1. Institute for Research in Biomedicine, 6500 Bellinzona, Switzerland.
2. Humabs BioMed SA, 6500 Bellinzona, Switzerland.
3. Medical Research Council (MRC) National Institute for Medical Research, The Ridgeway, Mill Hill, London NW7 1AA, UK.
4. Viral Pseudotype Unit, School of Pharmacy, University of Kent, Kent ME4 4TB, UK.
5. Pepscan Therapeutics BV, Lelystad, 8243 RC, Netherlands.
6. Institute of Microbiology, Eidgenössische Technische Hochschule (ETH) Zürich, 8032 Zürich, Switzerland.