Correction to: Nature Immunology https://doi.org/10.1038/ni.3790, published online 19 July 2017.

In the version of this article initially published, in the Acknowledgments, a grant number was omitted for author A.M. The correct wording is “A.M. was supported by the European Research Council (PHII, grant no. 669415), AIRC and Fondazione Cariplo.” The error has not been corrected in the original article.