Biological effects of contaminants: Radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA) techniques for the measurement of marine fish vitellogenins

This document describes immunochemical methods to quantify the egg-yolk precursor protein vitellogenin in fish plasma. Vitellogenin is normally produced by the liver of mature female fish in response to 17β-oestradiol (E2) in the blood. If male or reproductively immature fish are exposed to oestrogenic substances, either in the water or the diet, their livers will also be stimulated to produce vitellogenin. Concentrations of vitellogenin in the plasma of induced and uninduced fish can differ by a factor of between 106 and 107. This makes vitellogenin induction in male and immature fish a very good biomarker for environmental oestrogens. All necessary steps in the development of both RIA (radioimmunoassay) and ELISA (enzyme-linked immunosorbent assay) are described, as are special precautions that need to be considered during the analysis of this protein.