1. Department of Microbiology and Immunology, University of Colorado Health Sciences Center, Denver, CO 80206.
2. Department of Medicine, National Jewish Center for Immunology and Respiratory Medicine, Denver, CO 80206.
3. Division of Bacterial Diseases, Centers for Disease Control, Atlanta, GA 30333.
4. Medical Research Council Tuberculosis and Related Infections Unit, Hammersmith Hospital, London W12 OHS, United Kingdom.
5. Department of Microbiology, Colorado State University, Fort Collins, CO 80523.