1. Department of Pediatrics, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
2. Division of Microbiology and Infectious Diseases, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
3. Division of Bioinformatics, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
4. University of California, San Diego, California, USA