Landmark Pluripotent Patent Has Stem Cell Researchers Nervous

In what may presage an intellectual property battle, Rudolf Jaenisch of the Massachusetts Institute of Technology in Cambridge and Konrad Hochedlinger of Massachusetts General Hospital in Boston will be awarded a patent on a technique for turning adult mammalian cells into stem cells that can in principle become any kind of cell in the body. The approach—reprogramming somatic cells—promises to be a boon for regenerative medicine. But other groups have similar patent claims pending, and some researchers worry that a tangle of patents could delay medical applications.

The pending award of the patent was announced on 4 February by Fate Therapeutics, a San Diego-based company that Jaenisch and others founded in 2007. The November 2003 application describes a possible approach to somatic cell reprogramming. "With its early priority dates and territory reach, the Jaenisch portfolio is formidable," Paul Grayson, president of Fate Therapeutics, said in a press release. Fate "is counting on this patent to raise funding, so they will be relentless" in pushing their claims, says stem cell researcher Jeanne Loring of the Scripps Research Institute in San Diego. "It's the nature of the biotech business."

But the patent application contains no experimental results. In 2006, Kyoto University’s Shinya Yamanaka reported for the first time creating what he called induced pluripotent stem (iPS) cells by triggering mouse skin cells to revert to an undifferentiated state of pluripotency. In 2007, Yamanaka and James Thomson of the University of Wisconsin, Madison, simultaneously duplicated the feat using human cells. In response to a query from Science, Kyoto University's Center for iPS Cell Research and Application, which Yamanaka directs, issued a statement that reads in part: "Our university filed the world's first patent application associated with iPS [cell] technology and is now trying to acquire patent rights in many countries, including the U.S. We believe that the Fate Therapeutics patent will not affect our patent applications.''

In an e-mail to Science, Fate Therapeutics spokesperson Jessica Yingling wrote that the company was not yet disclosing conditions for possible licensing of its patent. "But we want to reinforce that we do not want to impede progress but work with all involved to spur innovation and the translation of iPS cell technology to new tools for the industry and therapies for patients in need."

Since Yamanaka's breakthrough, dozens of groups have reported other ways of reprogramming cells as well as techniques to control differentiation of stem cells into neurons, cardiovascular cells, and other tissues of interest for regenerative medicine. The U.S. patent office's database has more than 200 applications that mention somatic cell reprogramming. "I expect cross-licensing and, hopefully, some of the patent owners will insist as part of their agreements that the patents be widely, inexpensively, and nonexclusively licensed," says Loring.