Development of an ELISA for vitellogenin in whole body homogenate of zebrafish (Danio rerio)

The yolk protein, lipovitellin (Lv) was purified from ovaries of mature fem ale zebrafish (Danio rerio) by gel filtration and anion exchange chromatogr aphy. Polyclonal antibodies against Lv were raised in rabbits. Anti-Lv IgG was purified by affinity chromatography. SDS-PAGE followed by Western blott ing was performed to analyse the specificity of the antibody and the immuno logical similarities between Lv and vitellogenin (Vtg). Anti-Lv IgG was use d to develop a direct non-competitive sandwich ELISA to measure Vtg concent rations of whole body homogenate (WBH) in zebrafish. The intra- and interas say variabilities were 5.8% and 10.4%, respectively. The sensitivity was 0. 2 ng Vtg ml(-1) and the practical detection limit was 40 ng Vtg g(-1) fish (wet weight). Adult male zebrafish were exposed to a nominal water concentr ation of 10 ng l(-1) of ethinylestradiol (EE,) in a semi-static exposure sy stem for 7 days. Compared with the control group, exposure to 10 ng EE2 l(- 1) induced a 200-fold increase in Vtg levels. (C) 2001 Elsevier Science Inc . All rights reserved.