1. Center for Perinatal Research, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio.
2. Department of Pediatrics, College of Medicine, The Ohio State University, Columbus, Ohio.
3. Department of Immunology and Infectious Diseases, Montana State University, Bozeman, Montana.
4. Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.