1. Department of Virology and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, Tennessee 381051;
2. D. I. Ivanovsky Institute of Virology, 123098 Moscow, Russia2;
3. Department of Pharmaceutical Development, Pasteur Merieux, 69280 Marcy l’Etoile, France3; and
4. Department of Pathology, University of Tennessee, Memphis, Tennessee 381634