Detection of circulating Yersinia-immunoglobulin complexes by enzyme immunoassay (EIA)

An enzyme immunoassay (EIA) was developed for the detection of Yersinia-immunoglobulin complexes of known Ig class. Immune complexes (ICs) were attached to polystyrene microtiter plates by rabbit anti-human immunoglobulins, and the existence of Yersinia enterocolitica O:3 antigens was demonstrated using Fab fragments of alkaline phosphatase (AP)-conjugated antibody against the same serotype. Simultaneous binding of Yersinia antigens and immunoglobulins was a prerequisite for the detection of ICs. The method will be valuable for research into the immunopathogenetic mechanisms leading to reactive arthritis after Yersinia infection.