About the Authors

Matthew J. Pace

Affiliation Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America

Erin H. Graf

Affiliation Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America

Luis M. Agosto

Affiliation Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America

Angela M. Mexas

Affiliation Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America

Frances Male

Affiliation Department of Microbiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America

Troy Brady

Affiliation Department of Microbiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America

Frederic D. Bushman

Affiliation Department of Microbiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America

Una O'Doherty

unao@mail.med.upenn.edu

Affiliation Department of Pathology and Laboratory Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, United States of America

Competing Interests

This work was funded in part by a grant from Merck. There are no other connections (patents, consultation, products in development etc). This does not alter our adherence to all PLoS Pathogens policies on sharing data and materials.

Author Contributions

Conceived and designed the experiments: MJP LMA EHG AMM TB FDB UO. Performed the experiments: MJP LMA EHG FM TB. Analyzed the data: MJP LMA TB FDB UO. Contributed reagents/materials/analysis tools: TB FDB. Wrote the paper: MJP LMA EHG AMM TB FDB UO.