1. Unidade dos Retrovirus e Infecções Associadas, Centro de Patogénese Molecular, Faculty of Pharmacy, University of Lisbon, Portugal
2. Unidade de Biologia Molecular e Biopatologia Experimental, iMed, Faculty of Pharmacy, University of Lisbon, Portugal
3. Department of Microbiology Immunology and Pathology, Colorado State University, Fort Collins, CO 80523, USA