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 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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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).
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 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.
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).
A serine endopeptidase that has specificity for cleavage at ARGININE. It cleaves a variety of prohormones including PRO-OPIOMELANOCORTIN, proluteinizing-hormone-releasing hormone, proenkephalins, prodynorphin, and PROINSULIN.
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.
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).
A CALCIUM-dependent endopeptidase that has specificity for cleavage at ARGININE that is near paired basic residues. It cleaves a variety of prohormones including PRO-OPIOMELANOCORTIN; PRORENIN; proenkephalins; prodynorphin; prosomatostatin; and PROINSULIN.
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.
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.
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.
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.
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).
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).
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.
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.
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.
Molecules on the surface of some B-lymphocytes and macrophages, that recognize and combine with the C3b, C3d, C1q, and C4b components of complement.
A serine endopeptidase found primarily in the EXTRACELLULAR MATRIX. It has specificity for cleavage of a variety of substrates including PRORENIN, pro-membrane type-1 matrix metalloproteinase, and NEURAL CELL ADHESION MOLECULE L1.
Proteolytic enzymes that are involved in the conversion of protein precursors such as peptide prohormones into PEPTIDE HORMONES. Some are ENDOPEPTIDASES, some are EXOPEPTIDASES.
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.
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).
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.
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.
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.
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.
An IgG autoantibody against the ALTERNATIVE PATHWAY C3 CONVERTASE, found in serum of patients with MESANGIOCAPILLARY GLOMERULONEPHRITIS. The binding of this autoantibody to C3bBb stabilizes the enzyme thus reduces the actions of C3b inactivators (COMPLEMENT FACTOR H; COMPLEMENT FACTOR I). This abnormally stabilized enzyme induces a continuous COMPLEMENT ACTIVATION and generation of C3b thereby promoting the assembly of MEMBRANE ATTACK COMPLEX and cytolysis.
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.
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.
A family of SERINE ENDOPEPTIDASES isolated from Bacillus subtilis. EC 3.4.21.-
A proprotein convertase with specificity for the proproteins of PROALBUMIN; COMPLEMENT 3C; and VON WILLEBRAND FACTOR. It has specificity for cleavage near paired ARGININE residues that are separated by two amino acids.
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.
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.
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).
A process whereby multiple RNA transcripts are generated from a single gene. Alternative splicing involves the splicing together of other possible sets of EXONS during the processing of some, but not all, transcripts of the gene. Thus a particular exon may be connected to any one of several alternative exons to form a mature RNA. The alternative forms of mature MESSENGER RNA produce PROTEIN ISOFORMS in which one part of the isoforms is common while the other parts are different.
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.
Important enzymes in the ALTERNATIVE COMPLEMENT ACTIVATION PATHWAY. They cleave COMPLEMENT C3 and COMPLEMENT C5.
Compounds that negatively regulate the cascade process of COMPLEMENT ACTIVATION. Uncontrolled complement activation and resulting cell lysis is potentially dangerous for the host.
The destruction of ERYTHROCYTES by many different causal agents such as antibodies, bacteria, chemicals, temperature, and changes in tonicity.
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.
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.
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.
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.
A G-protein-coupled receptor that signals an increase in intracellular calcium in response to the potent ANAPHYLATOXIN peptide COMPLEMENT C5A.
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).
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.
The N-terminal fragment of COMPLEMENT 2, released by the action of activated COMPLEMENT C1S.
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.
Serum proteins that inhibit, antagonize, or inactivate COMPLEMENT C1 or its subunits.
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).
Any member of the group of ENDOPEPTIDASES containing at the active site a serine residue involved in catalysis.
An acidic protein found in the NEUROENDOCRINE SYSTEM that functions as a molecular chaperone for PROPROTEIN CONVERTASE 2.
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.
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.
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.
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.
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.
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 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.
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.
A ZINC-containing exopeptidase primarily found in SECRETORY VESICLES of endocrine and neuroendocrine cells. It catalyzes the cleavage of C-terminal ARGININE or LYSINE residues from polypeptides and is active in processing precursors of PEPTIDE HORMONES and other bioactive peptides.
The major immunoglobulin isotype class in normal human serum. There are several isotype subclasses of IgG, for example, IgG1, IgG2A, and IgG2B.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
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.
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.
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.
Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.
The engulfing and degradation of microorganisms; other cells that are dead, dying, or pathogenic; and foreign particles by phagocytic cells (PHAGOCYTES).
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.
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.
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.
Established cell cultures that have the potential to propagate indefinitely.
Important enzymes in the CLASSICAL COMPLEMENT ACTIVATION PATHWAY. They cleave COMPLEMENT C3 and COMPLEMENT C5.
The rate dynamics in chemical or physical systems.
Physiologically inactive substances that can be converted to active enzymes.
Proteins prepared by recombinant DNA technology.
Proteins that are present in blood serum, including SERUM ALBUMIN; BLOOD COAGULATION FACTORS; and many other types of proteins.
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.
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.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
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.
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.
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.
Any of various enzymatically catalyzed post-translational modifications of PEPTIDES or PROTEINS in the cell of origin. These modifications include carboxylation; HYDROXYLATION; ACETYLATION; PHOSPHORYLATION; METHYLATION; GLYCOSYLATION; ubiquitination; oxidation; proteolysis; and crosslinking and result in changes in molecular weight and electrophoretic motility.
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.
Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.
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).
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.
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.
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.
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.
Antibodies produced by a single clone of cells.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.
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.
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.
The clear portion of BLOOD that is left after BLOOD COAGULATION to remove BLOOD CELLS and clotting proteins.
A syndrome that is associated with microvascular diseases of the KIDNEY, such as RENAL CORTICAL NECROSIS. It is characterized by hemolytic anemia (ANEMIA, HEMOLYTIC); THROMBOCYTOPENIA; and ACUTE RENAL FAILURE.
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.
Elements of limited time intervals, contributing to particular results or situations.
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.
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.
A chelating agent that sequesters a variety of polyvalent cations such as CALCIUM. It is used in pharmaceutical manufacturing and as a food additive.
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.
A cluster of convoluted capillaries beginning at each nephric tubule in the kidney and held together by connective tissue.
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
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.
A sub-subclass of endopeptidases that depend on an ASPARTIC ACID residue for their activity.
Hormones secreted by the PITUITARY GLAND including those from the anterior lobe (adenohypophysis), the posterior lobe (neurohypophysis), and the ill-defined intermediate lobe. Structurally, they include small peptides, proteins, and glycoproteins. They are under the regulation of neural signals (NEUROTRANSMITTERS) or neuroendocrine signals (HYPOTHALAMIC HORMONES) from the hypothalamus as well as feedback from their targets such as ADRENAL CORTEX HORMONES; ANDROGENS; ESTROGENS.
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.
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.
The common precursor polypeptide of pancreatic GLUCAGON and intestinal GLUCAGON-LIKE PEPTIDES. Proglucagon is the 158-amino acid segment of preproglucagon without the N-terminal signal sequence. Proglucagon is expressed in the PANCREAS; INTESTINES; and the CENTRAL NERVOUS SYSTEM. Posttranslational processing of proglucagon is tissue-specific yielding numerous bioactive peptides.
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.
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.
The parts of a transcript of a split GENE remaining after the INTRONS are removed. They are spliced together to become a MESSENGER RNA or other functional RNA.
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.
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).
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.
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.
Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.
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.
A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.
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.
A 30-kDa protein synthesized primarily in the ANTERIOR PITUITARY GLAND and the HYPOTHALAMUS. It is also found in the skin and other peripheral tissues. Depending on species and tissues, POMC is cleaved by PROHORMONE CONVERTASES yielding various active peptides including ACTH; BETA-LIPOTROPIN; ENDORPHINS; MELANOCYTE-STIMULATING HORMONES; and others (GAMMA-LPH; CORTICOTROPIN-LIKE INTERMEDIATE LOBE PEPTIDE; N-terminal peptide of POMC or NPP).
Transport proteins that carry specific substances in the blood or across cell membranes.
The sum of the weight of all the atoms in a molecule.
A specific immune response elicited by a specific dose of an immunologically active substance or cell in an organism, tissue, or cell.
CELL LINE derived from the ovary of the Chinese hamster, Cricetulus griseus (CRICETULUS). The species is a favorite for cytogenetic studies because of its small chromosome number. The cell line has provided model systems for the study of genetic alterations in cultured mammalian cells.
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.)
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).
The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
Proteins found in any species of bacterium.
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.
Single-stranded complementary DNA synthesized from an RNA template by the action of RNA-dependent DNA polymerase. cDNA (i.e., complementary DNA, not circular DNA, not C-DNA) is used in a variety of molecular cloning experiments as well as serving as a specific hybridization probe.
Glycoproteins found on the membrane or surface of cells.
Polysaccharides consisting of mannose units.
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.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.
Immunoelectrophoresis in which a second electrophoretic transport is performed on the initially separated antigen fragments into an antibody-containing medium in a direction perpendicular to the first electrophoresis.
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).
A chelating agent relatively more specific for calcium and less toxic than EDETIC ACID.
Inflammation of any part of the KIDNEY.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
Histochemical localization of immunoreactive substances using labeled antibodies as reagents.
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.
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.
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)
A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.
Serum proteins with an electrophoretic mobility that falls between ALPHA-GLOBULINS and GAMMA-GLOBULINS.
A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.
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.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
Antibodies that react with self-antigens (AUTOANTIGENS) of the organism that produced them.
Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.
ENDOPEPTIDASES which use a metal such as ZINC in the catalytic mechanism.
The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.
The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.
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.
The class of all enzymes catalyzing oxidoreduction reactions. The substrate that is oxidized is regarded as a hydrogen donor. The systematic name is based on donor:acceptor oxidoreductase. The recommended name will be dehydrogenase, wherever this is possible; as an alternative, reductase can be used. Oxidase is only used in cases where O2 is the acceptor. (Enzyme Nomenclature, 1992, p9)
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.
Detection of RNA that has been electrophoretically separated and immobilized by blotting on nitrocellulose or other type of paper or nylon membrane followed by hybridization with labeled NUCLEIC ACID PROBES.
A component of NF-kappa B transcription factor. It is proteolytically processed from NF-kappa B p100 precursor protein and is important for maturation of B-LYMPHOCYTES and adaptive HUMORAL IMMUNITY.
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.
Variant forms of the same gene, occupying the same locus on homologous CHROMOSOMES, and governing the variants in production of the same gene product.
A subclass of PEPTIDE HYDROLASES that catalyze the internal cleavage of PEPTIDES or PROTEINS.
The process of cleaving a chemical compound by the addition of a molecule of water.
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.
Enzymes that act at a free C-terminus of a polypeptide to liberate a single amino acid residue.
Polysaccharide isolated from the edible mushroom LENTINULA EDODES. The exact composition is unknown.
Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.
A 69-amino acid peptide derived from the N-terminal of PROGLUCAGON. It is mainly produced by the INTESTINAL L CELLS. Further processing of glicentin yield a 30-amino acid N-terminal peptide (glicentin-related polypeptide) and a 37-amino acid peptide OXYNTOMODULIN. Both glicentin and oxyntomodulin can reduce digestive secretions and delay gastric emptying.
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.
Procedures, such as TISSUE CULTURE TECHNIQUES; mathematical models; etc., when used or advocated for use in place of the use of animals in research or diagnostic laboratories.
A serine endopeptidase isolated from Bacillus subtilis. It hydrolyzes proteins with broad specificity for peptide bonds, and a preference for a large uncharged residue in P1. It also hydrolyzes peptide amides. (From Enzyme Nomenclature, 1992) EC 3.4.21.62.
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
The relationship between the dose of an administered drug and the response of the organism to the drug.
A group of naturally occurring N-and O-acyl derivatives of the deoxyamino sugar neuraminic acid. They are ubiquitously distributed in many tissues.
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.
A metallic element that has the atomic symbol Mg, atomic number 12, and atomic weight 24.31. It is important for the activity of many enzymes, especially those involved in OXIDATIVE PHOSPHORYLATION.
A species of motile, free-living, gram-negative bacteria that occur in the soil. They are aerobic or microaerophilic and are sometimes capable of nitrogen fixation.
Thickening of the walls of small ARTERIES or ARTERIOLES due to cell proliferation or HYALINE deposition.
A highly acidic mucopolysaccharide formed of equal parts of sulfated D-glucosamine and D-glucuronic acid with sulfaminic bridges. The molecular weight ranges from six to twenty thousand. Heparin occurs in and is obtained from liver, lung, mast cells, etc., of vertebrates. Its function is unknown, but it is used to prevent blood clotting in vivo and vitro, in the form of many different salts.
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.
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.

Structural and functional analysis of a C3b-specific antibody that selectively inhibits the alternative pathway of complement. (1/1)

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There are two main types of hemolysis:

1. Intravascular hemolysis: This type occurs within the blood vessels and is caused by factors such as mechanical injury, oxidative stress, and certain infections.
2. Extravascular hemolysis: This type occurs outside the blood vessels and is caused by factors such as bone marrow disorders, splenic rupture, and certain medications.

Hemolytic anemia is a condition that occurs when there is excessive hemolysis of RBCs, leading to a decrease in the number of healthy red blood cells in the body. This can cause symptoms such as fatigue, weakness, pale skin, and shortness of breath.

Some common causes of hemolysis include:

1. Genetic disorders such as sickle cell anemia and thalassemia.
2. Autoimmune disorders such as autoimmune hemolytic anemia (AIHA).
3. Infections such as malaria, babesiosis, and toxoplasmosis.
4. Medications such as antibiotics, nonsteroidal anti-inflammatory drugs (NSAIDs), and blood thinners.
5. Bone marrow disorders such as aplastic anemia and myelofibrosis.
6. Splenic rupture or surgical removal of the spleen.
7. Mechanical injury to the blood vessels.

Diagnosis of hemolysis is based on a combination of physical examination, medical history, and laboratory tests such as complete blood count (CBC), blood smear examination, and direct Coombs test. Treatment depends on the underlying cause and may include supportive care, blood transfusions, and medications to suppress the immune system or prevent infection.

Idiopathic membranous nephropathy (IMN) is an autoimmune disorder that causes GNM without any identifiable cause. Secondary membranous nephropathy, on the other hand, is caused by systemic diseases such as lupus or cancer.

The symptoms of GNM can vary depending on the severity of the disease and may include blood in the urine, proteinuria, edema, high blood pressure, and decreased kidney function. The diagnosis of GNM is based on a combination of clinical findings, laboratory tests, and renal biopsy.

Treatment for GNM is aimed at slowing the progression of the disease and managing symptoms. Medications such as corticosteroids, immunosuppressive drugs, and blood pressure-lowering drugs may be used to treat GNM. In some cases, kidney transplantation may be necessary.

The prognosis for GNM varies depending on the severity of the disease and the underlying cause. In general, the prognosis for IMN is better than for secondary membranous nephropathy. With proper treatment, some patients with GNM can experience a slowing or stabilization of the disease, while others may progress to end-stage renal disease (ESRD).

The cause of GNM is not fully understood, but it is believed to be an autoimmune disorder that leads to inflammation and damage to the glomerular membrane. Genetic factors and environmental triggers may also play a role in the development of GNM.

There are several risk factors for developing GNM, including family history, age (GMN is more common in adults), and certain medical conditions such as hypertension and diabetes.

The main complications of GNM include:

1. ESRD: Progression to ESRD is a common outcome of untreated GNM.
2. High blood pressure: GNM can lead to high blood pressure, which can further damage the kidneys.
3. Infections: GNM increases the risk of infections due to impaired immune function.
4. Kidney failure: GNM can cause chronic kidney failure, leading to the need for dialysis or a kidney transplant.
5. Cardiovascular disease: GNM is associated with an increased risk of cardiovascular disease, including heart attack and stroke.
6. Malnutrition: GNM can lead to malnutrition due to decreased appetite, nausea, and vomiting.
7. Bone disease: GNM can cause bone disease, including osteoporosis and bone pain.
8. Anemia: GNM can cause anemia, which can lead to fatigue, weakness, and shortness of breath.
9. Increased risk of infections: GNM increases the risk of infections due to impaired immune function.
10. Decreased quality of life: GNM can significantly decrease a person's quality of life, leading to decreased mobility, pain, and discomfort.

It is important for individuals with GNM to receive early diagnosis and appropriate treatment to prevent or delay the progression of these complications.

The symptoms of glomerulonephritis can vary depending on the underlying cause of the disease, but may include:

* Blood in the urine (hematuria)
* Proteinuria (excess protein in the urine)
* Reduced kidney function
* Swelling in the legs and ankles (edema)
* High blood pressure

Glomerulonephritis can be caused by a variety of factors, including:

* Infections such as staphylococcal or streptococcal infections
* Autoimmune disorders such as lupus or rheumatoid arthritis
* Allergic reactions to certain medications
* Genetic defects
* Certain diseases such as diabetes, high blood pressure, and sickle cell anemia

The diagnosis of glomerulonephritis typically involves a physical examination, medical history, and laboratory tests such as urinalysis, blood tests, and kidney biopsy.

Treatment for glomerulonephritis depends on the underlying cause of the disease and may include:

* Antibiotics to treat infections
* Medications to reduce inflammation and swelling
* Diuretics to reduce fluid buildup in the body
* Immunosuppressive medications to suppress the immune system in cases of autoimmune disorders
* Dialysis in severe cases

The prognosis for glomerulonephritis depends on the underlying cause of the disease and the severity of the inflammation. In some cases, the disease may progress to end-stage renal disease, which requires dialysis or a kidney transplant. With proper treatment, however, many people with glomerulonephritis can experience a good outcome and maintain their kidney function over time.

The term "systemic" refers to the fact that the disease affects multiple organ systems, including the skin, joints, kidneys, lungs, and nervous system. LES is a complex condition, and its symptoms can vary widely depending on which organs are affected. Common symptoms include fatigue, fever, joint pain, rashes, and swelling in the extremities.

There are several subtypes of LES, including:

1. Systemic lupus erythematosus (SLE): This is the most common form of the disease, and it can affect anyone, regardless of age or gender.
2. Discoid lupus erythematosus (DLE): This subtype typically affects the skin, causing a red, scaly rash that does not go away.
3. Drug-induced lupus erythematosus: This form of the disease is caused by certain medications, and it usually resolves once the medication is stopped.
4. Neonatal lupus erythematosus: This rare condition affects newborn babies of mothers with SLE, and it can cause liver and heart problems.

There is no cure for LES, but treatment options are available to manage the symptoms and prevent flares. Treatment may include nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids, immunosuppressive medications, and antimalarial drugs. In severe cases, hospitalization may be necessary to monitor and treat the disease.

It is important for people with LES to work closely with their healthcare providers to manage their condition and prevent complications. With proper treatment and self-care, many people with LES can lead active and fulfilling lives.

The disorder is caused by mutations in the HBB gene that codes for the beta-globin subunit of hemoglobin. These mutations result in the production of abnormal hemoglobins that are unstable and prone to breakdown, leading to the release of free hemoglobin into the urine.

HP is classified into two types based on the severity of symptoms:

1. Type 1 HP: This is the most common form of the disorder and is characterized by mild to moderate anemia, occasional hemoglobinuria, and a normal life expectancy.
2. Type 2 HP: This is a more severe form of the disorder and is characterized by severe anemia, recurrent hemoglobinuria, and a shorter life expectancy.

There is no cure for HP, but treatment options are available to manage symptoms and prevent complications. These may include blood transfusions, folic acid supplements, and medications to reduce the frequency and severity of hemoglobinuria episodes.

The symptoms of HUS include:

* Diarrhea
* Vomiting
* Abdominal pain
* Fatigue
* Weakness
* Shortness of breath
* Pale or yellowish skin
* Easy bruising or bleeding

If you suspect that someone has HUS, it is important to seek medical attention immediately. A healthcare provider will perform a physical examination and order blood tests to diagnose the condition. Treatment for HUS typically involves addressing the underlying cause of the condition, such as stopping certain medications or treating an infection. In some cases, hospitalization may be necessary to manage complications such as kidney failure.

Preventative measures to reduce the risk of developing HUS include:

* Practicing good hygiene, especially during outbreaks of diarrheal illnesses
* Avoiding certain medications that are known to increase the risk of HUS
* Maintaining a healthy diet and staying hydrated
* Managing any underlying medical conditions such as high blood pressure or diabetes.

1) They share similarities with humans: Many animal species share similar biological and physiological characteristics with humans, making them useful for studying human diseases. For example, mice and rats are often used to study diseases such as diabetes, heart disease, and cancer because they have similar metabolic and cardiovascular systems to humans.

2) They can be genetically manipulated: Animal disease models can be genetically engineered to develop specific diseases or to model human genetic disorders. This allows researchers to study the progression of the disease and test potential treatments in a controlled environment.

3) They can be used to test drugs and therapies: Before new drugs or therapies are tested in humans, they are often first tested in animal models of disease. This allows researchers to assess the safety and efficacy of the treatment before moving on to human clinical trials.

4) They can provide insights into disease mechanisms: Studying disease models in animals can provide valuable insights into the underlying mechanisms of a particular disease. This information can then be used to develop new treatments or improve existing ones.

5) Reduces the need for human testing: Using animal disease models reduces the need for human testing, which can be time-consuming, expensive, and ethically challenging. However, it is important to note that animal models are not perfect substitutes for human subjects, and results obtained from animal studies may not always translate to humans.

6) They can be used to study infectious diseases: Animal disease models can be used to study infectious diseases such as HIV, TB, and malaria. These models allow researchers to understand how the disease is transmitted, how it progresses, and how it responds to treatment.

7) They can be used to study complex diseases: Animal disease models can be used to study complex diseases such as cancer, diabetes, and heart disease. These models allow researchers to understand the underlying mechanisms of the disease and test potential treatments.

8) They are cost-effective: Animal disease models are often less expensive than human clinical trials, making them a cost-effective way to conduct research.

9) They can be used to study drug delivery: Animal disease models can be used to study drug delivery and pharmacokinetics, which is important for developing new drugs and drug delivery systems.

10) They can be used to study aging: Animal disease models can be used to study the aging process and age-related diseases such as Alzheimer's and Parkinson's. This allows researchers to understand how aging contributes to disease and develop potential treatments.

Nephritis is often diagnosed through a combination of physical examination, medical history, and laboratory tests such as urinalysis and blood tests. Treatment for nephritis depends on the underlying cause, but may include antibiotics, corticosteroids, and immunosuppressive medications. In severe cases, dialysis may be necessary to remove waste products from the blood.

Some common types of nephritis include:

1. Acute pyelonephritis: This is a type of bacterial infection that affects the kidneys and can cause sudden and severe symptoms.
2. Chronic pyelonephritis: This is a type of inflammation that occurs over a longer period of time, often as a result of recurrent infections or other underlying conditions.
3. Lupus nephritis: This is a type of inflammation that occurs in people with systemic lupus erythematosus (SLE), an autoimmune disorder that can affect multiple organs.
4. IgA nephropathy: This is a type of inflammation that occurs when an antibody called immunoglobulin A (IgA) deposits in the kidneys and causes damage.
5. Mesangial proliferative glomerulonephritis: This is a type of inflammation that affects the mesangium, a layer of tissue in the kidney that helps to filter waste products from the blood.
6. Minimal change disease: This is a type of nephrotic syndrome (a group of symptoms that include proteinuria, or excess protein in the urine) that is caused by inflammation and changes in the glomeruli, the tiny blood vessels in the kidneys that filter waste products from the blood.
7. Membranous nephropathy: This is a type of inflammation that occurs when there is an abnormal buildup of antibodies called immunoglobulin G (IgG) in the glomeruli, leading to damage to the kidneys.
8. Focal segmental glomerulosclerosis: This is a type of inflammation that affects one or more segments of the glomeruli, leading to scarring and loss of function.
9. Post-infectious glomerulonephritis: This is a type of inflammation that occurs after an infection, such as streptococcal infections, and can cause damage to the kidneys.
10. Acute tubular necrosis (ATN): This is a type of inflammation that occurs when there is a sudden loss of blood flow to the kidneys, causing damage to the tubules, which are tiny tubes in the kidneys that help to filter waste products from the blood.

There are several key features of inflammation:

1. Increased blood flow: Blood vessels in the affected area dilate, allowing more blood to flow into the tissue and bringing with it immune cells, nutrients, and other signaling molecules.
2. Leukocyte migration: White blood cells, such as neutrophils and monocytes, migrate towards the site of inflammation in response to chemical signals.
3. Release of mediators: Inflammatory mediators, such as cytokines and chemokines, are released by immune cells and other cells in the affected tissue. These molecules help to coordinate the immune response and attract more immune cells to the site of inflammation.
4. Activation of immune cells: Immune cells, such as macrophages and T cells, become activated and start to phagocytose (engulf) pathogens or damaged tissue.
5. Increased heat production: Inflammation can cause an increase in metabolic activity in the affected tissue, leading to increased heat production.
6. Redness and swelling: Increased blood flow and leakiness of blood vessels can cause redness and swelling in the affected area.
7. Pain: Inflammation can cause pain through the activation of nociceptors (pain-sensing neurons) and the release of pro-inflammatory mediators.

Inflammation can be acute or chronic. Acute inflammation is a short-term response to injury or infection, which helps to resolve the issue quickly. Chronic inflammation is a long-term response that can cause ongoing damage and diseases such as arthritis, asthma, and cancer.

There are several types of inflammation, including:

1. Acute inflammation: A short-term response to injury or infection.
2. Chronic inflammation: A long-term response that can cause ongoing damage and diseases.
3. Autoimmune inflammation: An inappropriate immune response against the body's own tissues.
4. Allergic inflammation: An immune response to a harmless substance, such as pollen or dust mites.
5. Parasitic inflammation: An immune response to parasites, such as worms or fungi.
6. Bacterial inflammation: An immune response to bacteria.
7. Viral inflammation: An immune response to viruses.
8. Fungal inflammation: An immune response to fungi.

There are several ways to reduce inflammation, including:

1. Medications such as nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids, and disease-modifying anti-rheumatic drugs (DMARDs).
2. Lifestyle changes, such as a healthy diet, regular exercise, stress management, and getting enough sleep.
3. Alternative therapies, such as acupuncture, herbal supplements, and mind-body practices.
4. Addressing underlying conditions, such as hormonal imbalances, gut health issues, and chronic infections.
5. Using anti-inflammatory compounds found in certain foods, such as omega-3 fatty acids, turmeric, and ginger.

It's important to note that chronic inflammation can lead to a range of health problems, including:

1. Arthritis
2. Diabetes
3. Heart disease
4. Cancer
5. Alzheimer's disease
6. Parkinson's disease
7. Autoimmune disorders, such as lupus and rheumatoid arthritis.

Therefore, it's important to manage inflammation effectively to prevent these complications and improve overall health and well-being.

There are two main types of MD:

1. Dry Macular Degeneration (DMD): This is the most common form of MD, accounting for about 90% of cases. It is caused by the gradual accumulation of waste material in the macula, which can lead to cell death and vision loss over time.
2. Wet Macular Degeneration (WMD): This type of MD is less common but more aggressive, accounting for about 10% of cases. It occurs when new blood vessels grow underneath the retina, leaking fluid and causing damage to the macula. This can lead to rapid vision loss if left untreated.

The symptoms of MD can vary depending on the severity and type of the condition. Common symptoms include:

* Blurred vision
* Distorted vision (e.g., straight lines appearing wavy)
* Difficulty reading or recognizing faces
* Difficulty adjusting to bright light
* Blind spots in central vision

MD can have a significant impact on daily life, making it difficult to perform everyday tasks such as driving, reading, and recognizing faces.

There is currently no cure for MD, but there are several treatment options available to slow down the progression of the disease and manage its symptoms. These include:

* Anti-vascular endothelial growth factor (VEGF) injections: These medications can help prevent the growth of new blood vessels and reduce inflammation in the macula.
* Photodynamic therapy: This involves the use of a light-sensitive drug and low-intensity laser to damage and shrink the abnormal blood vessels in the macula.
* Vitamin supplements: Certain vitamins, such as vitamin C, E, and beta-carotene, have been shown to slow down the progression of MD.
* Laser surgery: This can be used to reduce the number of abnormal blood vessels in the macula and improve vision.

It is important for individuals with MD to receive regular monitoring and treatment from an eye care professional to manage their condition and prevent complications.

Arteriolosclerosis is often associated with conditions such as hypertension, diabetes, and atherosclerosis, which is the buildup of plaque in the arteries. It can also be caused by other factors such as smoking, high cholesterol levels, and inflammation.

The symptoms of arteriolosclerosis can vary depending on the location and severity of the condition, but may include:

* Decreased blood flow to organs or tissues
* Fatigue
* Weakness
* Shortness of breath
* Dizziness or lightheadedness
* Pain in the affected limbs or organs

Arteriolosclerosis is typically diagnosed through a combination of physical examination, medical history, and diagnostic tests such as ultrasound, angiography, or blood tests. Treatment for the condition may include lifestyle changes such as exercise and dietary modifications, medications to control risk factors such as hypertension and high cholesterol, and in some cases, surgical intervention to open or bypass blocked arterioles.

In summary, arteriolosclerosis is a condition where the arterioles become narrowed or obstructed, leading to decreased blood flow to organs and tissues and potentially causing a range of health problems. It is often associated with other conditions such as hypertension and atherosclerosis, and can be diagnosed through a combination of physical examination, medical history, and diagnostic tests. Treatment may include lifestyle changes and medications to control risk factors, as well as surgical intervention in some cases.

People with agammaglobulinemia are more susceptible to infections, particularly those caused by encapsulated bacteria, such as Streptococcus pneumoniae and Haemophilus influenzae type b. They may also experience recurrent sinopulmonary infections, ear infections, and gastrointestinal infections. The disorder can be managed with intravenous immunoglobulin (IVIG) therapy, which provides antibodies to help prevent infections. In severe cases, a bone marrow transplant may be necessary.

Agammaglobulinemia is an autosomal recessive disorder, meaning that a person must inherit two mutated copies of the BTK gene (one from each parent) to develop the condition. It is relatively rare, affecting approximately one in 1 million people worldwide. The disorder can be diagnosed through genetic testing and a complete blood count (CBC) that shows low levels of immunoglobulins.

Treatment for ag

There are several types of lupus nephritis, each with its own unique characteristics and symptoms. The most common forms include:

* Class I (mesangial proliferative glomerulonephritis): This type is characterized by the growth of abnormal cells in the glomeruli (blood-filtering units of the kidneys).
* Class II (active lupus nephritis): This type is characterized by widespread inflammation and damage to the kidneys, with or without the presence of antibodies.
* Class III (focal lupus nephritis): This type is characterized by localized inflammation in certain areas of the kidneys.
* Class IV (lupus nephritis with crescentic glomerulonephritis): This type is characterized by widespread inflammation and damage to the kidneys, with crescent-shaped tissue growth in the glomeruli.
* Class V (lupus nephritis with sclerotic changes): This type is characterized by hardening and shrinkage of the glomeruli due to scarring.

Lupus Nephritis can cause a range of symptoms, including:

* Proteinuria (excess protein in the urine)
* Hematuria (blood in the urine)
* Reduced kidney function
* Swelling (edema)
* Fatigue
* Fever
* Joint pain

Lupus Nephritis can be diagnosed through a combination of physical examination, medical history, laboratory tests, and kidney biopsy. Treatment options for lupus nephritis include medications to suppress the immune system, control inflammation, and prevent further damage to the kidneys. In severe cases, dialysis or a kidney transplant may be necessary.

The most common form of this disease is Meningococcal Group B (MenB). Symptoms often develop within hours or days after exposure, but can be nonspecific, such as fever, headache, and muscle aches.

Early signs that are more specific and suggestive of the diagnosis include neck stiffness, confusion, seizures, and rash. Diagnosis is by culture or PCR of a sterile site. Treatment consists of antibiotics that cover Neisseria meningitidis, which should be initiated promptly after recognition of the signs and symptoms.

Prevention with vaccines is recommended for infants at 2 months of age; boosters are given at 4 months, 6 months, and 12 to 15 months of age.

There are three main forms of ACH:

1. Classic congenital adrenal hyperplasia (CAH): This is the most common form of ACH, accounting for about 90% of cases. It is caused by mutations in the CYP21 gene, which codes for an enzyme that converts cholesterol into cortisol and aldosterone.
2. Non-classic CAH (NCAH): This form of ACH is less common than classic CAH and is caused by mutations in other genes involved in cortisol and aldosterone production.
3. Mineralocorticoid excess (MOE) or glucocorticoid deficiency (GD): These are rare forms of ACH that are characterized by excessive production of mineralocorticoids (such as aldosterone) or a deficiency of glucocorticoids (such as cortisol).

The symptoms of ACH can vary depending on the specific form of the disorder and the age at which it is diagnosed. In classic CAH, symptoms typically appear in infancy and may include:

* Premature puberty (in girls) or delayed puberty (in boys)
* Abnormal growth patterns
* Distended abdomen
* Fatigue
* Weight gain or obesity
* Easy bruising or bleeding

In NCAH and MOE/GD, symptoms may be less severe or may not appear until later in childhood or adulthood. They may include:

* High blood pressure
* Low blood sugar (hypoglycemia)
* Weight gain or obesity
* Fatigue
* Mood changes

If left untreated, ACH can lead to serious complications, including:

* Adrenal gland insufficiency
* Heart problems
* Bone health problems
* Increased risk of infections
* Mental health issues (such as depression or anxiety)

Treatment for ACH typically involves hormone replacement therapy to restore the balance of hormones in the body. This may involve taking medications such as cortisol, aldosterone, or other hormones to replace those that are deficient or imbalanced. In some cases, surgery may be necessary to remove an adrenal tumor or to correct physical abnormalities.

With proper treatment, many individuals with ACH can lead healthy, active lives. However, it is important for individuals with ACH to work closely with their healthcare providers to manage their condition and prevent complications. This may involve regular check-ups, hormone level monitoring, and lifestyle changes such as a healthy diet and regular exercise.

Symptoms of meningococcal meningitis typically develop within 3-7 days after exposure and may include fever, headache, stiff neck, confusion, nausea and vomiting, sensitivity to light, and seizures. In severe cases, the infection can lead to shock, organ failure, and death within hours of the onset of symptoms.

Diagnosis is typically made by a combination of physical examination, laboratory tests (such as blood cultures and PCR), and imaging studies (such as CT or MRI scans). Treatment typically involves antibiotics, intravenous fluids, and supportive care to manage fever, pain, and other symptoms. In severe cases, hospitalization in an intensive care unit may be necessary.

Prevention of meningococcal meningitis includes the use of vaccines, good hygiene practices (such as frequent handwashing), and avoidance of close contact with people who are sick. A vaccine is available for children and teens, and some colleges and universities require students to be vaccinated before moving into dorms.

Early diagnosis and treatment are crucial in preventing long-term complications and reducing the risk of death from meningococcal meningitis. If you suspect that you or someone else may have meningococcal meningitis, it is important to seek medical attention immediately.

Lipodystrophy can be caused by genetic mutations, hormonal imbalances, or certain medications. It can also be associated with other medical conditions such as metabolic disorders, endocrine problems, and neurological diseases.

The symptoms of lipodystrophy can vary depending on the type and severity of the condition. Common symptoms include:

1. Muscle wasting and weakness
2. Fat redistribution to certain areas of the body (such as the face, neck, and torso)
3. Metabolic problems such as insulin resistance and high blood sugar
4. Hormonal imbalances
5. Abnormal body shape and proportions
6. Poor wound healing
7. Easy bruising and bleeding
8. Increased risk of infections
9. Joint pain and stiffness
10. Mood changes such as depression, anxiety, and irritability

Treatment for lipodystrophy depends on the underlying cause of the condition. Medications, lifestyle modifications, and surgery may be used to manage symptoms and improve quality of life. In some cases, lipodystrophy can be a sign of an underlying medical condition that needs to be treated.

Lipodystrophy can have a significant impact on an individual's quality of life, affecting their physical appearance, self-esteem, and ability to perform daily activities. It is important to seek medical attention if symptoms persist or worsen over time. With proper diagnosis and treatment, individuals with lipodystrophy can improve their symptoms and overall health.

These animal models allow researchers to study the underlying causes of arthritis, test new treatments and therapies, and evaluate their effectiveness in a controlled environment before moving to human clinical trials. Experimental arthritis models are used to investigate various aspects of the disease, including its pathophysiology, immunogenicity, and potential therapeutic targets.

Some common experimental arthritis models include:

1. Collagen-induced arthritis (CIA): This model is induced in mice by immunizing them with type II collagen, which leads to an autoimmune response and inflammation in the joints.
2. Rheumatoid arthritis (RA) models: These models are developed by transferring cells from RA patients into immunodeficient mice, which then develop arthritis-like symptoms.
3. Osteoarthritis (OA) models: These models are induced in animals by subjecting them to joint injury or overuse, which leads to degenerative changes in the joints and bone.
4. Psoriatic arthritis (PsA) models: These models are developed by inducing psoriasis in mice, which then develop arthritis-like symptoms.

Experimental arthritis models have contributed significantly to our understanding of the disease and have helped to identify potential therapeutic targets for the treatment of arthritis. However, it is important to note that these models are not perfect representations of human arthritis and should be used as tools to complement, rather than replace, human clinical trials.

The condition is caused by mutations in the genes that code for proteins involved in cholesterol transport and metabolism, such as the low-density lipoprotein receptor gene (LDLR) or the PCSK9 gene. These mutations lead to a decrease in the ability of the liver to remove excess cholesterol from the bloodstream, resulting in high levels of LDL cholesterol and low levels of HDL cholesterol.

Hyperlipoproteinemia type II is usually inherited in an autosomal dominant pattern, meaning that a single copy of the mutated gene is enough to cause the condition. However, some cases can be caused by spontaneous mutations or incomplete penetrance, where not all individuals with the mutated gene develop the condition.

Symptoms of hyperlipoproteinemia type II can include xanthomas (yellowish deposits of cholesterol in the skin), corneal arcus (a white, waxy deposit on the iris of the eye), and tendon xanthomas (small, soft deposits of cholesterol under the skin). Treatment typically involves a combination of dietary changes and medication to lower LDL cholesterol levels and increase HDL cholesterol levels. In severe cases, liver transplantation may be necessary.

Hyperlipoproteinemia type II is a serious condition that can lead to cardiovascular disease, including heart attacks, strokes, and peripheral artery disease. Early diagnosis and treatment are important to prevent or delay the progression of the disease and reduce the risk of complications.

Proteinuria is usually diagnosed by a urine protein-to-creatinine ratio (P/C ratio) or a 24-hour urine protein collection. The amount and duration of proteinuria can help distinguish between different underlying causes and predict prognosis.

Proteinuria can have significant clinical implications, as it is associated with increased risk of cardiovascular disease, kidney damage, and malnutrition. Treatment of the underlying cause can help reduce or eliminate proteinuria.

Reperfusion injury can cause inflammation, cell death, and impaired function in the affected tissue or organ. The severity of reperfusion injury can vary depending on the duration and severity of the initial ischemic event, as well as the promptness and effectiveness of treatment to restore blood flow.

Reperfusion injury can be a complicating factor in various medical conditions, including:

1. Myocardial infarction (heart attack): Reperfusion injury can occur when blood flow is restored to the heart muscle after a heart attack, leading to inflammation and cell death.
2. Stroke: Reperfusion injury can occur when blood flow is restored to the brain after an ischemic stroke, leading to inflammation and damage to brain tissue.
3. Organ transplantation: Reperfusion injury can occur when a transplanted organ is subjected to ischemia during harvesting or preservation, and then reperfused with blood.
4. Peripheral arterial disease: Reperfusion injury can occur when blood flow is restored to a previously occluded peripheral artery, leading to inflammation and damage to the affected tissue.

Treatment of reperfusion injury often involves medications to reduce inflammation and oxidative stress, as well as supportive care to manage symptoms and prevent further complications. In some cases, experimental therapies such as stem cell transplantation or gene therapy may be used to promote tissue repair and regeneration.

... two regulators of complement. The membrane attack complex is initiated when the complement protein C5 convertase cleaves C5 ... All three pathways of the complement system (classical, lectin and alternative pathways) initiate the formation of MAC. Another ... Terminal complement pathway deficiency Paroxysmal nocturnal haemoglobinuria Perforin Pore-forming toxin Xie CB, Jane-Wit D, ... ISBN 978-0-323-54943-1. Media related to Complement membrane attack complex at Wikimedia Commons Complement+Membrane+Attack+ ...
... a stable compound which can bind an additional C3b to form alternative pathway C5-convertase. The C5-convertase of the ... The alternative pathway is one of three complement pathways that opsonize and kill pathogens. The pathway is triggered when the ... This complex is also known as a fluid-phase C3-convertase. This convertase, the alternative pathway C3-convertase, although ... After the creation of C5 convertase (either as (C3b)2BbP or C4b2a3b from the classical pathway), the complement system follows ...
The term C3 convertase may refer to: C3-convertase, an enzyme Alternative-complement-pathway C3/C5 convertase, an enzyme This ...
... or the alternative pathway (C3bBbC3b) of complement system. Two fluid phase C5 convertases have been described: the classical ... The target of C5 convertase is complement protein C5. C5 is a two-chain (α, β) plasma glycoprotein (Mr = 196,000). C5 and C3 ... The complement component C5 can be also activated by fluid phase C5 convertase. C5 is activated by CVFBb in the presence of ... "Alternative pathway of complement: Recruitment of precursor properdin by the labile C3/C5 convertase and the potentiation of ...
C3b binds to the C3 convertase (C4b2b), to form C5 convertase (C4b2b3b). C5 convertase then cleaves C5 into C5a and C5b. Like ... Alternative complement pathway - another complement system pathway Lectin pathway - another complement system pathway Noris, ... Activation of the complement pathway through the classical, lectin or alternative complement pathway is followed by a cascade ... The classical complement pathway is one of three pathways which activate the complement system, which is part of the immune ...
... complement factor I EC 3.4.21.46: complement factor D EC 3.4.21.47: alternative-complement-pathway C3/C5 convertase EC 3.4. ... classical-complement-pathway C3/C5 convertase EC 3.4.21.44: Now EC 3.4.21.43, classical-complement-pathway C3/C5 convertase EC ... classical-complement-pathway C3/C5 convertase EC 3.4.21.44: Now EC 3.4.21.43, classical-complement-pathway C3/C5 convertase EC ... 3.4.21.45: complement factor I EC 3.4.21.46: complement factor D EC 3.4.21.47: alternative-complement-pathway C3/C5 convertase ...
C5 convertase formation and cell lysis. C3 convertase can be used to refer to the form produced in the alternative pathway ( ... Hourcade D (2006). "The Role of Properdin in the Assembly of the Alternative Pathway C3 Convertases of Complement". J Biol Chem ... It is a membrane protein and regulates also C5 convertase of the classical and alternative pathway. DAF protects host cells ... Since C3 convertases cleave C3 to produce C3b which can then form an additional C3 convertase through the alternative pathway, ...
C3 nephritic factor is an autoantibody to the complement C3bBb convertase that activates the alternative complement pathway, a ... finding that suggested the potential of B cell or complement C5 depletion as adjunct therapies in certain forms of kidney ...
... components of the alternative-pathway C3 convertase of complement". The Biochemical Journal. 253 (3): 667-75. doi:10.1042/ ... Rawal N, Pangburn MK (March 2001). "Structure/function of C5 convertases of complement". International Immunopharmacology. 1 (3 ... This gene encodes complement factor B, a component of the alternative pathway of complement activation. Factor B circulates in ... The active subunit Bb is a serine protease that associates with C3b to form the alternative pathway C3 convertase. Bb is ...
... iC3b C5 - C5a C3-convertase C5-convertase Late stage Membrane attack complex (MAC) C6 C7 C8 C9 Complement pathway inhibitors C1 ... C4a C2 Mannan-binding lectin pathway MASP1 / MASP2 Mannan-binding lectin Alternative complement pathway Factor B Factor D ... system Complement system Classical complement pathway Mannan-binding lectin pathway Alternate complement pathway Complement ... divided by pathway) Classical complement pathway C1Q complex - C1R / C1S C4 - ...
Hourcade D (2006). "The Role of Properdin in the Assembly of the Alternative Pathway C3 Convertases of Complement". J Biol Chem ... This protein binds to bacterial cell walls and dying human cells to stabilize the C3 and C5-convertase enzyme complexes to form ... It binds to preformed alternative pathway C3-convertases. Properdin also inhibits the Factor H - mediated cleavage of C3b by ... The alternative pathway is not dependent on antibodies. This branch of the complement system is activated by IgA immune ...
C3b later joins with C4b2b to make C5 convertase (C4b2b3b complex). The alternative pathway is continuously activated at a low ... the classical complement pathway, the alternative complement pathway, and the lectin pathway. The alternative pathway accounts ... the alternative complement pathway is one element of innate immunity.[citation needed] Once the alternative C3 convertase ... The complex of C3b(2)Bb is a protease which cleaves C5 into C5b and C5a. C5 convertase is also formed by the classical pathway ...
... alternative pathway and lectin pathway) that ultimately lead to the formation of a C3 convertase. Formation of a C3 convertase ... In such cases treatment with the complement-inhibitory anti-C5 monoclonal antibody, eculizumab, is found to be highly effective ... Additionally, C3b plays a role in forming a C3 convertase when bound to Factor B (C3bBb complex), or a C5 convertase when bound ... Binding of a C3b molecule to the C4bC2b complex (C4b2b3b) results in the formation of a C5 convertase, which cleaves C5 into ...
... participates in all three of the complement pathways (classical, alternative, and lectin); the alternative pathway is " ... C5 binding sites, 4) private allelic residues. Additionally, the same study identified the expression of human complement C4 ... the C4b-C2a complex with protease activity has been termed the C3 convertase. Protein 4b can be further cleaved into 4c and 4d ... Complement component 4A Complement component 4B HLA A1-B8-DR3-DQ2 haplotype Complement system Complement deficiency Sekar A, ...
... complement c3-c5 convertases MeSH D12.776.124.486.274.860.387.500 - complement c3-c5 convertases, alternative pathway MeSH ... complement c5 convertase, alternative pathway MeSH D12.776.124.486.274.860.387.750 - complement c3-c5 convertases, classical ... complement c3 convertase, classical pathway MeSH D12.776.124.486.274.860.387.750.750 - complement c5 convertase, classical ... complement c3 convertase, alternative pathway MeSH D12.776.124.486.274.860.387.500.750 - ...
... amongst other complement proteins and factors, leading to regulation of the alternative pathway of complement in particular. ... and decay accelerating activity against the alternative pathway C3-convertase, C3bBb. Factor H exerts its protective action on ... January 2011). "The development of atypical hemolytic uremic syndrome depends on complement C5". Journal of the American ... Its principal function is to regulate the alternative pathway of the complement system, ensuring that the complement system is ...
The convertases of the alternative pathway of the complement system play a crucial role in complement activat … ... The complement system is a key part of innate immunity. However, if the system becomes dysregulated, damage to healthy host ... Complement C3-C5 Convertases / analysis Actions. * Search in PubMed * Search in MeSH ... The convertases of the alternative pathway of the complement system play a crucial role in complement activation. In healthy ...
i,Toxoplasma gondii,/i, actively resists complement-mediated killing in non-immune human serum (NHS) by inactivating C3b, ... Regulating complement is an important step in the establishment of infection by microbial pathogens. , ... Complement C3-C5 Convertases, Alternative Pathway Actions. * Search in PubMed * Search in MeSH ... Mechanism of complement-dependent haemolysis via the lectin pathway: role of the complement regulatory proteins. Suankratay C, ...
1. The conversion of human complement component C5 into fragment C5b by the alternative-pathway C5 convertase.. DiScipio RG. ... Surface-dependent modulation by H of C5 cleavage by the cell-bound alternative pathway C5 convertase of human complement. ... C5 convertase of the alternative pathway of complement. Kinetic analysis of the free and surface-bound forms of the enzyme. ... 9. The C3/C5 convertase of the alternative pathway of complement: stabilization and restriction of control by lanthanide ions. ...
Complement C3-C5 Convertases [D12.776.124.486.274.045.387] * Complement C3-C5 Convertases, Alternative Pathway [D12.776.124.486 ... Alternative Pathway C5 Convertase C5 Convertase (C3bBb3b) C5 Convertase, Alternative Pathway Pharm Action. Immunologic Factors ... Complement C3 Convertase, Alternative Pathway [D12.776.124.486.274.045.387.500.374] * Complement C5 Convertase, Alternative ... and COMPLEMENT C5B in the ALTERNATIVE COMPLEMENT ACTIVATION PATHWAY. It is the complex of ALTERNATIVE PATHWAY C3 CONVERTASE ( ...
Alternative Complement Pathway C3 C5 Convertase 100% * B-Cell Activating Factor 100% ...
Complement C5 Convertase, Alternative Pathway Entry term(s). Alternative Pathway C5 Convertase C5 Convertase (C3bBb3b) C5 ... Alternative pathway C5 convertase Entry term(s):. Alternative Pathway C5 Convertase. C5 Convertase (C3bBb3b). C5 Convertase, ... Complement C3-C5 Convertases, Alternative Pathway [D12.776.124.486.274.045.387.500] Complement C3-C5 Convertases, Alternative ... Complement C5 Convertase, Alternative Pathway [D12.776.124.486.274.045.387.500.750] Complement C5 Convertase, Alternative ...
Complement C3-C5 Convertases [D12.776.124.486.274.045.387] * Complement C3-C5 Convertases, Alternative Pathway [D12.776.124.486 ... Alternative Pathway C5 Convertase C5 Convertase (C3bBb3b) C5 Convertase, Alternative Pathway Pharm Action. Immunologic Factors ... Complement C3 Convertase, Alternative Pathway [D12.776.124.486.274.045.387.500.374] * Complement C5 Convertase, Alternative ... and COMPLEMENT C5B in the ALTERNATIVE COMPLEMENT ACTIVATION PATHWAY. It is the complex of ALTERNATIVE PATHWAY C3 CONVERTASE ( ...
Alternative Complement Pathway C3 C5 Convertase Medicine and Dentistry 100% * Nuclear Factor Medicine and Dentistry 100% ...
NFt stabilizes the alternative pathway properdin-dependent C3/C5 convertase (C3Bb2,Bb,P) and leads to C3 activation and ... NFa stabilizes the alternative pathway convertase and results in complement activation and chronic C3 consumption. Deficiency ... The alternative pathway utilizes C3 and factors B and D to form the alternative pathway convertase C3b,Bb. ... NFt stabilizes the alternative pathway properdin-dependent C3/C5 convertase (C3Bb2,Bb,P) and also activates the terminal ...
Alternative Complement Pathway C3 C5 Convertase 100% * Transcription Factor RUNX2 100% * Aorta 74% ... Deletion of SOCS2 Reduces Post-Colitis Fibrosis via Alteration of the TGF$ Pathway. Al-Araimi, A., Al Kharusi, A., Bani Oraba, ...
Alternative Complement Pathway C3 C5 Convertase 33% * Hydroxyl Radical 33% * Hydroxylation 33% ...
... is a positive regulatory protein that stabilizes the C3 convertase and C5 convertase of the complement alternative pathway (AP ... Complement factor H (CFH) is the major inhibitor of the alternative pathway of the complement system and is structurally ... Complement activation likely via an alternative pathway (increased C3b, sC5b-9, and CH50) may play a role in the pathogenesis ... The alternative complement pathway activation product Ba as a marker for transplant-associated thrombotic microangiopathy. ...
This gene encodes complement factor B, a component of the alternative pathway of complement activation. Factor B circulates in ... Bb, a serine protease, then combines with complement factor 3b to generate the C3 or C5 convertase. It has also been implicated ... The active subunit Bb is a serine protease which associates with C3b to form the alternative pathway C3 convertase. Bb is ... Upon activation of the alternative pathway, it is cleaved by complement factor D yielding the noncatalytic chain Ba and the ...
The complement system is an evolutionarily ancient key component of innate immunity required for the detection and removal of ... Upon subsequent generation of C5 convertase (C4bC2aC3b for the classical and lectin pathways and C3bBbC3b for the alternative ... and the alternative pathway. Through the formation of classical (C4b2b) and alternative (C3bBb) C3 convertases, these pathways ... The asterisk denotes that C3 and C5 convertases or C3 and/or C5-activating proteases operate in parallel with intracellularly ...
All three pathways of the complement system (classical, lectin and alternative pathways) initiate the formation of MAC. Another ... The membrane attack complex is initiated when the complement protein C5 convertase cleaves C5 into C5a and C5b. ... is generated on activation of complement and contains the complement proteins C5b, C6, C7, C8, C9 together with the regulatory ... C3b is the larger of two elements formed by the cleavage of complement component 3, and is considered an important part of the ...
Alternative PathwayComplement C1 Inhibitor ProteinImmunoglobulin GComplement C3 Convertase, Alternative PathwayComplement C5 ... Complement C3Complement C4Complement C4aComplement C3aComplement C1qComplement C5aComplement C4bComplement C5Complement C3b ... Complement C3Complement C4Complement C4aComplement C3aComplement C1qComplement C5aComplement ActivationComplement C4bComplement ... Complement C5 Convertase, Alternative Pathway. A serine protease that cleaves multiple COMPLEMENT C5 into COMPLEMENT C5A ( ...
Anti-Human Complement factor B/Ba Monoclonal Antibody (clone M20/6) -0.5 mg is available from creative biolabs. ... Factor B provides the catalytic subunit of the C3/C5 convertase that replaces the complement pathway. The assembly of C3 ... This provides a positive amplification loop for the classical and alternative complement pathways. Bb (MW 60 kD) is the serine ... C5 convertase ((C3b)2Bb) is formed. The Bb fragment may be regarded as a better indicator of the complement activation pathway ...
The alternative pathway of complement represents an important humoral component of natural defense against microbial attack. ... and C5-convertases, i.e. C3bBb and C3bBbC3b(n). These multicomponent enzymes assemble on the surface of alternative pathway of ... The alternative pathway of complement represents an important humoral component of natural defense against microbial attack. ... Factor D is the rate-linking C3 convertase enzyme of the alternative pathway. Furthermore, factor D plays a role in fatty ...
... of the FHRs with pentraxins resulted in enhanced activation of both the classical and the alternative complement pathways on ... of the FHRs with pentraxins resulted in enhanced activation of both the classical and the alternative complement pathways on ... Factor H (FH), a major soluble complement inhibitor, binds to dead cells and inhibits excessive complement activation on their ... Factor H (FH), a major soluble complement inhibitor, binds to dead cells and inhibits excessive complement activation on their ...
This complex is a C3/C5 convertase that cleaves both complement components C3 and C5. Unlike endogenous C3b/Bb, CVF/Bb is a ... and alternative pathways), and its various activation products are crucial for mediating, directly or indirectly, virtually all ... complement component C3 is the most important protein of the complement system as it is activated by all three pathways ( ... In venom, complement C3 homolog is a structural and functional analog of complement component C3b, the activated form of C3. ...
HN - 2006 (1978) BX - C3 Convertase MH - Complement C3-C5 Convertases, Alternative Pathway UI - D050578 MN - D12.776.124.486. ... They cleave COMPLEMENT C3 and COMPLEMENT C5. HN - 2006 MH - Complement C3-C5 Convertases, Classical Pathway UI - D050579 MN - ... and COMPLEMENT C5B in the ALTERNATIVE COMPLEMENT ACTIVATION PATHWAY. It is the complex of ALTERNATIVE PATHWAY C3 CONVERTASE ( ... PATHWAY. It is a complex of COMPLEMENT 4B and COMPLEMENT 2A (C4b2a). HN - 2006 MH - Complement C3-C5 Convertases UI - D050577 ...
Site 1 (CCPs 1-3) alone mediated the decay acceleration of the classical and alternative pathway C3 convertases. Site 2 (CCPs 8 ... Site 1 (CCPs 1-3) alone mediated the decay acceleration of the classical and alternative pathway C3 convertases. Site 2 (CCPs 8 ... Site 1 (CCPs 1-3) alone mediated the decay acceleration of the classical and alternative pathway C3 convertases. Site 2 (CCPs 8 ... Site 1 (CCPs 1-3) alone mediated the decay acceleration of the classical and alternative pathway C3 convertases. Site 2 (CCPs 8 ...
The purified refolded recombinant protein was active against both classical and alternative pathway assays of complement ... In addition to understanding the mechanism of complement inhibition by DAF through structural studies, there is also an ... thus permitting the first detailed X-ray crystallography studies on a functionally active human complement regulator protein ... is a glycophosphatidyl inositol-anchored glycoprotein that regulates the activity of C3 and C5 convertases. ...
The database captures an improved coverage of the innate immunity interactome by integrating known interactions and pathways ... experimentally-verified interactions and signaling pathways involved in the innate immune response of humans, mice and bovines ... a major oral and systemic pathogen with complement C5 convertase-like activity, synergizes with C5a (fragment of complement ... a chief component of complement activation produced via all three complement pathways (i.e., lectin, classical, and alternative ...
... the alternative complement pathway by blocking formation and accelerating the decay of alternative pathway C3 convertases; it ... 30] such as C3 inhibitor intravitreal compstatin/POT-4, anti-C5 antibody, C5 inhibitor ARC1905, antibody against complement ... 21] Such rare variants have been described in the complement factor H (CFH), complement factor I (CFI), complement factor 9 (C9 ... 11] as well as other genes: factor B (BF)/complement component 2 (C2), [11, 12] complement component 3 (C3), [13, 14] and ...
The C3 and C5 convertases are enzymatic complexes that initiate and amplify the activity of the complement pathways and ... Alternative Names: C1-INH, C1 esterase inhibitor. Assay Background. The complement system plays important roles in both innate ... There are three pathways of complement activation. The classical pathway (CP) is initiated by Immune complexes; the lectin ... Each generates a C3 convertase, a serine protease that cleaves the central complement protein C3, and generates the major ...
Alternative Pathway N0000169299 Complement C5 Convertase, Classical Pathway N0000169288 Complement C5a N0000169289 Complement ... Alternative Pathway N0000169298 Complement C3-C5 Convertases, Classical Pathway N0000169287 Complement C3a N0000169279 ... Pathway N0000169359 Complement C3 Nephritic Factor N0000169293 Complement C3-C5 Convertases N0000169294 Complement C3-C5 ... Complement C4b N0000169308 Complement C4b-Binding Protein N0000169274 Complement C5 N0000169296 Complement C5 Convertase, ...
Lucio Luzzatto on Complement in PNH and other hemolytic anaemias 1, part of a collection of multimedia lectures. ... that is hydrolyzed by what is called the C5 convertase, of which there are two types, one produced by the alternative pathways ... The evolution of complement and the alternative pathway The evolution of complement and the alternative pathway ... complement can be activated through different mechanisms which are referred to as the classic pathway, the alternative pathway ...
C5 Convertase, Alternative Pathway use Complement C5 Convertase, Alternative Pathway C5 Convertase, Classical use Complement C5 ... C5 Convertase (C3bBb3b) use Complement C5 Convertase, Alternative Pathway C5 Convertase (C4b2a3b) use Complement C5 Convertase ... C3 Convertase, Alternative Pathway use Complement C3 Convertase, Alternative Pathway C3 Convertase, Classical use Complement C3 ... C3 Convertase (C3bBb) use Complement C3 Convertase, Alternative Pathway C3 Convertase (C4b2a) use Complement C3 Convertase, ...
From NCBI Gene: This gene encodes complement factor B, a component of the alternative pathway of complement activation. Factor ... The active subunit Bb is a serine protease which associates with C3b to form the alternative pathway C3 convertase. Bb is ... Upon activation of the alternative pathway, it is cleaved by complement factor D yielding the noncatalytic chain Ba and the ... The polyadenylation site of this gene is 421 bp from the 5 end of the gene for complement component 2. [provided by RefSeq, ...
  • A serine protease that cleaves multiple COMPLEMENT C5 into COMPLEMENT C5A (anaphylatoxin) and COMPLEMENT C5B in the ALTERNATIVE COMPLEMENT ACTIVATION PATHWAY . (nih.gov)
  • The membrane attack complex is initiated when the complement protein C5 convertase cleaves C5 into C5a and C5b. (promisekit.org)
  • The minor fragment formed when C5 convertase cleaves C5 into C5a and COMPLEMENT C5B. (lookformedical.com)
  • This complex is a C3/C5 convertase that cleaves both complement components C3 and C5. (expasy.org)
  • Each generates a C3 convertase, a serine protease that cleaves the central complement protein C3, and generates the major cleavage fragment C3b. (eaglebio.com)
  • 37. Interaction of C3b(2)--IgG complexes with complement proteins properdin, factor B and factor H: implications for amplification. (nih.gov)
  • The soluble membrane attack complex (sMAC, a.k.a., sC5b-9 or TCC) is generated on activation of complement and contains the complement proteins C5b, C6, C7, C8, C9 together with the regulatory proteins clusterin and/or vitronectin. (promisekit.org)
  • The interaction of the proteins C3, factor B, and factor D results in the formation of the alternative C3- and C5-convertases, i.e. (hycultbiotech.com)
  • The FH-related (FHR) proteins share common ligands with FH, due to their homology with this complement regulator, but they lack the domains that mediate the complement inhibitory activity of FH. (frontiersin.org)
  • Based on these results, we generated proteins one-fourth the size of CR1 but with enhanced decay accelerating activity for the C3 convertases. (wustl.edu)
  • Factor H and other complement proteins regulate the amplification of C3 activation [ 8 ]. (chikd.org)
  • It is the complex of ALTERNATIVE PATHWAY C3 CONVERTASE (C3bBb) with an additional COMPLEMENT C3B , or C3bBb3b. (nih.gov)
  • 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. (lookformedical.com)
  • The assembly of C3 convertase (C3bBb) requires the combination of factor B and C3b (C3.H2O), and factor D-mediated cleavage of the binding factor B leads to the release of Ba (MW 33 kD). (creative-biolabs.com)
  • Properdin can bind C3b and activate the alternative complement pathway and also stabilizes the C3bBb alternative pathway C3 convertase enzyme, thereby directing the deposition of C3 fragments to the cell surface and driving the amplification loop ( 17 - 19 ). (frontiersin.org)
  • Bb, a serine protease, then combines with complement factor 3b to generate the C3 or C5 convertase. (nih.gov)
  • The active subunit Bb is a serine protease which associates with C3b to form the alternative pathway C3 convertase. (nih.gov)
  • Factor D, a 24 kD serine protease of the alternative complement pathway, is synthesized as a precursor single-chain molecule. (hycultbiotech.com)
  • C3b is an opsonin itself, and C3 convertase facilitates the activation of the terminal pathway and the formation of the membrane attack complex C5b-9. (medscape.com)
  • The major fragment C5b binds to the membrane initiating the spontaneous assembly of the late complement components, C5-C9, into the MEMBRANE ATTACK COMPLEX. (lookformedical.com)
  • Serum glycoproteins participating in the host defense mechanism of COMPLEMENT ACTIVATION that creates the COMPLEMENT MEMBRANE ATTACK COMPLEX. (lookformedical.com)
  • C6 is the next complement component to bind to the membrane-bound COMPLEMENT C5B in the assembly of MEMBRANE ATTACK COMPLEX. (lookformedical.com)
  • 26. Regulation of the amplification C3 convertase of human complement by an inhibitory protein isolated from human erythrocyte membrane. (nih.gov)
  • Unlike endogenous C3b/Bb, CVF/Bb is a stable complex which is completely resistant to the actions of complement inhibitory factors H (CFH) and I (CFI) . (expasy.org)
  • Also, please note that, what is in black are the activation pathways, what is in red are the inhibitory elements in the complexity of the system. (hstalks.com)
  • We observed reduced complement activation when FXI activation was inhibited in a baboon model of lethal systemic inflammation, suggesting cross-talk between FXI and the complement cascade. (bvsalud.org)
  • 23. Analysis of the interaction between properdin and factor B, components of the alternative-pathway C3 convertase of complement. (nih.gov)
  • 30. C3 and C5-cleaving properdin enzymes formed on zymosan incubated with human serum: the decay and the regeneration of the enzymes. (nih.gov)
  • 31. The Role of Properdin in C5 Convertase Activity and C5b-9 Formation in the Complement Alternative Pathway. (nih.gov)
  • 39. The role of properdin in the assembly of the alternative pathway C3 convertases of complement. (nih.gov)
  • C3 convertase is stabilized by the binding of properdin. (creative-biolabs.com)
  • These multicomponent enzymes assemble on the surface of alternative pathway of complement activators and are stabilized by properdin (P). The participation of the alternative pathway of complement has been implicated in the pathogenesis of a wide variety of human diseases. (hycultbiotech.com)
  • HG-4, a monoclonal antibody that targets MASP-2, a key enzyme in the lectin pathway, inhibited lectin pathway functional activity in vitro, with an IC50 of circa 10nM. (bvsalud.org)
  • The monoclonal antibody M20/6 recognizes human complement factor B/Ba. (creative-biolabs.com)
  • C3G complement blockade with eculizumab, a monoclonal antibody targeted against complement C5, inhibits activation of the alternative complement pathway. (chikd.org)
  • Recently, plasma exchange/plasma infusion and provision of eculizumab, a monoclonal antibody against C5, can be used in cases of nephritic syndrome and/or decreased renal function in patients with C3GN. (chikd.org)
  • Complement factor H (CFH) is the major inhibitor of the alternative pathway of the complement system and is structurally related to beta2-glycoprotein I, which itself is known to bind to ligands, including coagulation factor XI (FXI). (bvsalud.org)
  • Our study provides, to our knowledge, a novel molecular link between the contact pathway of coagulation and the complement system. (bvsalud.org)
  • 27. C5 convertase of the alternative complement pathway: covalent linkage between two C3b molecules within the trimolecular complex enzyme. (nih.gov)
  • Factor D is the rate-linking C3 convertase enzyme of the alternative pathway. (hycultbiotech.com)
  • The human complement factor D ELISA is a ready-to-use solid-phase enzyme-linked immunosorbent assay based on the sandwich principle with a working time of 3½ hours. (hycultbiotech.com)
  • use DICARBOXYLIC ACIDS 1970-1979 MH - 3-Phosphoshikimate 1-Carboxyvinyltransferase UI - D051229 MN - D8.811.913.225.735 MS - An enzyme of the shikimate pathway of AROMATIC AMINO ACID biosynthesis, it generates 5-enolpyruvylshikimate 3-phosphate and ORTHOPHOSPHATE from PHOSPHOENOLPYRUVATE and SHIKIMATE-3-PHOSPHATE. (nih.gov)
  • 21. C3 nephritic factor (C3NeF): stabilization of fluid phase and cell-bound alternative pathway convertase. (nih.gov)
  • Small amounts of C3b are constantly being formed in the circulation, which are inactivated by factors H and I. The binding of C3b to a foreign antigen decreases its affinity for factor H and allows for the formation of increasing amounts of the alternate pathway convertase. (medscape.com)
  • Impairment of the complement regulatory protein Factor H (FH) is implicated in the physiopathological mechanisms of different diseases like atypical hemolytic and uremic syndrome and C3 glomerulopathies. (bvsalud.org)
  • Factor B which is part of the alternate pathway of the complement system is cleaved by factor D into 2 fragments: Ba and Bb. (nih.gov)
  • This gene encodes complement factor B, a component of the alternative pathway of complement activation. (nih.gov)
  • Upon activation of the alternative pathway, it is cleaved by complement factor D yielding the noncatalytic chain Ba and the catalytic subunit Bb. (nih.gov)
  • 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. (lookformedical.com)
  • 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). (lookformedical.com)
  • Complement factor B is a single-chain molecule of 764 amino acids (with a molecular weight of 90 kD), including a leader peptide of 25 amino acids. (creative-biolabs.com)
  • Factor B provides the catalytic subunit of the C3/C5 convertase that replaces the complement pathway. (creative-biolabs.com)
  • In addition to complement activation, factor B fragments also participate in other immune functions. (creative-biolabs.com)
  • Furthermore, factor D plays a role in fatty tissue distinct from its role as a complement protein. (hycultbiotech.com)
  • The human complement factor D ELISA kit is to be used for the in vitro quantitative determination of human complement factor D in serum, plasma and urine samples. (hycultbiotech.com)
  • Samples and standards are incubated in microtiter wells coated with antibodies recognizing human complement factor D. Biotinylated tracer antibody will bind to the captured human complement factor D. Streptavidin-peroxidase conjugate will bind to the biotinylated tracer antibody. (hycultbiotech.com)
  • A standard curve is obtained by plotting the absorbance (linear) versus the corresponding concentrations of the human complement factor D standards (log). (hycultbiotech.com)
  • The human complement factor D concentration of samples, which are run concurrently with the standards, can be determined from the standard curve. (hycultbiotech.com)
  • Factor H (FH), a major soluble complement inhibitor, binds to dead cells and inhibits excessive complement activation on their surface, preventing lysis, and the release of intracellular material, including DNA. (frontiersin.org)
  • Notably, these pentraxins may also recruit soluble complement regulators, such as factor H (FH) and C4b-binding protein (C4BP), which in turn limit excessive complement activation on the surface ( 11 - 14 ). (frontiersin.org)
  • Decay-accelerating factor (DAF, CD55) is a glycophosphatidyl inositol-anchored glycoprotein that regulates the activity of C3 and C5 convertases. (ox.ac.uk)
  • The common coding variant Y402H in the complement factor H ( CFH ) gene was the first identified. (medscape.com)
  • [ 21 ] Such rare variants have been described in the complement factor H ( CFH ), complement factor I ( CFI ), complement factor 9 ( C9 ), and complement factor 3 ( C3) genes. (medscape.com)
  • 29. Role of the C3b-binding site on C4b-binding protein in regulating classical pathway C5 convertase. (nih.gov)
  • Another complement protein, C6, binds to C5b. (promisekit.org)
  • In mammals , complement component C3 is the most important protein of the complement system as it is activated by all three pathways (classical, lectin, and alternative pathways), and its various activation products are crucial for mediating, directly or indirectly, virtually all biological functions of complement. (expasy.org)
  • The purified refolded recombinant protein was active against both classical and alternative pathway assays of complement activation and had similar biological activity to soluble human DAF expressed in Pichia pastoris. (ox.ac.uk)
  • Crystals of the E. coli-derived protein were obtained and diffracted to 2.2 Å, thus permitting the first detailed X-ray crystallography studies on a functionally active human complement regulator protein with direct therapeutic potential. (ox.ac.uk)
  • To that end, truncated derivatives of CR1 whose extracellular part is composed of 30 tandem repeating modules, termed complement control protein repeats (CCPs), were generated. (wustl.edu)
  • Homo sapiens] C5AR1 engage in crosstalk with TLR2 and Porphyromonas gingivalis, a major oral and systemic pathogen with complement C5 convertase-like activity, synergizes with C5a (fragment of complement protein C5) to increase cyclic adenosine monophosphate (cAMP) concentrations, resulting in suppression of macrophage immune function and enhanced pathogen survival. (innatedb.com)
  • multiple cross-links are organic in often all normal surfaces where they suffer acylated first pathways been on their G-protein download data mining and predictive analysis intelligence gathering and. (evakoch.com)
  • The classic and alternate pathway convertases cause C3 activation, forming C3a and C3b. (medscape.com)
  • C3b is the larger of two elements formed by the cleavage of complement component 3, and is considered an important part of the innate immune system. (promisekit.org)
  • The smaller fragment generated from the cleavage of complement C3 by C3 CONVERTASE. (lookformedical.com)
  • Here, we tested whether inhibition of the lectin pathway of complement could reduce the pathology and improve the outcomes in a murine model of LPS-induced lung injury that closely mimics ARDS in human. (bvsalud.org)
  • This binding initiates deposition of the complement activation products C3b, C4b and C5b-9 on LPS via the lectin pathway. (bvsalud.org)
  • Administration of HG4 (5mg/kg) in mice led to almost complete inhibition of the lectin pathway activation for 48hrs, and 50% inhibition at 60hrs post administration. (bvsalud.org)
  • Inhibition of the lectin pathway in mice prior to LPS-induced lung injury improved all pathological markers tested. (bvsalud.org)
  • Toxoplasma activated both the lectin (LP) and alternative (AP) pathways, and the deposition of C3b was both strain and lectin-dependent. (nih.gov)
  • Dying cells also expose ligands that bind initiator molecules of the various complement pathways, so that complement activation and opsonin deposition on the dead cell surface may enhance phagocytotic clearance ( 1 , 8 ). (frontiersin.org)
  • Factors initiating complement activation include ANTIGEN-ANTIBODY COMPLEXES, microbial ANTIGENS, or cell surface POLYSACCHARIDES. (lookformedical.com)
  • The complement system is a key humoral component of innate immunity, and in addition to its many other functions, it is involved in the clearance of waste material, such as immune complexes and apoptotic and necrotic cells ( 1 , 2 ). (frontiersin.org)
  • The C3 and C5 convertases are enzymatic complexes that initiate and amplify the activity of the complement pathways and ultimately generate the cytolytic MAC (C5b-9). (eaglebio.com)
  • 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. (lookformedical.com)
  • Site 1 (CCPs 1-3) alone mediated the decay acceleration of the classical and alternative pathway C3 convertases. (wustl.edu)
  • 40. Inhibition of human complement by a C3-binding peptide isolated from a phage-displayed random peptide library. (nih.gov)
  • In addition to understanding the mechanism of complement inhibition by DAF through structural studies, there is also an interest in the possible therapeutic potential of the molecule. (ox.ac.uk)
  • The classic pathway is activated by the interaction of C1 with an antigen-antibody complex. (medscape.com)
  • This interaction results in the formation of C4b2a, which is the classic pathway C3b convertase. (medscape.com)
  • First of all, complement can be activated through different mechanisms which are referred to as the classic pathway, the alternative pathway based on bacterial life of polysaccharide, and the alternative pathway based on spontaneous hydrolysis of C3. (hstalks.com)
  • So, these three pathways, one, two and three, they all converge on one component called C5, that is hydrolyzed by what is called the C5 convertase, of which there are two types, one produced by the alternative pathways and the other produced by the classic pathway. (hstalks.com)
  • But when an antigen-antibody reaction takes place here then C1q is recruited, the classic pathway starts. (hstalks.com)
  • This provides a positive amplification loop for the classical and alternative complement pathways. (creative-biolabs.com)
  • 22. Covalent association of C3b with C4b within C5 convertase of the classical complement pathway. (nih.gov)
  • In vitro, LPS binds to murine and human collectin 11, human MBL and murine MBL-A, but not to C1q, the recognition subcomponent of the classical pathway. (bvsalud.org)
  • All three pathways of the complement system (classical, lectin and alternative pathways) initiate the formation of MAC. (promisekit.org)
  • A glycoprotein that is central in both the classical and the alternative pathway of COMPLEMENT ACTIVATION. (lookformedical.com)
  • 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. (lookformedical.com)
  • Interactions of the FHRs with pentraxins resulted in enhanced activation of both the classical and the alternative complement pathways on dead cells when exposed to human serum. (frontiersin.org)
  • The initiator molecules of the classical (C1q) and lectin pathways (e.g. (frontiersin.org)
  • Clinical presentations are similar for the three types of MPGN, but they manifest somewhat different mechanisms of complement activation and predisposition to recur in kidney transplants. (medscape.com)
  • Complement activation in ARDS initiates a robust inflammatory reaction that can cause progressive endothelial injury in the lung. (bvsalud.org)
  • The Bb fragment may be regarded as a better indicator of the complement activation pathway than Ba, because impaired renal filtration does directly affect Ba levels. (creative-biolabs.com)
  • Because their roles in complement regulation is controversial and incompletely understood, we studied the interaction of FHR-1 and FHR-5 with DNA and dead cells and investigated whether they influence the regulatory role of FH and the complement activation on DNA and dead cells. (frontiersin.org)
  • Both FHRs caused increased complement activation on DNA. (frontiersin.org)
  • [ 3 ] The existence of multiple, complement-related AMD risk alleles has lent further support to this theory and has shed light on the role of uncontrolled alternative complement pathway activation in this disease. (medscape.com)
  • There are three pathways of complement activation. (eaglebio.com)
  • As a result the activation of the complement system is blocked. (eaglebio.com)
  • And this can work at about thousand times faster than the spontaneous complement activation. (hstalks.com)
  • But the spontaneous complement activation means that all the time, the complement must be regulated in order, as I said before, to avoid mischief. (hstalks.com)
  • In affected patients, the alternative pathway produces C3 convertase, which amplifies C3 activation, resulting in the creation of C3b particles, and finally, the formation of C5 convertase to assemble MAC C5b-9. (chikd.org)
  • The larger fragment C3b binds with C3 convertase to form C5 convertase. (lookformedical.com)
  • The alternative pathway of complement represents an important humoral component of natural defense against microbial attack. (hycultbiotech.com)
  • Toxoplasma gondii actively resists complement-mediated killing in non-immune human serum (NHS) by inactivating C3b, however the precise molecular basis is unknown. (nih.gov)
  • A 105-kDa serum glycoprotein with significant homology to the other late complement components, C7-C9. (lookformedical.com)
  • The complement system is an evolutionarily ancient key component of innate immunity required for the detection and removal of invading pathogens. (nih.gov)
  • The complement system plays important roles in both innate and adaptive immune response and can produce an inflammatory and protective reaction to challenges from pathogens before an adaptive response can occur. (eaglebio.com)
  • The leukocyte-specific complement receptor 3 (CR3, αMß2, CD11b/CD18) and complement receptor 4 (CR4, αXß2, CD11c/CD18) belong to the family of ß2-integrins. (bvsalud.org)
  • Decay accelerating activity of complement receptor type 1 (CD35). (wustl.edu)
  • Dive into the research topics of 'Decay accelerating activity of complement receptor type 1 (CD35). (wustl.edu)
  • The polyadenylation site of this gene is 421 bp from the 5' end of the gene for complement component 2. (nih.gov)
  • The smaller fragment formed when complement C4 is cleaved by COMPLEMENT C1S. (lookformedical.com)
  • The biochemical basis of these, what are being called pathways but also being called cascades, is in general and that there are enzymatic reactions. (hstalks.com)
  • 34. Formation of high-affinity C5 convertases of the alternative pathway of complement. (nih.gov)
  • 33. The interaction of glycoprotein C of herpes simplex virus types 1 and 2 with the alternative complement pathway. (nih.gov)
  • 36. The low C5 convertase activity of the C4A6 allotype of human complement component C4. (nih.gov)
  • These results suggest that FXIa generation enhances the activity of the complement system and thus may potentiate the immune response. (bvsalud.org)
  • Therefore, CVF continuously activates complement, resulting in the depletion of complement activity. (expasy.org)
  • In contrast, for the C5 convertase, site 1 had only 0.5% of the decay accelerating activity, while site 2 had no detectable activity. (wustl.edu)
  • Efficient C5 decay accelerating activity was detected in recombinants that carried both site 1 and site 2. (wustl.edu)
  • The results indicate that, for the C5 convertases, decay accelerating activity is mediated primarily by site 1. (wustl.edu)
  • The normal complement system consists of the classic and alternative pathways. (medscape.com)
  • It is unknown whether FXI or its activated form, activated FXI (FXIa), directly interacts with the complement system. (bvsalud.org)
  • In particular, work on the impact of complement on T cell responses led to the surprising discoveries that the complement system also functions within cells and is involved in regulating basic cellular processes, predominantly those of metabolic nature. (nih.gov)
  • Rare genetic variants in the complement system have also been found to play an important role in AMD. (medscape.com)
  • I will not discuss in detail the complement system which is illustrated here in this pathway. (hstalks.com)
  • 2-5 The complement system recognizes features of microbial surfaces andmarks them for destruction by coating them with C3b. (qinqianshan.com)
  • 32. Interaction of beta1H globulin with cell-bound C3b: quantitative analysis of binding and influence of alternative pathway components on binding. (nih.gov)
  • The alternative pathway utilizes C3 and factors B and D to form the alternative pathway convertase C3b,Bb. (medscape.com)
  • Several genes not involved in the complement cascade have also been implicated. (medscape.com)
  • Regulating complement is an important step in the establishment of infection by microbial pathogens. (nih.gov)
  • Both C3GN and idiopathic MPGN are caused by alternative complement pathway activations [ 3 ]. (chikd.org)
  • Recently, new therapies have been suggested to target complement pathways, owing to an improvement in the understanding of the pathogenesis of C3G. (chikd.org)
  • The first one is dedicated to explore the FH capacity to dissociate the alternative pathway C3 convertase, whereas the second one is designed to explore the capacity of FH to bind cell surfaces and to protect them from complement attack. (bvsalud.org)
  • In venom , complement C3 homolog is a structural and functional analog of complement component C3b, the activated form of C3. (expasy.org)
  • I will start with other hemolytic anaemias and then I will continue with Paroxysmal Nocturnal Hemoglubinuria or PNH, a disease on which I've worked on for many years, and in which the role of complement is particularly prominent and also important because it has been the target of a new form of therapy. (hstalks.com)
  • C3GN also includes disease entities associated with complement mutation, which is causally associated with the underlying renal pathology, such as familial DDD with C3 mutation and familial C3GN with mutations in the CFHR genes. (chikd.org)
  • The only other point I'd like to particularly bring to your attention is this, the alternative pathway shown here called spontaneous C3 hydrolysis means that at a low rate, the complement is activated all the time. (hstalks.com)