| C1a | activated first component of complement |
|---|---|
| C1 INH | inhibitor of first component of complement |
| C2 | second cervical nerve; second cervical vertebra; second component of complement |
| C2a | activated second component of complement |
| C3 | third cervical nerve; third cervical vertebra; third component of complement |
| complement 5a | <chemical> Smaller fragment formed when c5 convertase splits c5 into c5a and c5b. C5a is a 74-amino acid peptide that includes a carboxy-terminal arginine crucial for its spasmogenic activity and a carbohydrate moiety. C5a is the most potent anaphylatoxin mediating immediate hypersensitivity. Chemical name: Complement C5a (12 Dec 1998) |
|---|---|
| complement 5a, des-arginine | Complement 5a with the carboxy-terminal arginine removed. The arginine is rapidly cleaved from the c5a fragment during complement activation by carboxypeptidase b present in normal human serum. C5a des-arg shows complete loss of spasmogenic activity though it retains some chemotactic ability. (12 Dec 1998) |
| complement 6 | The sixth component in the complement reaction sequence. It is a beta-globulin with a sedimentation coefficient of 8.7 and a molecular weight of 120,000 at 60 micrograms/ml in serum. It may exist in a complex with c5 and c7 and is activated by the binding of c5. (12 Dec 1998) |
| complement 7 | The seventh component in the complement reaction sequence. It is a beta-globulin probably in a complex with c5 and c6 and is activated by c5. The attachment of c7 renders the cell susceptible to lysis. (12 Dec 1998) |
| complement 8 | The next to the last essential component for cell lysis in the complement reaction sequence. It is a gamma-globulin with a molecular weight of 150,000 and a sedimentation coefficient of 8. It is present in trace amounts in serum and can be inhibited, like complement 1, by cation chelators. (12 Dec 1998) |
| complement 9 | The last component in the complement reaction sequence. It is an alpha-globulin present in serum as a trace, with a molecular weight of 80,000 and a sedimentation coefficient of 4.5. For cell lysis, it can be replaced by a metal chelator. (12 Dec 1998) |
| complement activating enzymes | <enzyme> Enzymes present in the complement system which activate one or more components in the system. Registry number: EC 3.- (12 Dec 1998) |
| complement activation | The sequential activation of serum components c1 through c9, initiated by an erythrocyte-antibody complex or by microbial polysaccharides and properdin, and producing an inflammatory response. (12 Dec 1998) |
| complement binding assay | A test for the detection of immune complexes. (05 Mar 2000) |
| complement chemotactic factor | The activated complex of the fifth, sixth, and seventh components of complement (C567) which induces chemotaxis in the case of polymorphonuclear leukocytes. (05 Mar 2000) |
| complement cytolysis inhibitor | <protein> Vertebrate glycoprotein of uncertain function. Secreted as a 400 amino acid peptide, then cleaved to form two 200 amino acid peptides that are linked by a disulphide bridge. Synonym: complement associated protein, complement cytolysis inhibitor, glycoprotein III. (11 Jan 1998) |
| complement factor h | <chemical> A beta-globulin that binds to complement 3b and makes ic3b (inactivated complement 3b) susceptible to cleavage by complement factor I. Complement factor h also acts as an alternative pathway complement inhibitor by interfering with the binding of properdin factor b to c3b. Chemical name: Complement factor H (12 Dec 1998) |
| complement factor I | <enzyme> Serine proteinase that acts on ic3b (inactivated complement 3b) to cleave it into c3c and c3dg with the help of a trypsin-like proteolytic enzyme. Complement factor I was formerly called kaf, c3binf, or enzyme 3b inactivator. Registry number: EC 3.4.21.45 (12 Dec 1998) |
| complement fixation | <immunology> Binding of complement as a result of its interaction with immune complexes (the classical pathway) or particular surfaces (alternative pathway). (18 Nov 1997) |
| complement-fixation reaction | <immunology> Binding of complement as a result of its interaction with immune complexes (the classical pathway) or particular surfaces (alternative pathway). (18 Nov 1997) |