- Overall project objective
The overall aim of DETECTIVE is to identify, develop and evaluate relevant biomarkers and surrogate endpoints in vitro that can be used for safety assessments and repeated dose toxicity testing relevant for humans. A biomarker is defined as “a characteristic that is objectively measured and evaluated as an indicator of normal biologic processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention.”
- Project approach
Specifically, the DETECTIVE project will develop biomarkers of human toxicity in human-based in vitro systems by:
1. Interfacing with the other building blocks (NOTOX, COSMOS, DETECTIVE, ToxBank, HemiBio, and Scr&TOX), in particular ToxBank (building block 6), of the Alternative Testing Cluster to substantiate knowledge and toxicological data about already existing biomarkers for chronic organ damage such as arrhythmias, liver cirrhosis etc. and relevant biological processes.
2. Assessing, in collaboration with ToxBank, the suitability and robustness of existing cell lines for use in developing biomarkers for repeated dose toxicity testing in vitro.
3. Developing functional readouts in human in vitro model systems mainly for liver, heart and kidney but possibly, also for other model systems as provided by other building blocks. These functional parameters include i) electrical activity (ECG-like, MEA), ii) impedance measurements, iii) imaging, and iv) cell-specific functional readouts such as enzyme activities, cytokine release, albumin and urea secretion, glycogen uptake, cholestasis, steatosis, and protein release from target cells.
4. Developing “-omics” readouts in human in vitro model systems for liver and heart but possibly also for other model systems as provided by other building blocks. These “-omics” readouts include i) integrative transcriptomics (microarrays for global screening of gene expression, epigenetics, and miRNA), ii) proteomics, and iii) metabonomics
- Project workplan phases
The DETECTIVE work plan is divided into different phases according to the availability of test substances and cell systems and to the readout systems used. These will have impact on the type of data analysis to be carried out.
The consortium will begin work with the cell systems currently in use within the consortium (heart, liver and kidney). Quality control of the applicability of these cell systems will be carried out in the first months (WP2), using both functional and “-omics” readouts which will provide more insights into the physiological quality of the cell systems used as well as their suitability to detect repeated dose toxicological modification. Once additional cell systems and organ-simulating devices become available from building blocks 1 and 2, the consortium will start using also these cell systems after successful quality control of robustness and reproducibility. Relevant test substances will be selected by the consortium from the substance library provided by building block 6. For the development of biomarkers, functional readouts (SP2) will be used throughout the entire
duration of the project. For budgetary reasons, besides their role for quality control, the more costly “- omics” technologies (SP3) will be used in the beginning only for investigating basic questions (e.g. can we recognise repeated dose toxicity by identifying initial steps of a cellular signalling cascade?). Once the consortium can benefit from stable cell systems and organ-simulating devices provided by building blocks 1 and 2, the “-omics” technologies will be fully applied to generate comprehensive data for selected compounds and exposure protocols until the end of year 4 to leave sufficient time for thorough data analysis, which is carried out throughout the project (SP4). Functional readouts will be used also in the last year of the project to relate the results of the “-omics” readouts to the physiological status of the cells to aid qualification of “-omics” markers. Stabilisation, selection of final biomarkers and verification of those in another laboratory or using a second method will be made in the last project year (WP15).