IMMUNOLOGICAL CHARACTERIZATION OF ALPHA-ANTIGEN OF MYCOBACTERIUM-KANSASII - B-CELL EPITOPE MAPPING

Mapping of B-cell epitopes on alpha antigen of Mycobacterium kansasii (K-alpha) was carried out by using recombinant truncated K-alpha fusio n peptides. We observed that two immunodominant B-cell epitopes (amino acids 222-268 and 267-306) and one minor epitope (amino acid 249-286) were located in the C-terminal region of K-alpha. The other three min or B-cell epitopes were mapped in N-terminal (amino acids 80-98 and 99 -166) and central (amino acid 174-203) regions of K-alpha. All defined epitopes were common to Mycobacterium tuberculosis and M. kansasii. B esides these common epitopes, a region in K-alpha (amino acid 290-319) revealed different reactivities between antibodies against K-alpha an d alpha antigen of M. tuberculosis. These findings may provide a basis for development of serodiagnosis that can distinguish between M. kans asii and M. tuberculosis infections.