A number of alternatives are already on the market, and still more are being developed. These include such products as artificial skin to measure irritancy and toxicity of various substances; a silicon microphysiometer, which measures individual cells' responses to physical and chemical stimuli; and even cultured organ systems, being developed to examine systemic reactions to substances.
Two widely used tests illustrate that replacements for laboratory animals, or at least ways to minimize harm to them, were being sought before the animal rights movement began to receive media attention. A generation ago, a rabbit died for every human pregnancy officially diagnosed. Then, in the 1970s, monoclonal antibodies against human chorionic gonadotropin, the so-called pregnancy hormone, were developed. This approach required nurturing hybridoma cells in mouse abdominal fluid, resulting in the sacrifice of a much smaller number of animals as compared to the rabbit method. Monoclonal antibodies can now be mass-produced in ...
