DEVELOPMENT OF A SENSITIVE SANDWICH ENZYME-LINKED-IMMUNOSORBENT-ASSAY(ELISA) FOR VITELLOGENIN IN THE JAPANESE EEL ANGUILLA-JAPONICA

A specific and sensitive enzyme-linked immunosorbent assay (ELISA) was developed for the measurement of low levels of serum vitellogenin (VT G) of the Japanese eel Anguilla japonica. The non-competitive avidin-b iotm interaction was performed by a sandwich method using the specific ity of the specific antiserum to eel yolk protein (a-lipovitellin) and biotinylated F(ab')(2) fragment of a-lipovitellin. The assay could be run in 2 days and routinely detect VTG in a concentration as low as 0 .8 ng/ml. The appearance of low levels of serum VTG significantly incr eased 9-12 h after a single injection of estradiol-17 beta into immatu re fish. The development of an ELISA for VTG made possible the quantif ication of serum VTG and thereby in vitro analysis of the mechanism of the onset and course of vitellogenesis.