1. Department of Obstetrics and Gynecology, St. Vincent's Hospital, College of Medicine, The Catholic University of Korea, Suwon, Korea.
2. Department of Pathology, Johns Hopkins Medical Institutions, Baltimore, MD, USA.
3. Department of Obstetrics and Gynecology, Johns Hopkins Medical Institutions, Baltimore, MD, USA.
4. Department of Oncology, Johns Hopkins Medical Institutions, Baltimore, MD, USA.
5. Department of Molecular Microbiology and Immunology, Johns Hopkins Medical Institutions, Baltimore, MD, USA.