Retraction to: Nature Medicine https://doi.org/10.1038/nm1122, published online 31 October 2004.

The authors have retracted this article.

After publication, concerns were raised regarding the western blot and immunofluorescence images presented in the figures.

Specifically:

  • Fig. 1b Hypoxia + tPA +APC TUNEL image appears to have no background noise.

  • Fig. 3e and h images appear to contain inconsistent backgrounds and straight line artifacts between bands.

  • In Fig. 4e, all images appear to contain repeated features.

The corresponding author has stated that the issues in Figs. 1 and 3 may have been caused by data compression artifacts. Notably, the quantitative analysis of caspase levels presented in Fig. 3 is not based on the western blots in Fig. 3e, but on enzymatic assays, as indicated in the article. The corresponding author has also determined that the images in Fig. 4e were manipulated, but was unaware of it at the time of publication.

Tong Cheng, José A Fernández, John H Griffin and Berislav V Zlokovic agree with this retraction. The Editor has not been able to obtain current email addresses for Dong Liu, Huang Guo and Xiaomei Song.