Abstract
1 Animal Center for Biomedical Research, Faculty of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113, Japan
2 National Institute of Animal Health, Tsukuba, Ibaraki 305, Japan
4 Department of Veterinary Microbiology, Faculty of Agriculture, Kagoshima University, Koorimoto, Kagoshima 890, Japan
3 Scale Up Department, Genetic Therapy, Inc., Gaithersburg, Maryland 20878
5 Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892