title: An antibody chimera technique applied to enzyme immunoassay for human alpha-1-fetoprotein with monoclonal and polyclonal antibodies.
abstract: A 2-step enzyme immunoassay (EIA) for human alpha-1-fetoprotein (AFP) is proposed, which uses covalently coupled anti-AFP IgG and anti-horseradish peroxidase (HRP) IgG (antibody chimera) binding HRP as the marker enzyme immunologically. The use of polyclonal and monoclonal anti-AFP linked to anti-HRP antibodies was compared with a conventional 2-site binding EIA with HRP covalently bound to anti-AFP IgG. The sensitivity of the conventional EIA is increased by the use of an antibody chimera comprising a molar ratio of anti-AFP IgG: anti-HRP IgG of 1:8, especially if monoclonal antibodies are employed. This improved sensitivity may be achieved by a very simple coupling procedure without purification of conjugate and with very crude HRP preparations.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000936:Antigen-Antibody Complex / Q000378:metabolism; D001666:Binding Sites, Antibody; D000939:Epitopes; D006735:Horseradish Peroxidase / Q000276:immunology; D006801:Humans; D007124:Immunoenzyme Techniques / Q000592:standards; D007074:Immunoglobulin G / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D011817:Rabbits; D012756:Sheep; D013045:Species Specificity; D000509:alpha-Fetoproteins / Q000032:analysis / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000936:Antigen-Antibody Complex; D000939:Epitopes; D007074:Immunoglobulin G; D000509:alpha-Fetoproteins; D006735:Horseradish Peroxidase