WP2: Alternative in-vitro testing approaches for commercialised GM food/feed
There are policy moves within the EU to replace or reduce the number of animal tests for various ethical and animal welfare reasons. This contrasts with the increasing demand for more animal feeding studies to approve GM crops. GRACE will explore options for using in-vitro studies as an alternative approach for the food and feed safety assessment of GM plants. In addition to reducing animal use, the application of in-vitro cell culture systems for the safety evaluation of GM food may have further advantages, such as delivering sufficient results quickly at low cost.
The main in-vitro methods that will be investigated in the course of WP2 are:
1. molecular “omic” approaches (transcriptome, proteome, metabolome analysis)
- for comparing GM crop plant material with conventional counterparts to detect unintended effects
- for investigating e.g. intestinal, liver and immune tissues of animals used in rodent feeding trials to identify changes in gene activity and in metabolic activity in cells and tissues following exposure to GM plant components.
2. in-vitro assay systems to screen for unintended GM effects of whole GM plants, of extracts from GM plants or of newly expressed proteins from GM plants
- using primary cells (intestinal and immune cells) from farm animals and
- permanent cell lines (intestinal, reproductive and immune cells) from rodents
The molecular “omic” approaches enable a more complete, comparative analysis so that minute changes can be detected before morphological changes occur. Changes in molecular pathways that lead to toxic effects can be identified that may otherwise remain undetected.
The advantage of in-vitro assay systems using primary cells from farm animals lies in the similarity between the cells and the original organ. Such systems allow the detection of effects comparable to in-vivo physiological reactions and the results may be seen as essentially comparable to in-vivo results. However, cell systems from farm animal tissues are rarely available and are less stable.
In contrast, permanent cell lines are well established and validated though such test systems are more artificial in relation to really exposed tissues.
Outcomes will be discussed with external experts to provide recommendations on how in vitro approaches can help promote further systematic implementation of the principles of humane experimental research: replacing animals, reducing animal numbers and refining procedures to minimise suffering.
The database CADIMA (Central Access Database for Impact Assessment of Crop Genetic Improvement Technologies) contains quality assessed studies and conclusions on the health effects, socio-economic consequences and environmental impacts of GM plants as well as raw data of animal feeding studies and alternative in vitro approaches.