In addition to the goal of using pluripotent stem cells in regenerative medicine, The Economist writes that drug companies are also interested in using them to test drugs. Pluripotent stem cells could be used to generate "pure cultures of cells," The Economist says. And it adds that are already moving in that direction as AstraZeneca has announced that it plans to buy cell lines derived using iPS cells from Cellular Dynamics, a company founded by stem cell pioneer James Thomson, to test toxicity of new drugs, and GlaxoSmithKline has used iPS cells to study potential Alzheimer's disease drugs. Others are using iPS cells to create disease models. "Several groups of researchers have used disease-prone cells created in this way to explore how the disease in question develops, and whether it succumbs to drugs," The Economist writes.