title: Functional and antigenic properties of complement receptor type 2, CR2.
abstract: This is the first report demonstrating that C3d receptor (CR2) has functional activity in regulating complement cascade. Purified CR2 was examined for its cofactor activity in factor I-mediated cleavage of membrane-bound iC3b. CR2 plus C3b inactivator (I) released C3c from EA 125I-iC3b, and the release was inhibited when CR2 was preincubated with OKB7 monoclonal anti-CR2. Furthermore, immunoelectroblotting analysis showed crossreactivity of CR2 with 57H anti-CR1. These results indicate that CR2 has functional and antigenic similarity to CR1, thus providing a supporting evidence for placement of CR2 as a member of the recently defined gene family of C3- and C4-regulatory proteins composed of CR1, C4-binding protein, and factor H.
mesh_terms: D003101:Collodion; D003429:Cross Reactions; D004591:Electrophoresis, Polyacrylamide Gel; D000939:Epitopes; D006801:Humans; D010209:Paper; D011951:Receptors, Complement / Q000276:immunology*; D017464:Receptors, Complement 3d
chemical_list: D000939:Epitopes; D011951:Receptors, Complement; D017464:Receptors, Complement 3d; D003101:Collodion