1. Department of Virology and Immunology and Southwest National Primate Research Center, Southwest Foundation for Biomedical Research, San Antonio, TX 78227, USA.
2. Santaris Pharma, Kogle Allé 6, DK-2970 Hørsholm, Denmark.
3. Copenhagen Institute of Technology, Aalborg University, Lautrupvang 15, DK-2750 Ballerup, Denmark.