In the latest twist in the story of STAP cells, a new kind of stem cell described in two Nature papers in January, a scientist is live-blogging his latest attempt to generate the cells. The papers described how subjecting cells from newborn mice to a mildly acidic solution turned them into pluripotent stem cells, the sought-after cells that can become all the body’s cell types. The researchers called the process “stimulus-triggered acquisition of pluripotency,” or STAP. Kenneth Ka-Ho Lee, a stem cell researcher at the Chinese University of Hong Kong, has already tried once to make the cells, following the methods published in Nature in January. That attempt failed, which Lee documented publicly on the website ResearchGate. The lack of success mirrors other reports from scientists around the world in the weeks since the papers were published, despite a more detailed set of methods posted by some of the authors on 5 March.
Observers have also found problems with some of the images in the papers, which has triggered an investigation by RIKEN, the Japanese research organization that employs several of the papers’ authors. The image problems have also prompted at least one of the authors to suggest that the papers should be retracted until the images and data can be verified.
But senior author Charles Vacanti says the image problems do not affect the validity of the results. On 20 March, he and his colleagues posted his lab’s protocol for generating STAP cells. Vacanti is an anesthesiologist and tissue engineering researcher at Brigham and Women’s Hospital and Harvard Medical School in Boston. The Vacanti lab’s technique includes what they call an “extremely important step” that was not described in the Nature paper or updated protocol published earlier: forcing the mature cells through very small pipettes for at least 25 minutes before exposing them to the acid solution.
Today, Lee posted in the comment section of his ResearchGate review that he had set up a team of four lab members to do the experiments. They have enough newborn mouse lung cells to start the protocol, they reported, and will make the pipettes the new protocol describes tomorrow. They promise frequent updates.