title: Rodgers (Rg) and Chido (Ch) determinants on human C4: characterization of two C4 B5 subtypes, one of which contains Rg and Ch determinants.
abstract: The genetically determined polymorphism of the fourth component of human complement was further extended with the aid of a panel of human allo-anti-C4 sera, anti-Rodgers and anti-Chido. These antisera were found previously to react with the alpha-chains of the C4 molecules controlled by the C4A and C4B loci, respectively. We analyzed a number of new and rare C4 allotypes, and found that they generally followed the expected pattern. Some interesting exceptions, however, were found. The alpha-chain of the allotype C4A1 was found to react with anti-Chido, unlike all other C4A allotypes. Also the C4B5 allotype could be subdivided into two subtypes on the basis of their reaction with anti-Rodgers. They were tentatively named B5Rg+ and B5Rg-. Moreover, the B5Rg+ subtype reacted not only with anti-Rodgers but also with some anti-Chido sera, indicating for the first time that Chido and Rodgers determinants are present on the same allotype.
mesh_terms: D000937:Antigen-Antibody Reactions; D001789:Blood Group Antigens / Q000235:genetics* / Q000276:immunology; D003181:Complement C4 / Q000235:genetics / Q000302:isolation & purification*; D015934:Complement C4a; D015935:Complement C4b; D004591:Electrophoresis, Polyacrylamide Gel; D000939:Epitopes / Q000235:genetics*; D008040:Genetic Linkage; D006801:Humans; D011110:Polymorphism, Genetic; D011233:Precipitin Tests
chemical_list: D001789:Blood Group Antigens; D003181:Complement C4; D000939:Epitopes; D015934:Complement C4a; D015935:Complement C4b