Antigen density in ELISA; effect on avidity dependency.
Two different densities of an antigen (bovine serum albumin, BSA) were used on paper disks is an enzyme-linked immunosorbent assay (ELISA) for chicken IgG anti-BSA antibodies. Disks of different antigen density but containing the same amount of the antigen showed a difference in immunoreactivity. Samples containing large amounts of low avidity antibodies gave higher absorbance when disks of lower antigen density were used. This phenomenon was not due to a competition between antibodies of various immunoglobulin classes. These findings may indicate that antigen density affects the sensitivity of ELISA to antibodies of various avidities.
D000818:Animals; D000906:Antibodies / Q000032:analysis; D002417:Cattle; D002645:Chickens; D004797:Enzyme-Linked Immunosorbent Assay; D007124:Immunoenzyme Techniques; D007074:Immunoglobulin G / Q000276:immunology*; D012710:Serum Albumin, Bovine / Q000276:immunology*
D000906:Antibodies; D007074:Immunoglobulin G; D012710:Serum Albumin, Bovine