1. Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
2. Institute of Infection, Inflammation, and Immunity, University of Pittsburgh Medical Center Children’s Hospital of Pittsburgh, Pittsburgh, Pennsylvania, USA
3. Department of Pediatrics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
4. Cell Structure Laboratory, National Center for Biotechnology, CNB-CSIC, Madrid, Spain
5. Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA