# Results of an attempt to reproduce the STAP phenomenon

## TL;DR

This paper reports a failed attempt to reproduce STAP cells, which were previously claimed to gain pluripotency through a simple stimulus.

## Contribution

The study provides a direct replication attempt by the original researcher, showing no evidence of chimera formation from STAP cells.

## Key findings

- STAP cells injected into embryos did not contribute to any tissue development.
- Out of 1154 embryos, 671 were recovered but showed no significant contribution from the injected cells.
- The results contradict the original claims of STAP cell pluripotency.

## Abstract

This reports the results of an attempt by Haruko Obokata to replicate the phenomenon of stimulus-triggered acquisition of pluripotency (STAP), which was first reported in a pair of papers authored by Obokata and colleagues in 2014. The most conclusive evidence for the pluripotency of so-called STAP cells was their purported ability to contribute to chimera formation. In the follow-up trial presented here, putative STAP cells prepared by Obokata were injected into 1154 embryos, of which 671 were recovered. However, the injected cells made no significant contribution in any tissue in any of the embryos developed.