T01011: New developments of cultured precision-cut tissue slices for studies of organ pharmaco-toxicology
Thursday 23 September 2004
This research project aims to develop in vitro methodology for investigating the toxicological effects of dietary chemicals in liver and lung tissue.
Background
Previous studies to identify potentially toxic dietary chemicals in order to assess likely risks have used animal data that are subsequently extrapolated to humans. However, there is a requirement to reduce the number of animals used. An approach to minimising animal use is the application of cell-based strategies, where multiple slices of tissue from the same source are used in experimental toxicological assessments. Maximisation of source material is of particular importance given that human tissue is of limited availability. Therefore an improved method of preserving tissue to be used for in vitro screening at a later date is necessary.
Research Approach
The project aims to optimise the necessary conditions for precision-cut tissue slices to function in a state comparable to in vitro conditions for toxicological assessment. Factors perceived to affect the viability of the tissue slices include the type and composition of the gas phase and the culture medium.
Modifications of known cryogenic techniques have been performed on liver and lung tissue with the aim of preserving the cellular structure and metabolic function over an extended period.
In vitro studies with liver and lung tissue slices investigated xenobiotic metabolism and xenobiotic-induced toxicity, with particular emphasis being placed on the metabolic differences between liver and lung.
Work was performed in collaboration with six other laboratories as part of the EU Biotech program project, "Euroslices". BIBRA was to concentrate on studies on human and rat liver slices and rat lung slices.
Results and findings
This project aimed to expand upon previous experimental protocol in the cryopreservation and cell culture of rat liver and lung tissue slices for toxicological research.
Xenobiotic-induced toxicity was successfully demonstrated in tissue slices, suggesting a positive future role for the procedure in toxicological studies. When examining the metabolic differences that exist between the different tissue types, in vitro results from liver and lung tissue slices correlated well with published data from in vivo studies. Cell specific toxicity requires further study.
Cryopreservation of rat liver slices was successful, with levels of protein synthesis and potassium content at in vivo levels after preservation. An increase in the viability of this tissue was noted with an increase in dimethyl sulphoxide (DMSO) in the cryoprotectant solution. Conversely, cryopreservation of rat lung slices was less successful, with an increase in DMSO proving to be toxic to rat lung tissue, resulting in a lowered tissue viability level post-preservation.
This project has led to improvements in procedures utilising precision-cut tissue slices and has shown that in vitro toxicological screening may be a workable alternative to some larger scale animal studies. It also provides the opportunity to exploit human tissue of limited availability, removing the need to extrapolate animal data to humans, eliminating any species differences.
Dissemination information
Final report is available from the FSA Library and Information centre.
To obtain a copy, please contact the Enquiry Desk, Dr Elsie Widdowson Library and Information Services, Food Standards Agency ( tel: 020 7276 8181/8182 ) or email: library&info@foodstandards.gsi.gov.uk).
Results of this project have been published:
Price RJ, Renwick AB, Walters DG, Young PJ, Lake BG.
Metabolism of nicotine and induction of CYP1A forms in precision-cut rat liver and lung slices.
Toxicology In vitro. 2004 Apr;18(2):179-85.
Lake BG, Meredith C, Scott MP, Renwick AB, Price RJ.
Use of cultured precision-cut rat lung slices to study the in vitro induction of pulmonary cytochrome P450 forms.
Xenobiotica. 2003 Jul;33(7):691-702.
Meredith C, Scott MP, Renwick AB, Price RJ, Lake BG.
Studies on the induction of rat hepatic CYP1A, CYP2B, CYP3A and CYP4A subfamily form mRNAs in vivo and in vitro using precision-cut rat liver slices.
Xenobiotica. 2003 May;33(5):511-27.
Contact: For any enquiries concerning this research project, please contact the relevant Programme contact or email: science@foodstandards.gsi.gov.uk