title: Identification of human erythrocyte blood group antigens on the C3b/C4b receptor.
abstract: The Knops/McCoy (Kn/McC) human erythrocyte blood group system belongs to the category of blood group Ag that generate so-called "high titer low avidity" antibodies in immunized transfusion recipients. Screening of red cells lacking certain high titer low avidity Ag demonstrated markedly diminished CR1 expression on McC(d-) and Kn/McC "null" (Kn(a-)McC(a-b-c-d-e-f-] erythrocytes. Additional testing by other methods confirmed these data, and biochemical assays demonstrated no detectable immunoreactive CR1 protein in membranes from Kn/McC null red cells. Human antisera to various Kn/McC Ag were then used to demonstrate that many of these antisera could be used to isolate a protein of identical m.w. to that isolated from the same cells using murine mAb CR1 antisera. Finally, protein isolated by using murine mAb anti-CR1 reacted specifically with anti-Kn/McC antibodies, demonstrating the identity of the Kn/McC and CR1 proteins. Thus, CR1 protein bears the human erythrocyte Kn/McC blood group Ag.
authors.affiliation: Department of Medicine, Duke University Medical Center, Durham, NC 27710.
authors.forename: N
authors.initials: N
authors.lastname: Rao
authors.forename: D J
authors.initials: DJ
authors.lastname: Ferguson
authors.forename: S F
authors.initials: SF
authors.lastname: Lee
authors.forename: M J
authors.initials: MJ
authors.lastname: Telen
mesh_terms: D000911:Antibodies, Monoclonal; D001789:Blood Group Antigens; D015153:Blotting, Western; D004910:Erythrocyte Membrane / Q000737:chemistry*; D004912:Erythrocytes / Q000276:immunology; D006801:Humans; D007519:Isoantigens / Q000032:analysis*; D008565:Membrane Proteins / Q000032:analysis; D011951:Receptors, Complement / Q000032:analysis* / Q000276:immunology; D017463:Receptors, Complement 3b
chemical_list: D000911:Antibodies, Monoclonal; D001789:Blood Group Antigens; D007519:Isoantigens; D008565:Membrane Proteins; D011951:Receptors, Complement; D017463:Receptors, Complement 3b