Contrasting effects of coplanar versus non-coplanar PCB congeners on immunomodulation and CYP1A levels (determined using an adapted ELISA method) in the common sea star Asterias rubens L.

Biological effects of two structurally contrasting PCB congeners (coplanar 77 and non coplanar 153) were investigated by measuring the induction of CYP1A immunopositive protein (CYP1A IPP) in the pyloric caeca and the production of reactive oxygen species (ROS) by amoebocytes in the common sea star Asterias rubens. CYP1A IPP was quantified using a specially designed ELISA which uses competitive binding between sea stars and trout CYP1A IPPs. Only the coplanar congener had a significant effect on the two considered biological responses. Intensity of the effects was dose-dependent. However, the highest dose of PCB 77 induced a dramatic decrease of ROS production. It is concluded that coplanar PCBs straightforwardly affect key biological processes such as the immune system and mixed-function oxidase (MFO) system.