1. Institute for Vision Research, University of Iowa, Iowa City, IA, USA
2. Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA, USA
3. Department of Microbiology & Immunology, Vanderbilt University Medical Center, Nashville, TN, USA
4. Department of Biomedical Engineering, College of Engineering, University of Iowa, Iowa City, IA, USA