StemCells, Inc. (Nasdaq:STEM) announced today that its technology was recently used by independent researchers to achieve the first genetically engineered rat derived from rat embryonic stem (ES) cells. This breakthrough, published this month in the international peer-reviewed journal Nature, opens the door to the types of genetic manipulations previously only possible in mice, and paves the way for modeling a broader range of human diseases with the rat. Both mice and rats are used as animal models of human disease; however certain aspects of the rat's physiology, behavior, and metabolism are closer to the human, making rats the preferred species for drug development and studying human disease. The creation of this first rat model using rat ES cells validates intellectual property owned by StemCells, which includes the rights to patents covering both rat ES and rat induced pluripotent stem (iPS) cells as well as genetically engineered rats derived from these cells.
StemCells' broad rat pluripotent stem cell intellectual property portfolio is based upon groundbreaking research led by prominent academic researchers at the University of Edinburgh, including Dr. Qi-Long Ying who was the first to succeed in deriving and culturing the true germline competent rat ES cells required for precise genetic engineering. In this newly published study, Dr. Qi-Long Ying and his colleagues at the Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research at the University of Southern California demonstrated for the first time the creation of genetically modified rats using rat ES cells that have been gene targeted via homologous recombination, a method which involves adding DNA sequences to the cells to delete ('knock-out'), add ('knock-in') or otherwise modify genes of interest. This latest work resulted in the successful generation of knock-out rats missing the tumor suppressor gene p53 for use in studying cancer, and serves as a proof-of-principle for creating genetically engineered rats using rat ES cells.