Project 5
Development and Application of Integrated In Vitro Cell-Based Bioassays

Michael S. Denison, Project Leader
Bruce D. Hammock, Senior Investigator
Isaac N. Pessah, Senior Investigator
Robert H. Rice, Senior Investigator

Development of rapid and inexpensive detection of specific chemicals or chemical classes in environmental and biological samples has been hampered by the lack of available specific bioassay/biomarker systems. Accordingly, the overall goals of this project are to develop and validate a series of mechanistically-based cell and in vitro bioassays/biomarkers that have application for chemical detection and screening. Since effective development and application of bioassays/biomarkers is greatly facilitated by an understanding of the specific response of a cell to a given toxicant or class of toxicants, each of the four proposed approaches will exploit information derived from an analysis of the basic molecular mechanisms by which selected chemicals affect cellular receptors, signal transduction pathways and cellular/enzyme functions. Overall, the proposed studies will not only increase our basic knowledge of the biological and toxicological effects of a variety of Superfund priority chemicals, but the resulting specific bioassays and biomarkers that will be developed will provide rapid mechanistically-based screening systems for the detection of toxicants and toxicant exposure.

I. Develop, optimize and validate a series of sensitive and rapid in vitro and cell-based vitro bioassays for detection of toxicants that exert their action via ligand-dependent nuclear receptors.

II. Develop and utilize human keratinocyte cell systems for detection and characterization of genomic, proteomic and metabolomic effects of metals/metalloids and chemicals that produce cellular oxidative stress.

III. Evaluate the influence of Superfund chemicals on the production of regulatory lipids controlling inflammation.

IV. Develop, optimize and validate rapid and sensitive cell and in vitro bioassays for detection of toxicants that affect calcium signaling pathways.

V. Integrate, validate and apply the optimized in vitro and cell bioassay systems for rapid detection and relative quantitation of target toxicants present in complex mixtures of chemicals.