Serological assay for detection of antigens sequested within immune complexes

摘要

A method for detecting an antigen present in an immune complex comprises isolating an immune complex, which contains at least one antigen and at least one antibody specific for that antigen, from a sample, then incubating the immune complex under conditions effective to dissociate the immune complex and separate the antigen from the antibody. The dissociated antigen and antibody are then reassociated, and the reassociated antigen and antibody are separated from the solution, using a binding agent on a solid phase. The presence of the antigen is then detected and optionally quantified using an antigen-specific binding reaction. A second method is provided, in which the undissociated immune complexes are bound to a solid surface through an anti-IgM antibody, then are incubated with a biotinylated extract containing an antigen specific for the immune complex antibody. The presence of the biotin molecule is detected and optional quantified using a biotin-specific binding reaction.