The existence of insoluble-rheumatoid factor based immune complexes in menstrual fluid

The aim of this study was to examine the existence of insoluble immune comp lexes, composed of monoclonal rheumatoid factor (human decidua-associated p rotein-hDP 200) in the precipitate of menstrual fluid. The identification o f precipitable immune aggregates was based on immunofluorescent staining an d ELISA. Both assays demonstrated the existence of rheumatoid factor, as we ll as immunoglobulins IgG, IgM, IgA and IgE. The quantification of immunogl obulins by ELISA demonstrated the predominance of IgG and rheumatoid factor . Furthermore, ELISA was performed to demonstrate the rheumatoid factor act ivity in the precipitate obtained from menstrual fluid. Thus, the rheumatoi d factor, identified by monoclonal antibody DEC 21, was demonstrated to for m precipitable immune complexes, which might provide a physiological mechan ism to remove the unnecessary antibodies formed due to fetal allograft or i ntra-uterine infection.