Session 4: Application of Molecular Biology inIn Vitro Toxicology

The implementation of molecular biology in vitro toxicology has been a challenge over the last years. The present session had the special task of discussing how this new technique could be integrated and used by toxicologists. The session consisted of five different lectures. The first lecture was an overview concerning the role of cytokines in toxicology. This lecture was followed by a discussion on the topic of how effects of xenobiotics on target cells reflect the toxicity in vivo. In the third lecture the use of gene expression pattern as molecular endpoint for mechanistic toxicity was discussed, and it was suggested that array of systems would be a valuable tool in the near future. This lecture was followed by two mechanistically related lectures dealing with lead-induced alteration of gene expression in the retina, followed by a discussion concerning mechanisms of signal transduction mediated by the dioxin receptor. These lectures demonstrated that there is a need to understand the complexity before we simplify a biological process. In summary, the session discussed future possibilities for studying toxic responses in a more mechanistically direct way and how pattern recognition of altered gene expression could be an important tool in predicting toxic phenotypic alterations.