1. Institute of Immunology and Rheumatology, University of Oslo, N-0172 Oslo, Norway1;
2. Department of Clinical Sciences, London School of Hygiene and Tropical Medicine, London, United Kingdom2; and
3. Chemical Institute, Royal Veterinary and Agricultural University,3and
4. Clinical Biochemistry Department4 and
5. TB Research Unit,5 Statens Seruminstitut, Copenhagen, Denmark