febrile multisystemic disorder of connective tissue, characterized principally by involvement of the skin, joints, kidneys, and serosal membranes. It is of unknown etiology, but is thought to represent a failure of the regulatory mechanisms of the autoimmune system. The disease is marked by a wide range of system dysfunctions, an elevated erythrocyte sedimentation rate, and the formation of LE cells in the blood or bone marrow.Complement C5a, des-Arginine: A derivative of complement C5a, generated when the carboxy-terminal ARGININE is removed by CARBOXYPEPTIDASE B present in normal human serum. C5a des-Arg shows complete loss of spasmogenic activity though it retains some chemotactic ability (CHEMOATTRACTANTS).Macrophage-1 Antigen: An adhesion-promoting leukocyte surface membrane heterodimer. The alpha subunit consists of the CD11b ANTIGEN and the beta subunit the CD18 ANTIGEN. The antigen, which is an integrin, functions both as a receptor for complement 3 and in cell-cell and cell-substrate adhesive interactions.Complement C5 Convertase, Classical Pathway: A serine protease that cleaves multiple COMPLEMENT 5 into COMPLEMENT 5A (anaphylatoxin) and COMPLEMENT 5B in the CLASSICAL COMPLEMENT ACTIVATION PATHWAY. It is a complex of CLASSICAL PATHWAY C3 CONVERTASE (C4b2a) with an additional COMPLEMENT C3B, or C4b2a3b.Escherichia coli: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.Cytotoxicity Tests, Immunologic: The demonstration of the cytotoxic effect on a target cell of a lymphocyte, a mediator released by a sensitized lymphocyte, an antibody, or complement.Killer Cells, Natural: Bone marrow-derived lymphocytes that possess cytotoxic properties, classically directed against transformed and virus-infected cells. Unlike T CELLS; and B CELLS; NK CELLS are not antigen specific. The cytotoxicity of natural killer cells is determined by the collective signaling of an array of inhibitory and stimulatory CELL SURFACE RECEPTORS. A subset of T-LYMPHOCYTES referred to as NATURAL KILLER T CELLS shares some of the properties of this cell type.Immunoglobulin M: A class of immunoglobulin bearing mu chains (IMMUNOGLOBULIN MU-CHAINS). IgM can fix COMPLEMENT. The name comes from its high molecular weight and originally being called a macroglobulin.Complement C5 Convertase, Alternative Pathway: A serine protease that cleaves multiple COMPLEMENT C5 into COMPLEMENT C5A (anaphylatoxin) and COMPLEMENT C5B in the ALTERNATIVE COMPLEMENT ACTIVATION PATHWAY. It is the complex of ALTERNATIVE PATHWAY C3 CONVERTASE (C3bBb) with an additional COMPLEMENT C3B, or C3bBb3b.Rabbits: The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.Antibodies: Immunoglobulin molecules having a specific amino acid sequence by virtue of which they interact only with the ANTIGEN (or a very similar shape) that induced their synthesis in cells of the lymphoid series (especially PLASMA CELLS).Recombinant Proteins: Proteins prepared by recombinant DNA technology.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.Enzyme-Linked Immunosorbent Assay: An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed.Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.Macrophages: The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood MONOCYTES. Main types are PERITONEAL MACROPHAGES; ALVEOLAR MACROPHAGES; HISTIOCYTES; KUPFFER CELLS of the liver; and OSTEOCLASTS. They may further differentiate within chronic inflammatory lesions to EPITHELIOID CELLS or may fuse to form FOREIGN BODY GIANT CELLS or LANGHANS GIANT CELLS. (from The Dictionary of Cell Biology, Lackie and Dow, 3rd ed.)Mannose-Binding Lectin: A specific mannose-binding member of the collectin family of lectins. It binds to carbohydrate groups on invading pathogens and plays a key role in the MANNOSE-BINDING LECTIN COMPLEMENT PATHWAY.Mice, Inbred BALB CAntigens, 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.Membrane Glycoproteins: Glycoproteins found on the membrane or surface of cells.Mice, Knockout: Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.Tumor Lysis Syndrome: A syndrome resulting from cytotoxic therapy, occurring generally in aggressive, rapidly proliferating lymphoproliferative disorders. It is characterized by combinations of hyperuricemia, lactic acidosis, hyperkalemia, hyperphosphatemia and hypocalcemia.Kinetics: The rate dynamics in chemical or physical systems.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Serum: The clear portion of BLOOD that is left after BLOOD COAGULATION to remove BLOOD CELLS and clotting proteins.Immunity, Innate: The capacity of a normal organism to remain unaffected by microorganisms and their toxins. It results from the presence of naturally occurring ANTI-INFECTIVE AGENTS, constitutional factors such as BODY TEMPERATURE and immediate acting immune cells such as NATURAL KILLER CELLS.Kidney Glomerulus: A cluster of convoluted capillaries beginning at each nephric tubule in the kidney and held together by connective tissue.Glomerulonephritis: Inflammation of the renal glomeruli (KIDNEY GLOMERULUS) that can be classified by the type of glomerular injuries including antibody deposition, complement activation, cellular proliferation, and glomerulosclerosis. These structural and functional abnormalities usually lead to HEMATURIA; PROTEINURIA; HYPERTENSION; and RENAL INSUFFICIENCY.RNA, Messenger: RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.Glycoproteins: Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.Glomerulonephritis, Membranoproliferative: Chronic glomerulonephritis characterized histologically by proliferation of MESANGIAL CELLS, increase in the MESANGIAL EXTRACELLULAR MATRIX, and a thickening of the glomerular capillary walls. This may appear as a primary disorder or secondary to other diseases including infections and autoimmune disease SYSTEMIC LUPUS ERYTHEMATOSUS. Various subtypes are classified by their abnormal ultrastructures and immune deposits. Hypocomplementemia is a characteristic feature of all types of MPGN.Peptide Fragments: Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.N-Acetylmuramoyl-L-alanine Amidase: An autolytic enzyme bound to the surface of bacterial cell walls. It catalyzes the hydrolysis of the link between N-acetylmuramoyl residues and L-amino acid residues in certain cell wall glycopeptides, particularly peptidoglycan. EC 3.5.1.28.Membrane Proteins: Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.Flow Cytometry: Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Major Histocompatibility Complex: The genetic region which contains the loci of genes which determine the structure of the serologically defined (SD) and lymphocyte-defined (LD) TRANSPLANTATION ANTIGENS, genes which control the structure of the IMMUNE RESPONSE-ASSOCIATED ANTIGENS, HUMAN; the IMMUNE RESPONSE GENES which control the ability of an animal to respond immunologically to antigenic stimuli, and genes which determine the structure and/or level of the first four components of complement.Disease Models, Animal: Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.ZymosanSpecies Specificity: The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Mannose-Binding Protein-Associated Serine Proteases: Serum serine proteases which participate in COMPLEMENT ACTIVATION. They are activated when complexed with the MANNOSE-BINDING LECTIN, therefore also known as Mannose-binding protein-Associated Serine Proteases (MASPs). They cleave COMPLEMENT C4 and COMPLEMENT C2 to form C4b2a, the CLASSICAL PATHWAY C3 CONVERTASE.Autoantibodies: Antibodies that react with self-antigens (AUTOANTIGENS) of the organism that produced them.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.DNA: A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).Polymerase Chain Reaction: In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.Molecular Weight: The sum of the weight of all the atoms in a molecule.Carrier Proteins: Transport proteins that carry specific substances in the blood or across cell membranes.Immunoglobulins: Multi-subunit proteins which function in IMMUNITY. They are produced by B LYMPHOCYTES from the IMMUNOGLOBULIN GENES. They are comprised of two heavy (IMMUNOGLOBULIN HEAVY CHAINS) and two light chains (IMMUNOGLOBULIN LIGHT CHAINS) with additional ancillary polypeptide chains depending on their isoforms. The variety of isoforms include monomeric or polymeric forms, and transmembrane forms (B-CELL ANTIGEN RECEPTORS) or secreted forms (ANTIBODIES). They are divided by the amino acid sequence of their heavy chains into five classes (IMMUNOGLOBULIN A; IMMUNOGLOBULIN D; IMMUNOGLOBULIN E; IMMUNOGLOBULIN G; IMMUNOGLOBULIN M) and various subclasses.Schistosoma: A genus of trematode flukes belonging to the family Schistosomatidae. There are over a dozen species. These parasites are found in man and other mammals. Snails are the intermediate hosts.T-Lymphocytes: Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES, CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES, HELPER-INDUCER). They are formed when lymphocytes circulate through the THYMUS GLAND and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen.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.T-Lymphocytes, Cytotoxic: Immunized T-lymphocytes which can directly destroy appropriate target cells. These cytotoxic lymphocytes may be generated in vitro in mixed lymphocyte cultures (MLC), in vivo during a graft-versus-host (GVH) reaction, or after immunization with an allograft, tumor cell or virally transformed or chemically modified target cell. The lytic phenomenon is sometimes referred to as cell-mediated lympholysis (CML). These CD8-positive cells are distinct from NATURAL KILLER CELLS and NATURAL KILLER T-CELLS. There are two effector phenotypes: TC1 and TC2.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.Protein Structure, Tertiary: The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.Microscopy, Electron: Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.Cell Wall: The outermost layer of a cell in most PLANTS; BACTERIA; FUNGI; and ALGAE. The cell wall is usually a rigid structure that lies external to the CELL MEMBRANE, and provides a protective barrier against physical or chemical agents.Fluorescent Antibody Technique: Test for tissue antigen using either a direct method, by conjugation of antibody with fluorescent dye (FLUORESCENT ANTIBODY TECHNIQUE, DIRECT) or an indirect method, by formation of antigen-antibody complex which is then labeled with fluorescein-conjugated anti-immunoglobulin antibody (FLUORESCENT ANTIBODY TECHNIQUE, INDIRECT). The tissue is then examined by fluorescence microscopy.HLA Antigens: Antigens determined by leukocyte loci found on chromosome 6, the major histocompatibility loci in humans. They are polypeptides or glycoproteins found on most nucleated cells and platelets, determine tissue types for transplantation, and are associated with certain diseases.Antigens, Surface: Antigens on surfaces of cells, including infectious or foreign cells or viruses. They are usually protein-containing groups on cell membranes or walls and may be isolated.Dose-Response Relationship, Immunologic: A specific immune response elicited by a specific dose of an immunologically active substance or cell in an organism, tissue, or cell.Gene Expression Regulation: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.Alleles: Variant forms of the same gene, occupying the same locus on homologous CHROMOSOMES, and governing the variants in production of the same gene product.Arteriolosclerosis: Thickening of the walls of small ARTERIES or ARTERIOLES due to cell proliferation or HYALINE deposition.Collectins: A class of C-type lectins that target the carbohydrate structures found on invading pathogens. Binding of collectins to microorganisms results in their agglutination and enhanced clearance. Collectins form trimers that may assemble into larger oligomers. Each collectin polypeptide chain consists of four regions: a relatively short N-terminal region, a collagen-like region, an alpha-helical coiled-coil region, and carbohydrate-binding region.Surface Plasmon Resonance: A biosensing technique in which biomolecules capable of binding to specific analytes or ligands are first immobilized on one side of a metallic film. Light is then focused on the opposite side of the film to excite the surface plasmons, that is, the oscillations of free electrons propagating along the film's surface. The refractive index of light reflecting off this surface is measured. When the immobilized biomolecules are bound by their ligands, an alteration in surface plasmons on the opposite side of the film is created which is directly proportional to the change in bound, or adsorbed, mass. Binding is measured by changes in the refractive index. The technique is used to study biomolecular interactions, such as antigen-antibody binding.Hemoglobinuria, Paroxysmal: A condition characterized by the recurrence of HEMOGLOBINURIA caused by intravascular HEMOLYSIS. In cases occurring upon cold exposure (paroxysmal cold hemoglobinuria), usually after infections, there is a circulating antibody which is also a cold hemolysin. In cases occurring during or after sleep (paroxysmal nocturnal hemoglobinuria), the clonal hematopoietic stem cells exhibit a global deficiency of cell membrane proteins.Serine Endopeptidases: Any member of the group of ENDOPEPTIDASES containing at the active site a serine residue involved in catalysis.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.Pore Forming Cytotoxic Proteins: Proteins secreted from an organism which form membrane-spanning pores in target cells to destroy them. This is in contrast to PORINS and MEMBRANE TRANSPORT PROTEINS that function within the synthesizing organism and COMPLEMENT immune proteins. These pore forming cytotoxic proteins are a form of primitive cellular defense which are also found in human LYMPHOCYTES.Plasmids: Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.B-Lymphocytes: Lymphoid cells concerned with humoral immunity. They are short-lived cells resembling bursa-derived lymphocytes of birds in their production of immunoglobulin upon appropriate stimulation.Gene Expression: The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.Perforin: A calcium-dependent pore-forming protein synthesized in cytolytic LYMPHOCYTES and sequestered in secretory granules. Upon immunological reaction between a cytolytic lymphocyte and a target cell, perforin is released at the plasma membrane and polymerizes into transmembrane tubules (forming pores) which lead to death of a target cell.Viral Proteins: Proteins found in any species of virus.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Tumor Cells, Cultured: Cells grown in vitro from neoplastic tissue. If they can be established as a TUMOR CELL LINE, they can be propagated in cell culture indefinitely.Sheep: Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.Staphylococcus aureus: Potentially pathogenic bacteria found in nasal membranes, skin, hair follicles, and perineum of warm-blooded animals. They may cause a wide range of infections and intoxications.Guinea Pigs: A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.Edetic Acid: A chelating agent that sequesters a variety of polyvalent cations such as CALCIUM. It is used in pharmaceutical manufacturing and as a food additive.Chromium Radioisotopes: Unstable isotopes of chromium that decay or disintegrate emitting radiation. Cr atoms with atomic weights of 46-49, 51, 55, and 56 are radioactive chromium isotopes.Inflammation: A pathological process characterized by injury or destruction of tissues caused by a variety of cytologic and chemical reactions. It is usually manifested by typical signs of pain, heat, redness, swelling, and loss of function.Cricetinae: A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.Restriction Mapping: Use of restriction endonucleases to analyze and generate a physical map of genomes, genes, or other segments of DNA.Lipopolysaccharides: Lipid-containing polysaccharides which are endotoxins and important group-specific antigens. They are often derived from the cell wall of gram-negative bacteria and induce immunoglobulin secretion. The lipopolysaccharide molecule consists of three parts: LIPID A, core polysaccharide, and O-specific chains (O ANTIGENS). When derived from Escherichia coli, lipopolysaccharides serve as polyclonal B-cell mitogens commonly used in laboratory immunology. (From Dorland, 28th ed)Macular Degeneration: Degenerative changes in the RETINA usually of older adults which results in a loss of vision in the center of the visual field (the MACULA LUTEA) because of damage to the retina. It occurs in dry and wet forms.Transfection: The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.DNA Primers: Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.Cell Survival: The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.DNA, Bacterial: Deoxyribonucleic acid that makes up the genetic material of bacteria.Peptides, Cyclic: Peptides whose amino and carboxy ends are linked together with a peptide bond forming a circular chain. Some of them are ANTI-INFECTIVE AGENTS. Some of them are biosynthesized non-ribosomally (PEPTIDE BIOSYNTHESIS, NON-RIBOSOMAL).Autolysis: The spontaneous disintegration of tissues or cells by the action of their own autogenous enzymes.Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.Muramidase: A basic enzyme that is present in saliva, tears, egg white, and many animal fluids. It functions as an antibacterial agent. The enzyme catalyzes the hydrolysis of 1,4-beta-linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in peptidoglycan and between N-acetyl-D-glucosamine residues in chitodextrin. EC 3.2.1.17.Immunoelectrophoresis: A technique that combines protein electrophoresis and double immunodiffusion. In this procedure proteins are first separated by gel electrophoresis (usually agarose), then made visible by immunodiffusion of specific antibodies. A distinct elliptical precipitin arc results for each protein detectable by the antisera.Receptors, IgG: Specific molecular sites on the surface of various cells, including B-lymphocytes and macrophages, that combine with IMMUNOGLOBULIN Gs. Three subclasses exist: Fc gamma RI (the CD64 antigen, a low affinity receptor), Fc gamma RII (the CD32 antigen, a high affinity receptor), and Fc gamma RIII (the CD16 antigen, a low affinity receptor).Structure-Activity Relationship: The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.Antibodies, Bacterial: Immunoglobulins produced in a response to BACTERIAL ANTIGENS.Genes, Bacterial: The functional hereditary units of BACTERIA.Immune Adherence Reaction: A method for the detection of very small quantities of antibody in which the antigen-antibody-complement complex adheres to indicator cells, usually primate erythrocytes or nonprimate blood platelets. The reaction is dependent on the number of bound C3 molecules on the C3b receptor sites of the indicator cell.Biological Markers: Measurable and quantifiable biological parameters (e.g., specific enzyme concentration, specific hormone concentration, specific gene phenotype distribution in a population, presence of biological substances) which serve as indices for health- and physiology-related assessments, such as disease risk, psychiatric disorders, environmental exposure and its effects, disease diagnosis, metabolic processes, substance abuse, pregnancy, cell line development, epidemiologic studies, etc.Antibodies, Antinuclear: Autoantibodies directed against various nuclear antigens including DNA, RNA, histones, acidic nuclear proteins, or complexes of these molecular elements. Antinuclear antibodies are found in systemic autoimmune diseases including systemic lupus erythematosus, Sjogren's syndrome, scleroderma, polymyositis, and mixed connective tissue disease.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.Haptoglobins: Plasma glycoproteins that form a stable complex with hemoglobin to aid the recycling of heme iron. They are encoded in man by a gene on the short arm of chromosome 16.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Antibody Specificity: The property of antibodies which enables them to react with some ANTIGENIC DETERMINANTS and not with others. Specificity is dependent on chemical composition, physical forces, and molecular structure at the binding site.Lupus Nephritis: Glomerulonephritis associated with autoimmune disease SYSTEMIC LUPUS ERYTHEMATOSUS. Lupus nephritis is histologically classified into 6 classes: class I - normal glomeruli, class II - pure mesangial alterations, class III - focal segmental glomerulonephritis, class IV - diffuse glomerulonephritis, class V - diffuse membranous glomerulonephritis, and class VI - advanced sclerosing glomerulonephritis (The World Health Organization classification 1982).Fibrinogen: Plasma glycoprotein clotted by thrombin, composed of a dimer of three non-identical pairs of polypeptide chains (alpha, beta, gamma) held together by disulfide bonds. Fibrinogen clotting is a sol-gel change involving complex molecular arrangements: whereas fibrinogen is cleaved by thrombin to form polypeptides A and B, the proteolytic action of other enzymes yields different fibrinogen degradation products.Antibody Formation: The production of ANTIBODIES by proliferating and differentiated B-LYMPHOCYTES under stimulation by ANTIGENS.Antigen-Antibody Reactions: The processes triggered by interactions of ANTIBODIES with their ANTIGENS.Antibodies, Bispecific: Antibodies, often monoclonal, in which the two antigen-binding sites are specific for separate ANTIGENIC DETERMINANTS. They are artificial antibodies produced by chemical crosslinking, fusion of HYBRIDOMA cells, or by molecular genetic techniques. They function as the main mediators of targeted cellular cytotoxicity and have been shown to be efficient in the targeting of drugs, toxins, radiolabeled haptens, and effector cells to diseased tissue, primarily tumors.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Gene Deletion: A genetic rearrangement through loss of segments of DNA or RNA, bringing sequences which are normally separated into close proximity. This deletion may be detected using cytogenetic techniques and can also be inferred from the phenotype, indicating a deletion at one specific locus.Lymphocytes: White blood cells formed in the body's lymphoid tissue. The nucleus is round or ovoid with coarse, irregularly clumped chromatin while the cytoplasm is typically pale blue with azurophilic (if any) granules. Most lymphocytes can be classified as either T or B (with subpopulations of each), or NATURAL KILLER CELLS.Streptococcus pneumoniae: A gram-positive organism found in the upper respiratory tract, inflammatory exudates, and various body fluids of normal and/or diseased humans and, rarely, domestic animals.PeptidoglycanInterferon-gamma: The major interferon produced by mitogenically or antigenically stimulated LYMPHOCYTES. It is structurally different from TYPE I INTERFERON and its major activity is immunoregulation. It has been implicated in the expression of CLASS II HISTOCOMPATIBILITY ANTIGENS in cells that do not normally produce them, leading to AUTOIMMUNE DISEASES.Cytokines: Non-antibody proteins secreted by inflammatory leukocytes and some non-leukocytic cells, that act as intercellular mediators. They differ from classical hormones in that they are produced by a number of tissue or cell types rather than by specialized glands. They generally act locally in a paracrine or autocrine rather than endocrine manner.Cell Death: The termination of the cell's ability to carry out vital functions such as metabolism, growth, reproduction, responsiveness, and adaptability.

*Complement system

... which causes osmotic lysis of the target cell. Kupffer cells and other macrophage cell types help clear complement-coated ... When complement is activated on a cell surface, the activation is limited by endogenous complement regulatory proteins, which ... which can then split C4 into C4a and C4b and C2 into C2a and C2b. C4b and C2a then bind together to form the classical C3- ... Polymorphisms of complement component 3, complement factor B, and complement factor I, as well as deletion of complement factor ...

*Classical complement pathway

... inducing cell lysis and death. The classical complement pathway can also be activated by apoptotic cells, necrotic cells, and ... Immunotherapies have been developed to detect and destroy cells infected by the HIV virus via classical complement activation. ... The activated C1s cleaves C4 into C4a and C4b, and C2 into C2a and C2b. The larger and active fragments, C4b and C2b form ... Therapies that utilize classical complement activation have been shown to be effective in targeting and killing cancer cells ...

*C3-convertase

DAF protects host cells from damage by autologous complement. DAF acts on C2b and Bb and dissociates them rapidly from C4b and ... Hourcade D, Holers VM, Atkinson JP (1989). "The regulators of complement activation (RCA) gene cluster". Adv Immunol. Advances ... C5 convertase formation and cell lysis. C3 convertase can be used to refer to the form produced in the alternative pathway ( ... The smaller C2a produced by C2 hydrolysis can then attach to the C4b to form the classical C3 convertase. The fragments C4a and ...

*Complement component 4

... leading to invading cell disruption and eventual lysis. In the classical pathway, the complement component-hereafter ... complement activation with a more extensive range of Ab-Ag complexes formed upon infections). Though interestingly, at this ... and C2a remaining in association with C4b; the C4b-C2a complex of the two proteins then exhibits a further system-associated ... December 2007). "The classical complement cascade mediates CNS synapse elimination". Cell. 131 (6): 1164-78. doi:10.1016/j.cell ...
... is produced by our E.coli expression system and the target gene encoding Asn679-Arg755 is expressed.
We have examined the relative roles of the macrophage (M phi) plasma membrane receptor for the cleaved third complement component (iC3b, CR3) and of the mannosyl/fucosyl receptor (MFR) in binding and ingestion of Leishmania donovani. In the absence of exogenous complement, the binding and ingestion of promastigotes, which are good activators of the ...
It is the practice of Ken Rodgers to personally meet with his potential clients and to give them advice about what to do following any serious injury. Generally the Law Office of Kenneth M. Rodgers represents injured persons under a Contingent Fee Agreement which means that there is no fee for the initial meeting and no fee for the legal work that must be undertaken to produce a recovery unless and until a recovery results. In the event that under the rules ...
Complement C3-C5 Convertases: Serine proteases that cleave COMPLEMENT C3 into COMPLEMENT C3A and COMPLEMENT C3B, or cleave COMPLEMENT C5 into COMPLEMENT C5A and COMPLEMENT C5B. These include the different forms of C3/C5 convertases in the ...
AB - A fundamental dilemma of steroid hormone regulation is how specific transcription is attained in vivo when several receptors recognize the same DNA sequence in vitro. We have identified an enhancer of the mouse sex-limited protein (Slp) gene that
CD11b (integrin alphaM subunit) is a 165-170 kDa type I transmembrane glycoprotein that non-covalently associates with integrin beta2 subunit (CD18); expression of the CD11b chain on the cell surface requires the presence of the CD18 antigen. CD11b/CD18 integrin (Mac-1, CR3) is highly expressed on NK cells, neutrophils, monocytes and less on macrophages. ...
CD11b (integrin alphaM subunit) is a 165-170 kDa type I transmembrane glycoprotein that non-covalently associates with integrin beta2 subunit (CD18); expression of the CD11b chain on the cell surface requires the presence of the CD18 antigen. CD11b/CD18 integrin (Mac-1, CR3) is highly expressed on NK cells, neutrophils, monocytes and less on macrophages. ...
wistar complement wistar rat complement serum | order wistar complement wistar rat complement serum | How to use: wistar complement wistar rat complement serum | su
wistar complement wistar rat complement serum | order wistar complement wistar rat complement serum | How to use: wistar complement wistar rat complement serum | su
Test results may vary depending on your age, gender, health history, the method used for the test, and other things. Your test results may not mean you have a problem. Ask your healthcare provider what your test results mean for you. The normal range for a complement C4 blood test is 16 to 48 milligrams per deciliter (mg/dL), or 0.16 to 0.48 grams per liter (g/L). Your complement levels will often shoot up dramatically just after an ...
A complement receptor is a receptor of the complement system, part of the innate immune system. Complement receptors bind proteins of the complement system, and can thus detect pathogens without mediation by antibodies. Complement activity is not antigen sensitive, but can be triggered by specific antigens. Many white blood cells express ...
Rodgers & Hammerstein: Hello Young Lovers (ARTPNO, Rodgers & Hammerstein, Oscar Hammerstein II, Richard Rodgers, Stevie Wonder, Hal Leonard, Digital Sheet Music, 15 July 2016, 21, smd_h_1182849O3JM4pXCr8) en-GB
GREEN BAY, Wis. - Aaron Rodgers threw for 326 yards and three touchdowns, Davante Adams and Ty Montgomery emerged as playmakers in the second half, and the Green Bay Packers beat the offensively challenged Chicago Bears, 26-10, on Thursday night.. Rodgers was 39 of 56, setting a franchise record for completions in a game in the Packers first contest without ...
According to The Rodgers and Hammerstein encyclopedia this is the last lyric that Lorenz Hart wrote but this is not totaly true: for the revival of A Connecticut Yankee Rodgers asked Hart to write some new material to make the show more apealing (Herbert Fields wrote a new book as well), even if the partnership with Hart was already broken (in 1942 Rodgers worte Oklahoma! with Oscar ...
TY - JOUR. T1 - Complement activation in acquired and hereditary amyloid neuropathy. AU - Hafer-Macko, Charlene E.. AU - Dyck, Peter J. AU - Koski, Carol Lee. PY - 2000. Y1 - 2000. N2 - The pathogenesis of the axonal degeneration in acquired or hereditary amyloidosis is unknown. In this immunohistochemistry study, we examined 20 sural nerve biopsies from individuals with amyloid ...
Human umbilical vein endothelial cells grown in vitro under standard conditions contain a high level of mRNA specific for the complement regulatory factors H and I. An additional 1.8-kb mRNA encoding a truncated form of factor H is also present. IFN-gamma stimulation of the cells causes a 6-7 fold ...
Abstract: : Purpose: Terminal complement components (C5,C5b-9)and several complement inhibitors are ubiquitous drusen components. This implies that complement activation may be a key element in drusen formation; but the specific complement activator(s) and activation pathway ...
highlighting the link between complement gene expression and IQ, in both schizophrenic patients and healthy controls. The study demonstrated a broad association between variations in complement gene expression and perturbed neurodevelopment. We were particularly interested to see that the final sentence of the paper stated that When complement gene-sets are taken as a whole, ...
Prior absorption of normal human serum (NHS) or C2-deficient human serum (C2D) with zymosan at 0 degrees C results in diminished consumption of C3 and factor B during subsequent incubation of the sera in Mg-EGTA buffer with zymosan at 37 degrees C for 30 min. An acid eluate from the zymosan restores the defect of absorbed NHS and C2D, and also enhances C3 and ...
Purpose.: Increasing evidence supports a role for complement in the pathogenesis of age-related macular degeneration (AMD). This study evaluated retinal microglia, T-lymphocytes, and complement deposition in a light-induced retinopathy model. The effect of a serotonin (5-hydroxytryptamine, 5-HT1A) agonist on these processes was investigated. Methods.: Rats were dark ...
Looking for online definition of Complement factor b in the Medical Dictionary? Complement factor b explanation free. What is Complement factor b? Meaning of Complement factor b medical term. What does Complement factor b mean?
Enhanced classical complement pathway activation and altered phagocytosis signaling molecules in human epilepsy. Exp Neurol. 2017 Jun 07;: Authors: Wyatt SK, Witt T, Barbaro NM, Cohen-Gadol AA, Brewster AL Abstract Microglia-mediated neuroinflammation is widely associated with seizures ...
Human Proximal Tubular Epithelial Cells from Creative Bioarray are isolated from normal human proximal tubular tissue. Human Proximal Tubular Epithelial Cells are grown in T25 tissue culture flasks pre-coated with gelatin-based coating solution for 2 min and incubated in Creative Bioarrays Culture Complete Growth Medium ...
TY - JOUR. T1 - Immunoglobulin G monoclonal antibodies to Cryptococcus neoformans protect mice deficient in complement component C3. AU - Shapiro, Scott. AU - Beenhouwer, David O.. AU - Feldmesser, Marta. AU - Taborda, Carlos. AU - Carroll, Michael C.. AU - Casadevall, Arturo. AU - ...
The complement system is an enzyme cascade that is a collection of blood and cell surface proteins to help the abilities of antibodies to clear pathogens from an organism. The complement system that comprises 30 different proteins, including serum proteins, serosal proteins, and cell membrane receptors is an important part of the innate ...
TY - JOUR. T1 - Critical role for serum opsonins and complement receptors CR3 (CD11b/CD18) and CR4 (CD11c/CD18) in phagocytosis of Francisella tularensis by human dendritic cells (DC). T2 - Uptake of Francisella leads to activation of immature DC and intracellular survival ...
The optimal reaction conditions for hemolytic assay of alternative complement pathway activity in mouse serum were investigated. A microtiter system was used, in which a number of 7.5×106 rabbit erythrocytes per test well appeared to be optimal. Rabbit erythrocytes were superior as target cells over erythtocytes from a number of ... read more other animal ...
Background: Vascular endothelial cells (ECs) express and release protein components of the complement pathways, as well as secreting and anchoring ultra-large von Willebrand factor (ULVWF) multimers in long string-like structures that initiate platelet adhesion during hemostasis and thrombosis. The alternative complement ...
What is Complement Component Gene? Definition of Complement Component Gene. Complement Component Gene FAQ. Learn more about Complement Component Gene. Complement Component Gene facts.
BACKGROUND Recently published data suggest that hormone replacement therapy (HRT) may increase cardiovascular risk during the early months of therapy. Activation of the immune system is known to be involved in several types of cardiovascular disease. In this cross-sectional study, serum C3, C4, IgG and IgM levels were evaluated in healthy ...
In this study, we showed that blocking complement activation accelerates the early healing rate in a mouse model of cutaneous wound healing. We also found that the components of the complement system responsible for this effect include C3, C5, and signaling through C5aR1, but not C5aR2 or C3aR. Furthermore, reconstitution of ...
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Being a major first line of immune defense, the complement system keeps a constant vigil against viruses. Its ability to recognize a large panoply of viruses and virus-infected cells, and trigger the effector pathways, results in neutralization of viruses and killing of the infected cells. This selection pressure exerted by complement on viruses has made them evolve a multitude of ...
Title: CH50: A Revisited Hemolytic Complement Consumption Assay for Evaluation of Nanoparticles and Blood Plasma Protein Interaction. VOLUME: 8 ISSUE: 3. Author(s):Ameena Meerasa, Jasper G. Huang and Frank X. Gu. Affiliation:Department of Chemical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1.. Keywords:CH50 ...
The neuronal microtubule-associated protein tau becomes hyperphosphorylated and forms aggregates in tauopathies but the processes leading to this pathological hallmark are not understood. Because tauopathies are accompanied by neuroinflammation and the complement cascade forms a key innate immune ...
AMD is strongly associated with the over-activation of complement pathways [16]. Supporting evidence comes from the detection of various complement proteins in the drusen of patients with AMD [9] and the close association between AMD and the alternative pathway. Furthermore, the association of genetic variants in ...
AMYNDAS is developing a novel peptidic complement inhibitor AMY-101, based on the third-generation compstatin analogue Cp40. AMY-101 is a selective inhibitor of complement activation in humans and in NHP. It binds to the complement component C3, the central functional hub that controls the upstream ...
Activation of the complement cascade is clearly implicated in the pathology of multiple sclerosis (MS). However, the extent and nature of its involvement in specific athological processes remains uncertain. We describe a detailed immunohistochemical study to localise a strategically selected set of ...
Objective: Complement proteins have been associated with atherosclerosis and cardiovascular risk factors. Recent data suggest a potential role of complement protein C3 in clot stability with hypofibrinolytic and prothrombotic features. Women after menopause are at greater risk of ...
The complement system is an important part of the humoral response in innate immunity, consisting of three different pathways. The third complement
Aim: Here we investigated the role of complement activation in phagocytosis and the release of cytokines and chemokines in response to two clinical isolates: Borrelia afzelii K78, which is resistant to complement-mediated lysis, and Borrelia garinii LU59, which is complement-sensitive.. Methods: Borrelia spirochetes were incubated in hirudin ...
The complement system is a potent effector of innate immunity. To elucidate the pathophysiological role of the complement system in inflammatory bowel disease (IBD), we evaluated the development of dextran sulfate sodium (DSS)-induced colitis in genetically complement C5-deficient mice. We used DBA2/J mice, which are genetically deficient in ...
Atypical hemolytic uremic syndrome (aHUS) is frequently associated in humans with loss-of-function mutations in complement-regulating proteins or gain-of-function mutations in complement-activating proteins. Thus, aHUS provides an archetypal complement-mediated disease with which to model new therapeutic strategies and ...
OP28 The complement component C3 is expressed by the endometrial ectopic tissue and is involved in the endometriotic lesion formation C. Agostinis 1, G. Zito 1, D. De Santo1, R. Vidergar2, O. Radillo 1, F. Bossi 1, S. Zorzet2, G. Ricci 1, R. Bulla 2 1 Institute for Maternal and Child Health, IRCCS Burlo Garofolo, Trieste, Italy 2 Department of Life Sciences, University of Trieste, Trieste, Italy E-mail address: ...
Purpose The purpose of this study was to investigate complement activation and associated inflammatory mechanisms in normal, aged human retina. in the choriocapillaris, and in BM. Lectin binding of RCA-I was Rabbit polyclonal to CREB1 strong throughout the neuroretina. Conclusions Robust immunostaining for APP in older donor eyes suggested ...
The surface plasmon resonance (SPR) phenomenon is utilized in a number of new real time biosensors. In this study, we have used this technique to study interactions between the central complement component C3b and its multiple ligands by using the Biacore equipment. The SPR technique is particularly suitable for analysis of the alternative complement pathway (AP) ...
C1-INH is a heavily glycosylated, single chain, plasma glycoprotein with an apparent molecular weight of 105 kd on sodium dodecyl sulfate-PAGE. It consists of 478 amino acids comprising a backbone molecular weight of 52,880 (1). The protein acts as a serine protease inhibitor (serpin) binding to and forming covalent bonds with a variety of ...
The complement system is a major humoral component of vertebrate defenses for tagging and killing target microorganisms. Recent molecular analyses have uncovered a striking feature of bony fish complement, namely that several complement components are encoded by multiple genes. In this review, the structural diversity of C3, C4, C5, ...
A casein kinase released from activated human platelets has been shown to phosphorylate a number of plasma proteins. When platelets are activated they release substantial amounts of ATP and divalent cations which are necessary for phosphorylation of proteins. The aim of this study was to elucidate the optimal conditions for ...
Background Glaucoma is an age-related neurodegenerative disorder involving the loss of retinal ganglion cells (RGCs), which results in blindness. Studies in animal models have shown that activation of inflammatory processes occurs early in the disease. In particular, the complement cascade is ...
Ischemia and reperfusion of organs is an unavoidable consequence of transplantation. Inflammatory events associated with reperfusion injury are in part attributed to excessive complement activation. Systemic administration of complement inhibitors reduces reperfusion injury but leaves patients vulnerable to infection. Here, we report a novel ...
The complement system provides a fundamental component of the body's immune response to invading microorganisms. This chapter highlights the various roles of the complement system in the orchestration of the immune response towards microbial infections, gives examples of microbial strategies to evade complement-mediated clearance, and discusses how ...
Each pathway follows a sequence of reactions to generate a protease called a C3 convertase. The active protease is retained at the pathogen surface, and this ensures that the next complement zymogen in the pathway is also cleaved and activated at the pathogen surface. By ...
TY - JOUR. T1 - Risk of non-Hodgkin lymphoma in association with germline variation in complement genes. AU - Cerhan, James R. AU - Novak, Anne J. AU - Fredericksen, Zachary S.. AU - Wang, Alice H.. AU - Liebow, Mark. AU - Call, Timothy G.. AU - Dogan, Ahmet. AU - Witzig, Thomas Elmer. AU - Ansell, Stephen Maxted. AU - ...
C5a is a protein fragment released from cleavage of complement component C5 by protease C5-convertase into C5a and C5b fragments. C5b is important in late events of the complement cascade, an orderly series of reactions which coordinates several basic defense mechanisms, ...
Membranoproliferative glomerulonephritis (MPGN) is a relatively-rare, immune-mediated glomerular disease. There is no accepted therapy and all current therapies are inadequate. Current therapeutic options include immunosuppression with corticosteroids alone or in combination with alkylating agents, antiplatelet therapy with aspirin and/or dipyridamole and/or ...
Fulminant meningococcal sepsis has been termed the prototypical lipopolysaccharide (LPS)-mediated gram-negative septic shock. Systemic inflammation by activated complement and cytokines is important in the pathogenesis of this disease. We investigated the involvement of meningococcal LPS in complement ...
Looking for Complement system? Find out information about Complement system. The sequential activation of complement proteins resulting in lysis of a target cell Explanation of Complement system
Properdin or complement factor P is a conserved serum glycoprotein of the immune defence. It plays a role in strengthening the activation of complement, a system of proteins essential in the first line defence against infection. Properdin is the only positive regulator and plays a major role in regulating the alternative pathway of the complement system, an ...
... The activated complement system recognizes and eliminates invading microorganisms and thus is beneficial for the host.
Complement component C9 binds to the C5b-8 complex as the final protein of the membrane attack complex. After binding, it undergoes a conformational change and inserts itself into the cell membrane, forming transmembrane channels.
Rooryck C, Diaz-Font A, Osborn DP, Chabchoub E, Hernandez-Hernandez V, Shamseldin H, Kenny J, Waters A, Jenkins D, Kaissi AA, Leal GF, Dallapiccola B, Carnevale F, Bitner-Glindzicz M, Lees M, Hennekam R, Stanier P, Burns AJ, Peeters H, Alkuraya FS, Beales PL. Mutations in lectin complement pathway genes COLEC11 ...
We reported inhibition of growth of primary rat mammary carcinomas after infusions of tumor-bearer plasma absorbed with Protein A-Sepharose or inactivated CNBr Sepharose. Absorbed plasmas were depleted of the third component of complement (C3) (other complement components defined similarly) and C5 but not C1, C4, or C2. These results suggested that ...
This gene is a member of a small complement factor H (CFH) gene cluster on chromosome 1. Each member of this gene family contains multiple short consensus repeats (SCRs) typical of regulators of complement activation. The protein encoded by this gene has nine SCRs with the first two repeats having heparin binding properties, a region within repeats 5-7 having ...
A Novel Protocol Allowing Oral Delivery of a Protein Complement Inhibitor that Subsequently Targets to Inflamed Colon Mucosa and Ameliorates Murine Colitis. Elvington, M; Blichmann, P; Qiao, F; Scheiber, M; Wadsworth, C; et al. A novel protocol allowing oral delivery of a protein complement inhibitor that subsequently targets to inflamed colon mucosa ...
Secretion of complement component C3 by U937 cells was studied. Preliminary evidence for a cell-associated proteolytic activity specific for C3 is given, as well as for a covalent-like binding of C3 fragments to the cell membranes. Secretion of C3, in the presence of 10 ng of phorbol 12-myristate 13-acetate/ml, is 120-140 ng/10(6) ...
When I started my business in 1977, Theological College purchased the first Rodgers Organ I installed. The chapel was larger then and had very favorable acoustics. Father Lobo, P.S.S., who was rector at that time, was a wonderful friend and supporter. He allowed us to bring prospective organ customers to see and hear that excellent example of our work. His kindness is one of my fondest ...
Packers quarterback Aaron Rodgers (shoulder) remains under medical evaluation, coach Mike McCarthy said. No decision has been made on when he might return to playing.
Its a scenario most Packers fans dont want to think about but one coaches and front office personnel must prepare for. If the disastrous happens, Milwaukee Journal Sentinel writer Bob McGinn thinks Green Bay would be ready for life without Rodgers.
Its a scenario most Packers fans dont want to think about but one coaches and front office personnel must prepare for. If the disastrous happens, Milwaukee Journal Sentinel writer Bob McGinn thinks Green Bay would be ready for life without Rodgers.
We previously described a simplified quantitative hemolytic assay for classical pathway (CP) hemolytic function in serum that has been shown to correlate with the 50% hemolytic complement (CH50) assay. In the present study, we used this assay to compare CP functions; plasma levels of C3, C4, and C3dg; and ratios of ...
The structure of the human C5aR antagonist, C5a-A8, reveals a three-helix bundle conformation similar to that observed for human C5a-desArg, whereas murine C5a and C5a-desArg both form the canonical four-helix bundle. These conformational differences are discussed in light of the differential C5aR ...
Cerebral IR injury produces a profound inflammatory response characterized by neutrophil, macrophage, and platelet accumulation, upregulation of adhesion molecules, blood-brain barrier destruction, and cytokine production.5 During central nervous system inflammation, complement activation plays a direct role ...
A specific hypoglycosylated isoform of the complement regulator membrane cofactor protein (MCP; CD46) is expressed on the inner acrosomal membrane (IAM) of spermatozoa. This membrane is exposed after the acrosome reaction, an exocytosis event that occurs upon contact with the zona pellucida. We initiated this investigation ...
A specific hypoglycosylated isoform of the complement regulator membrane cofactor protein (MCP; CD46) is expressed on the inner acrosomal membrane (IAM) of spermatozoa. This membrane is exposed after the acrosome reaction, an exocytosis event that occurs upon contact with the zona pellucida. We initiated this investigation ...
A new cluster of complement component genes, including C4BP, C3bR, and FH, is described. Family segregation data indicate that FH is linked to the genes for C4-bp and C4bR, previously reported to be linked and to maintain linkage disequilibrium. This cluster is not linked to the major histocompatibility complex, which contains the genes for the complement components, C4, ...
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Radioimmune assays were developed to assay the binding of complement components C1q, C1s and C4 to antibody aggregates and to cell-bound antibody. The binding of the components was compared with the haemolytic activity and with the capacity to form the C3 convertase activity in the presence of excess C2. The ...
The present invention provides modified IgG3 containing human constant regions which has a shorter total-hinge region compared with normal human IgG3. Also described is a method for assaying an antibody against a specific antigen or hapten for its effectiveness in complement activation in an animal species, wherein the antibody is ...
Kőhalmi, Kinga Viktória and Veszeli, Nóra and Luczay, Andrea and Varga, Lilian and Farkas, Henriette (2017) A danazolkezelés hatása C1-inhibitor-hiány okozta hereditaer angiooedemás gyermekek növekedésére , Effect of danazol treatment on growth in pediatric patients with hereditary angioedema due to C1-inhibitor deficiency. Orvosi Hetilap, ...
Outer retinal and renal glomerular functions rely on specialized vasculature maintained by VEGF that is produced by neighboring epithelial cells, the retinal pigment epithelium (RPE) and podocytes, respectively. Dysregulation of RPE- and podocyte-derived VEGF is associated with neovascularization in wet age-related macular degeneration (ARMD), ...
Outer retinal and renal glomerular functions rely on specialized vasculature maintained by VEGF that is produced by neighboring epithelial cells, the retinal pigment epithelium (RPE) and podocytes, respectively. Dysregulation of RPE- and podocyte-derived VEGF is associated with neovascularization in wet age-related macular degeneration (ARMD), ...
This gene encodes a serine protease that functions as a component of the lectin pathway of complement activation. The complement pathway plays an essential role in the innate and adaptive immune response. The encoded protein is synthesized as a zymogen and is activated when it complexes with the pathogen recognition ...
A method and a package for identifying single nucleotide polymorphisms in complement receptor is useful in identifying individual susceptibility to a disease. Complement receptors CR1 and CR2 are active in the immune response and autoimmune diseases. The susceptibility and severity of autoimmune disease is determined by genotyping or phenotyping an individual for complement ...
Host defense mechanisms can counteract the antiphagocytic bacterial capsule. Unlike classical complement pathway, the alternative complement pathway is not antibody-mediated and can easily overwhelm encapsulated bacteria. It is triggered by the ...
TY - JOUR. T1 - Decay accelerating factor regulates complement activation on glomerular epithelial cells. AU - Quigg, R. J.. AU - Nicholson-Weller, A.. AU - Cybulsky, A. V.. AU - Badalamenti, John. AU - Salant, D. J.. PY - 1989. Y1 - 1989. N2 - Epithelial cells of the glomerular capillary are the site of ...
Severe forms of chronic periodontitis affect up to 10% of adults. Tumour necrosis factor and lymphotoxin-alpha genes in the major histocompatibility complex are associated with severe periodontitis. Complement factor C4 is a nearby, polymorphic, functionally relevant gene region. Although associated with chronic mucosal infections, ...
TY - JOUR. T1 - Low serum complement 3 level is associated with severe ANCA-associated vasculitis at diagnosis. AU - Choi, Hyeok. AU - Kim, Youhyun. AU - Jung, Seung Min. AU - Song, Jason Jungsik. AU - Park, Yong Beom. AU - Lee, Sang Won. PY - 2019/2/15. Y1 - 2019/2/15. N2 - Objectives: We investigated whether low serum C3 level can cross-sectionally estimate severe antineutrophil ...
The first indication is paroxysmal nocturnal hemoglobinuria (PNH), a rare disease of the bone marrow. Apellis drug candidate APL-2, an inhibitor of complement component C3, is designed to provide PNH patients with an alternative to the current standard-of-care. In its second program, Apellis is testing whether APL-1, another inhibitor of complement ...
Membranoproliferative glomerulonephritis (MPGN) is inflammation of the filtering units of the kidney (glomerulonephritis or GN) that occurs with activation of the complement system of immunity. The Complement System The complement system of proteins provides immunity through 2 pathways. In the classical pathway (blue half of cartoon), an antigen-antibody forms an immune complex that ...
There is wide variation of infections associated with complement deficiency depending on which complement protein and activation pathway is affected(Skattum et al 2011). Some complement deficiencies caries risk of infection, other mainly associated with autoimmune diseases. Some genetic and ...
The complement system constitutes a critical component of the innate immune response. The lectin pathway is one of the three activation pathways of the complement activation cascade that can recognise and respond to structures on oxygen deprived cells and contribute to ischaemia ...
I have been |b|diagnosed to have idiopathic membranoproliferative glomerulonephritis (MPGN)|/b| Type 1. I am taking one drug daily (Renitec- an ACE-inhibitor). What are your recommendations on my condition? Will this eventually lead to renal failure, even if I take the drug religiously? My 24-hour urine protein count is aroung 1.8 to 2g. Is this manageable? Is there a possibility that my protein count will normalize? What ...
Membranoproliferative glomerulonephritis (MPGN), also known as mesangiocapillary glomerulonephritis, is a pattern of glomerular injury viewed by light microscopy. Its name is derived from the characteristic histologic changes including hypercellulari
Pemphigoid gestationis (PG) is a skin condition that usually presents in the second trimester of pregnancy; however, it may occur at any time during the pregnancy, as well as in the days post-partum. PG was formerly called herpes gestationis, but it not related to the herpes virus. PG is caused by the production of autoantibodies to proteins found in the skin. It is not surprising that this condition occurs more frequently in those with other ...
SR GROUP - Exporter, Importer, Manufacturer, Distributor, Supplier, Trading Company of Rat CFH(Complement Factor H) ELISA Kit based in Delhi, India
Herpes Gestations is also commonly referred to as Pemphigoid Gestationis. Unlike what you may have heard, the condition is not linked to viruses. Herpes Gestationis is a rare condition that is typified with itchy feeling. The condition is an autoimmune infection that commonly occurs between the 3rd and 4th trimester. According to the CDC (Center […]. ...
The information concerning non-invasive, easily obtainable, and accurate biomarkers for diagnosis of lupus nephritis (LN) is extremely limited. The aim of this study was to evaluate the diagnostic performance of cystatin C (CysC) and complement component 1q (C1q) for LN. A case-control study that included 905 patients with ...
Twenty patients with invasive cervical cancer of the squamous cell type were treated by radiotherapy and/or radical hysterectomy. During a follow-up period of approximately 2 yr in 10 of these patients a recurrence was established. Serial determinations of three acute phase reactants (α1-acid glycoprotein, haptoglobin and ...
Eculizumab is a monoclonal antibody that prevents complement activation. It has been found to be an effective treatment for atypical hemolytic-uremic syndrome (aHUS). This retrospective study is the largest collection of previously published and unpublished cases to date. Eculizumab was effective at both preventing and treating ...

C2 Gene - GeneCards | CO2 Protein | CO2 AntibodyC2 Gene - GeneCards | CO2 Protein | CO2 Antibody

Complement C2, including: function, proteins, disorders, pathways, orthologs, and expression. GeneCards - The Human Gene ... This infers resistance to complement-mediated cell lysis, allowing parasite survival and infection. ... activated by C1r to form C2a and C2b,combining with C4A and C4B to form C3/C5 convertase,classical pathway of C3 activation *C2 ... Activated C1 cleaves C2 into C2a and C2b. The serine proteinase C2a then combines with complement factor 4b to create the C3 or ...
more infohttp://www.genecards.org/cgi-bin/carddisp.pl?gene=C2

Complement System: Pathways, Functions and Regulation - microbeonlineComplement System: Pathways, Functions and Regulation - microbeonline

... proteins lead to too much activation of complements in wrong time and place which leads to unwanted inflammation and cell lysis ... Now, C4b attracts C2 which is also cleaved into C2a and C2b. C2a binds C4b forming the C4b2a complex whereas C2b goes away. The ... Activation of mast cells and basophils and enhancement of inflammation. The proteolytic complement fragments, C5a, C4a, and C3a ... Various plasma and cell membrane proteins regulate complement activation by inhibiting different steps in the cascade. ...
more infohttps://microbeonline.com/complement-system-pathways-functions-regulation/amp/

Complement Pathways: Types, Functions and Regulation - MicrobeonlineComplement Pathways: Types, Functions and Regulation - Microbeonline

... proteins lead to too much activation of complements in wrong time and place which leads to unwanted inflammation and cell lysis ... Now, C4b attracts C2 which is also cleaved into C2a and C2b. C2a binds C4b forming the C4b2a complex whereas C2b goes away. The ... Activation of mast cells and basophils and enhancement of inflammation. The proteolytic complement fragments, C5a, C4a, and C3a ... Various plasma and cell membrane proteins regulate complement activation by inhibiting different steps in the cascade. ...
more infohttps://microbeonline.com/complement-system-pathways-functions-regulation/?share=google-plus-1

Complement Activation (Homo sapiens) - WikiPathwaysComplement Activation (Homo sapiens) - WikiPathways

Proteolytic Cleavage & Activation. Pathogenic Bacterial Cell. C4A. C9. DAF. C6. C8B. C5. MASP2. C1QG. C2A. H2O. C3. C8A. C1QA. ... C2A. C4B. C5 convertase. C5B. C1QB. C1QG. C1QA. C1R. C1S. C1 complex. C8G. H2O. Osmotic lysis. MASP1. ... Pathway:Human:Complement Activation Classical]] moved to [[Pathway:Homo sapiens:Complement Activation Classical]]: Renaming ... gpml file for [[Human:Complement_Activation_Classical]]. External references DataNodes. View all...", "View last 5...") style ...
more infohttps://www.wikipathways.org/index.php?title=Pathway:WP545&oldid=82136

Complement Activation (Homo sapiens) - WikiPathwaysComplement Activation (Homo sapiens) - WikiPathways

C2A. C4B. C5 convertase. C5B. C1QB. C1QG. C1QA. C1R. C1S. C1 complex. C8G. H2O. Osmotic lysis. ... which forms a channel for water to flood into the target cell, leading to osmotic lysis. ... Pathway:Human:Complement Activation Classical]] moved to [[Pathway:Homo sapiens:Complement Activation Classical]]: Renaming ... Proteolytic Cleavage & Activation. C8A. H2O. C1S. C4B. C8B. C5. C9. C1QB. C1QG. C4A. C1R. C1QA. C6. C7. MASP1. C3. C2A. DAF. C2 ...
more infohttps://www.wikipathways.org/index.php?title=Pathway:WP545&oldid=82133

Complement system - WikipediaComplement system - Wikipedia

... which causes osmotic lysis of the target cell. Kupffer cells and other macrophage cell types help clear complement-coated ... When complement is activated on a cell surface, the activation is limited by endogenous complement regulatory proteins, which ... which can then split C4 into C4a and C4b and C2 into C2a and C2b. C4b and C2a then bind together to form the classical C3- ... Polymorphisms of complement component 3, complement factor B, and complement factor I, as well as deletion of complement factor ...
more infohttps://en.wikipedia.org/wiki/Complement_system

Classical complement pathway - WikipediaClassical complement pathway - Wikipedia

... inducing cell lysis and death. The classical complement pathway can also be activated by apoptotic cells, necrotic cells, and ... Immunotherapies have been developed to detect and destroy cells infected by the HIV virus via classical complement activation. ... The activated C1s cleaves C4 into C4a and C4b, and C2 into C2a and C2b. The larger and active fragments, C4b and C2b form ... Therapies that utilize classical complement activation have been shown to be effective in targeting and killing cancer cells ...
more infohttps://en.wikipedia.org/wiki/Classical_complement_pathway

Immunology Lecture 7. Flashcards by Abbey Phelps | BrainscapeImmunology Lecture 7. Flashcards by Abbey Phelps | Brainscape

What does activation of the complement cascade result in? cell lysis, increased phagocytosis, increased vascular permeability, ... Otherwise there would always be activation - on human cells so those cells are not destroyed - bacteria cells do not have ... cleavage of C3 leading to the activation of a common sequence of events leading to cell lysis - c3b is left on surface of ... Which cell is an exception to all human cells have inhibitors to complement? ...
more infohttps://www.brainscape.com/flashcards/immunology-lecture-7-4030168/packs/5964050

Substrate recognition by complement convertases revealed in the C5-cobra venom factor complex | The EMBO JournalSubstrate recognition by complement convertases revealed in the C5-cobra venom factor complex | The EMBO Journal

Their proteolytic fragments mediate enhanced phagocytosis and pathogen lysis, clearance of immune complexes and apoptotic cells ... Complement activation and the structure of the C5-CVF complex. (A) The three activation pathways of complement (left) induce ... C4b2a is the widely used short‐hand nomenclature for the C4b-C2a complex in the complement field, and similar nomenclature is ... Rawal N, Rajagopalan R, Salvi VP (2008) Activation of complement component C5: comparison of C5 convertases of the lectin ...
more infohttp://emboj.embopress.org/content/30/3/606

Complement - PigComplement - Pig

Complement fragments (C2a C3a, C4a and especially C5a) released after complement activation are chemotactic for phagocytes and ... Cell Lysis. The components (C5 - C9) can kill pathogens directly by causing cell lysis. This is effective against encapsulated ... Complement Inhibitors. To prevent inappropriate activation of the complement system there is a range of control mechanisms/ ... Only IgM and certain IgG subclasses can activate complement this way. *Immune complexes trigger complement activation by ...
more infohttps://www.vetbook.org/wiki/pig/index.php/Complement

Formation of High-Affinity C5 Convertases of the Alternative Pathway of Complement | The Journal of ImmunologyFormation of High-Affinity C5 Convertases of the Alternative Pathway of Complement | The Journal of Immunology

... endothelial cells, eosinophils, neutrophils, and phagocytes to the site of complement activation (4, 5). ... Lysis of rabbit erythrocytes (ER) or sheep erythrocytes (ES) was shown to contribute ,2% to C5b,6 titers using lysis of EC as ... In the classical pathway C3 convertase C4b,C2a has a structure similar to the alternative pathway C3 convertase in having C2a ... Complement C3 convertase: cell surface restriction of BIH control and generation of restriction on neuraminidase treated cells ...
more infohttp://www.jimmunol.org/content/166/4/2635

Complement system - WikipediaComplement system - Wikipedia

... which causes osmotic lysis of the target cell. Kupffer cells and other macrophage cell types help clear complement-coated ... When complement is activated on a cell surface, the activation is limited by endogenous complement regulatory proteins, which ... Some sources designate the larger and smaller fragments as C2a and C2b respectively[13][14][15][16][17][18][19][20][21] while ... complement factor B, and complement factor I, as well as deletion of complement factor H-related 3 and complement factor H- ...
more infohttps://en.m.wikipedia.org/wiki/Complement_system

Complement system - wikidocComplement system - wikidoc

... which causes osmotic lysis of the target cell. Kupffer cells and other macrophage cell types help clear complement-coated ... The end result of this activation cascade is massive amplification of the response and activation of the cell-killing membrane ... which can then split C4 into C4a and C4b and C2 into C2a and C2b. C4b and C2a then bind together to form C3-convertase, as in ... Some complement control proteins are present on the membranes of self-cells preventing them from being targeted by complement. ...
more infohttps://www.wikidoc.org/index.php/Complement_system

Complement in Immune and Inflammatory Disorders: Pathophysiological Mechanisms | The Journal of ImmunologyComplement in Immune and Inflammatory Disorders: Pathophysiological Mechanisms | The Journal of Immunology

It becomes evident that excessive activation or insufficient control of complement activation on host cells can cause an immune ... that lyse susceptible cells (e.g., Gram-negative bacteria). Cleavage of C5 releases the chemokine C5a that, together with C3a, ... The enzymatic fragment of C2 is referred to as C2b in this review; the same fragment is sometimes designated as C2a in ... that favors complement activation on immune cells, local generation of C3a and C5a, enhanced T cell proliferation, and cytokine ...
more infohttp://www.jimmunol.org/content/190/8/3831

Frontiers | The Complement System: A Prey of Trypanosoma cruzi | MicrobiologyFrontiers | The Complement System: A Prey of Trypanosoma cruzi | Microbiology

... complement functions are generated which include opsonization and phagocytosis of particles or microorganisms and cell lysis. ... a key step in the activation of complement. Moreover, T. cruzi promotes secretion of plasma membrane-derived vesicles from host ... The complement consists of at least 35 or more plasma proteins and cell surface receptors/regulators, which can be activated by ... The complement consists of at least 35 or more plasma proteins and cell surface receptors/regulators, which can be activated by ...
more infohttps://www.frontiersin.org/articles/10.3389/fmicb.2017.00607/full

slides - Smith Labslides - Smith Lab

Lysis of bacteria, viruses, and cells that are damaged or infected. Opsonization & Phagocytosis • Complement activation ... C4 and continue the complement cascade Complement Regulation Complement Regulatory Proteins Found in Plasma C4BP displaces C2a ... 76-81 CFH mutations prevent binding of CFH to cell surface thereby causing unregulated Complement activation on the cell ... C-reactive protein activates complement • Apoptotic cells express phosphocholine on the cell surface which activates complement ...
more infohttp://slidegur.com/doc/111325/slides---smith-lab

Complement Activation PathwaysComplement Activation Pathways

The complement system that comprises 30 different proteins, including serum proteins, serosal proteins, and cell membrane ... There are three different complement pathways, the classical complement pathway, the alternative complement pathway, and the ... The complement system is an enzyme cascade that is a collection of blood and cell surface proteins to help the abilities of ... The complement system has four major function, including lysis of infectious organisms, activation of inflammation, ...
more infohttp://www.sinobiological.com/Complement-Activation-Pathways-a-1511.html?utm_source=genecards&utm_medium=platform&utm_campaign=genecards

ComplementComplement

Binds C5 for cleavage by C2a.. Binds cell surfaces for opsonization and activation of alternate pathway.. ... In addition, complement can neutralize virus particles either by direct lysis or by preventing viral penetration of host cells ... Complement. COMPONENTS AND FUNCTIONS OF THE COMPLEMENT SYSTEM The complement system found in the blood of mammals is composed ... Generally, only Gram-negative cells can be directly lysed by antibody plus complement; Gram-positive cells are mostly resistant ...
more infohttp://medmicro.atwebpages.com/cment.htm

Complement Activation PathwaysComplement Activation Pathways

The complement system that comprises 30 different proteins, including serum proteins, serosal proteins, and cell membrane ... There are three different complement pathways, the classical complement pathway, the alternative complement pathway, and the ... The complement system is an enzyme cascade that is a collection of blood and cell surface proteins to help the abilities of ... The complement system has four major function, including lysis of infectious organisms, activation of inflammation, ...
more infohttp://www.sinobiological.com/Complement-Activation-Pathways-a-1511.html

补体激活信号通路补体激活信号通路

The complement system has four major function, including lysis of infectious organisms, activation of inflammation, ... The complement system is an enzyme cascade that is a collection of blood and cell surface proteins to help the abilities of ... and forms C5 convertase in association with C4b and C2a. The generation of C5 convertase is the end of the classical pathway. ... The alternative complement pathway begins with the activation of C3 and requires factor B and factor D. All three pathways ...
more infohttp://cn.sinobiological.com/Complement-Activation-Pathways-a-1511.html

Complement System and Chronic Inflammation | Lecturio Medical LibraryComplement System and Chronic Inflammation | Lecturio Medical Library

Definition & function of the complement system ✓, complement activation ✓, mechanism of action of complement proteins ✓, ... you will learn everything about complement system and chronic inflammation and be perfectly prepared for your next exam. ... Activation and attachment of C3b to target cells leads to opsonization, which is rapid lysis and phagocytosis of the microbial ... IgA, IgD, IgE and IgG subclass 2 are not known to activate complement proteins. C4b and C2a form together C4b2a, which is known ...
more infohttps://www.lecturio.com/magazine/complement-system-chronic-inflammation/

Antibody-induced arthritis: disease mechanisms and genes involved at the effector phase of arthritis | Arthritis Research &...Antibody-induced arthritis: disease mechanisms and genes involved at the effector phase of arthritis | Arthritis Research &...

Neutrophils and macrophages are important inflammatory cells and the secretion of tumour necrosis factor-α and IL-1β is ... Both the complement and FcγR systems have been found to play essential roles. ... recruitment and activation of phagocytes; and in lysis (membrane attack complex). Complement factor 3 and, to an extent, factor ... AA, arachidonic acid; C1q, C2a, C3, C3a, C4b, C5a and B (factor B), complement components; CCL3, chemokine (C-C motif) ligand 3 ...
more infohttps://arthritis-research.biomedcentral.com/articles/10.1186/ar2089

The Complement System Andrew E Thompson MD FRCPC Fellow in Rheumatology University of British Columbia. -  ppt downloadThe Complement System Andrew E Thompson MD FRCPC Fellow in Rheumatology University of British Columbia. - ppt download

... permeability of capillary beds via mast cell and basophil activation - C3a & C5a (Anaphylatoxins) Cellular Lysis via the MAC ... Only IgG and IgM can activate complement -Once activated C1s is eventually cleaved which activates C4 and C2 -C4b & C2a come ... to a cell surface and ends with the lysis of the cell Begins with antibody binding to a cell surface and ends with the lysis of ... Presents to T-Cell -Autoreactive B-Cells take up antigen from apoptotic cells and (with the help CD4+ Th2-Cells) transform into ...
more infohttp://slideplayer.com/slide/3317721/

The complement systemThe complement system

At least 30 different complement proteins act sequentially to produce a wide ranges of activities, from cell lysis to ... The complement system is a collection of blood and cell surface proteins that is a major primary defense and a clearance ... The lipid bilayer of the cell or virus is disrupted.. Activation of inflammation - Several peptides produced by proteolytic ... on cell membrane performing MAC in the end.. Why C2 must be different from the others? Why C2 left C2a on membrane? Non-senses ...
more infohttp://www.virology.ws/2009/09/28/the-complement-system/

Eculizumab before and after allogeneic hematopoietic stem cell transplantation in a patient with paroxysmal nocturnal...Eculizumab before and after allogeneic hematopoietic stem cell transplantation in a patient with paroxysmal nocturnal...

Bone marrow transplantation Hematopoietic stem cell transplantation Hematopoietic stem cells Monoclonal antibodies Stem cells ... Eculizumab before and after allogeneic hematopoietic stem cell transplantation in a patient with paroxysmal nocturnal ... which results in red blood cell susceptibility to terminal complement-mediated lysis. CD55 inhibits complement at the C3 level ... It is the first approved drug that specifically targets complement activation (15). Herein we present a case with recurrent ...
more infohttps://www.thefreelibrary.com/Eculizumab+before+and+after+allogeneic+hematopoietic+stem+cell+...-a0305562374
  • C4b2a is the widely used short‐hand nomenclature for the C4b-C2a complex in the complement field, and similar nomenclature is used for the remaining complexes in the following). (embopress.org)
  • These contain a non‐catalytic substrate contacting subunit (C3b or C4b) in complex with a protease subunit (Bb or C2a). (embopress.org)
  • Both C3a and C5a have anaphylatoxin activity, directly triggering degranulation of mast cells as well as increasing vascular permeability and smooth muscle contraction. (wikidoc.org)
  • Vascular endothelial growth factor receptor-1, interleukin-6 and TNF-alpha are all released by complement activation leading to angiogenesis with the formation of new blood vessels . (lecturio.com)
  • C3a is the precursor of an important cytokine (adipokine) named ASP (although this is not universally accepted) and is usually rapidly cleaved by carboxypeptidase B. Both C3a and C5a have anaphylatoxin activity, directly triggering degranulation of mast cells as well as increasing vascular permeability and smooth muscle contraction. (technologynetworks.com)
  • When injected into target tissue encourages recruitment of C1q and activates downstream events, eventually leading to the formation of the C5b-9 complex which damages tumor cells, killing them. (wikipedia.org)
  • In fluid-phase activation, C3 spontaneously activates via hydrolysis to form C3 H2O -- since it is unstable, C3 H2O usually reverts to C3. (studentreader.com)
  • This is important for targeting the virus in its intracellular phase because the antibodies specific to the synthetic peptides can trigger the classical complement pathway and induce the death of HIV infected cells. (wikipedia.org)
  • Subsequent interactions between C5b and other terminal components C6, C7, C8, and C9 form the membrane attack complex or the C5b-9 complex which forms pores on the target cell membranes to lysing. (wikipedia.org)
  • Lysis - Polymerization of specific activated complement components on a foreign cell or enveloped virus leads to the formation of pores. (virology.ws)
  • Although the exact involvement of complement needs to be carefully investigated for each disease, therapeutic modulation of complement activity emerges as an attractive target for upstream inhibition of inflammatory processes. (jimmunol.org)
  • Combined Inhibition of Apoptosis and Complement Improves Neural Graft Survival of Embryonic Rat and Porcine Mesencephalon in the Rat Brain, Exp. (freepatentsonline.com)
  • Ehrlich believed that each antigen-specific amboceptor has its own specific complement, whereas Bordet believed that there is only one type of complement. (wikipedia.org)
  • Anaphlatoxin is a substance produced by complement activation that causes the release of histamine and other mediators of immediate hypersensitivity from basophils and mast cells, thereby producing signs and symptoms of immediate hypersensitivity (anaphylaxis) without the involvement of IgE. (lecturio.com)