Aastrom Biosciences Inc. on Monday said it uses adult, not embryonic, stem cells to produce cells that are being tested to see if they can repair severe bone fractures.The company’s stock fell 77 cents, or more than 19 percent, to close at $3.23 on Nasdaq after an article on Sunday in the journal Nature Medicine said batches of human embryonic stem cells available under the strict policies of the U.S. government are contaminated with an animal molecule.In a release, the Ann Arbor, Michigan-based company said it does not use embryonic stem cells, nor does it use mouse-derived feeder cells to support stem-cell growth, the two major topics of the article.Aastrom said it uses proprietary technology to produce tissue repair cells, which are an adult, patient-derived bone marrow stem and progenitor cell mixture.
