10 Mar 2014 12:23

Riken releases details of how to generate STAP cells

TOKYO (Kyodo) -- Japan's government-backed Riken institute on Wednesday released details of how to generate STAP cells in response to growing complaints that the results of a technique described in a January paper cannot be replicated.

In the paper, Haruko Obokata at Riken's Center for Developmental Biology and her co-authors said they had discovered a technique to generate pluripotent cells by exposing mice body cells to acidic solution and named the method "stimulus-triggered acquisition of pluripotency" or STAP.

While heralding a groundbreaking new stem cell technology, the paper has raised a number of questions including complaints that the method to generate pluripotent cells, which can grow into any type of body tissue, cannot be replicated.

The details, or technical tips, written by Obokata and two other scientists, include the collection of somatic cells, their stimulation in low-pH solution and STAP cell culture.

They noted that cells from mice older than a week old "showed very poor reprogramming efficiency" and cells from male mice showed higher efficiency than those from females.

"We have reproducibly observed STAP cell conversion when proper procedures are followed in the correct sequence," they said. "We hope that these technical tips may answer many questions frequently asked about the experimental details."

Riken said it will publish an investigation report on images and other problems regarding the January paper, which experts inside and outside the institute are checking.

March 06, 2014(Mainichi Japan)