Complement C4 Antibodies

Target Information

This gene encodes the acidic form of complement factor 4, part of the classical activation pathway. The protein is expressed as a single chain precursor which is proteolytically cleaved into a trimer of alpha, beta, and gamma chains prior to secretion. The trimer provides a surface for interaction between the antigen-antibody complex and other complement components. The alpha chain may be cleaved to release C4 anaphylatoxin, a mediator of local inflammation. Deficiency of this protein is associated with systemic lupus erythematosus and type I diabetes mellitus. This gene localizes to the major histocompatibility complex (MHC) class III region on chromosome 6. Varying haplotypes of this gene cluster exist, such that individuals may have 1, 2, or 3 copies of this gene.

Synonyms

acidic C4; acidic complement C4; Basic complement C4; C3 and PZP-like alpha-2-macroglobulin domain-containing protein 2; C3 and PZP-like alpha-2-macroglobulin domain-containing protein 3; C4; c4 complement; C4-1; C4a; C4a anaphylatoxin; C4A2; C4A3; C4A4; C4A6; C4AD; C4B; C4B_2; C4B1; C4B12; C4B2; C4B3; C4B5; C4b-A; C4b-B; C4BD; C4d-A; C4d-B; C4F; C4S; CH; Chido form of C4; CO4; Complement C4; Complement C4 alpha chain; Complement C4 beta chain; Complement C4 gamma chain; Complement C4-A; Complement C4-A alpha chain; Complement C4-B; Complement C4-B alpha chain; complement C4B1a; complement component 4 (within H-2S); complement component 4, gene 1; complement component 4A (Rodgers blood group); complement component 4B (Chido blood group); complement component 4B (Childo blood group); CPAMD2; CPAMD3; DADB-112B14.11; DAMC-258G8.6; FLJ60561; MGC164979; MHC class III region complement; RG; Rodgers form of C4; sex-limited protein; Slp; Ss