1. Departments of Experimental Medicine and of Microbiology and Immunology, McGill University, Montréal, Québec, Canada H3A 2B4.
2. Centre for the Study of Host Resistance and the Research Institute of the McGill University Health Centre, Montréal, Québec, Canada H3G 1A4.
3. Department of Biochemistry, McGill University, Montréal, Québec, Canada H3G 1Y6.
4. Department of Medical Genetics, University of British Columbia, Vancouver Hospital, 2660 Oak Street, Vancouver, British Columbia, Canada V6H 3Z6.