Abstract
1 Division of Virology, National Institute for Biological Standards and Control, Blanche Lane, South Mimms, Potters Bar, Hertfordshire, EN6 3QG, UK
2 Blood Systems Research Institute, San Francisco, CA 94118, USA
3 University of California, San Francisco, CA 94118, USA
4 Department of Virology, University College London Hospital, The Windeyer Building, 46 Cleveland Street, London W1T 4JF, UK
5 Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, University of Amsterdam, 1105AZ Amsterdam, The Netherlands
6 Laboratory of Immunochemistry, D. I. Ivanovsky Institute of Virology, 123098 Moscow, Russia