When I mention that I am against animal experimentation, the reaction is often: “Would you prefer these tests were done on humans?” In the discussion that follows it turns out that most people don’t know that there are better and less cruel ways of doing biomedical research. Some people suggest that these alternatives, such as computer-based methods, can never be as adequate as a living animal.
However, over the last decade science has made much progress in developing non-animal methods and tools to use in basic and applied research, and for regulatory testing such as the testing of new drugs and chemicals. Governments are now encouraging and mandating researchers to use these new methods instead of live animals. For example, earlier this year 16 federal agencies in the US developed a Roadmap to guide progress toward replacing animal use in toxicity testing.
The roadmap was developed to guide the application of new technologies, such as high-throughput screening, tissue chips, and computational models, to toxicity testing of chemicals and medical products.
What exactly are these new technologies? An open access article published last year by Mary T. McBride – Future platforms for toxicity testing – provides a good summary of current and future methods for toxicity testing without animals:
- In vitro model systems, using cells and cell cultures, such as stem cells, tissue engineering and organs-on-chips, with a human-on-a-chip being under development.
- In vitro pathway-based assays and quantitative high-throughput screening (HTS). The latter employs liquid robotics handling systems and computerised data processing, to screen a single compound against a large number of assays to identify toxicity pathways or to test a large number of compounds using a single assay.
- Cell-based imaging technologies and high-content screening, using imaging tools such as innovative microscopy methods, ultrasound, Computed Tomography (CT), Magnetic Resonance Imaging (MRI), and Positron Emission Tomography (PET).
- Omics approaches, such as genomics, transcriptomics (a microarray technology to establish human genome-wide gene expression profiles by measuring all of the approximately 100,000 mRNA molecules or ‘transcripts’ produced in a cell or a population of cells), proteomics (the comprehensive study of the entire complement of proteins and their modifications of an organism to understand cellular processes) and metabolomics (the study of metabolites, such as lipids and proteins, and used to identify all of the metabolites present in a given cell or organism at a specific time).
- Data integration analysis and interpretation: bioinformatics and visualisation tools. This involves combining data from different platforms and assays across multiple experiments.
- Computational toxicology, which includes the integration of mathematical and computer models to map, model and understand the biological circuitry of toxicity pathways to predict the toxicity of environmental chemicals and pharmaceuticals and their dose-response relationships.
Tissue engineering has made tremendous advancement in the field of tissue-engineered preclinical models. Such models now exist for many whole tissues including skin, muscle, cartilage, blood vessels, bone, bladder, liver, cornea, reproductive tissues, adipose, small intestine, neural tissues, kidney and cardiopulmonary systems.
McBride suggested that “the new approach may significantly reduce costs and time required to conduct chemical safety assessments and could markedly diminish and potentially eliminate animal testing.” She pointed out that this is not an exhaustive list, and that rapid advances in biology and biotechnology are continuously emerging.
Various databases listing resources for non-animal research are available to researchers and the general public, for example ALTBIB (Resources for Alternatives to the Use of Live Vertebrates in Biomedical Research and Testing) and EURL ECVAM (European Union Reference Laboratory for alternatives to animal testing).
So no, the often cruel and painful experiments currently conducted on live animals don’t need to be done on humans. Nor do they need to be done on animals.