Establishing scientific confidence in a two-chamber co-culture system to evaluate androgenic response in the presence of hepatic metabolism

For the in vitro determination of toxicity on target organs in the presence of physiologically relevant human metabolism, we recently developed a two-chamber liver-target organ co-culture system in a medium-throughput 96-well format. Our proof-of-concept study using human HepaRG microtissues cultured in three-dimension (3D) and AR-CALUX reporter cells demonstrated the significantly reduced testosterone (T)-mediated androgen receptor (AR) responses in the presence of human liver metabolism. The present study further increased the scientific confidence in this two-chamber co-culture system as a flexible and robust tool to capture androgen-mediated responses by incorporating alternate AR reporter cell systems as the target and examining additional androgenic compounds. The system generated concordant metabolism-dependent changes in T- and 5α-dihydrotestosterone (DHT)-mediated AR responses using two different AR reporter cell systems (AR-CALUX, AR-INDIGO). The AR reporters had different sensitivity ranges and required media optimization. We demonstrated that this two-chamber co-culture system with integrated hepatic biotransformation can be used to evaluate endocrine activity with potential metabolism modulation of parent compounds.