[Differentiation of infection with Mycobacterium tuberculosis by recombinant Mycobacterium tuberculosis 11000 protein].

Objective: To study the differentiation effect of recombinant Mycobacterium tuberculosis 11000 protein on infection of Mycobacterium tuberculosis.

Methods: Guinea pigs were immunized with different strains of mycobacterium, and then all guinea pigs were given intradermal injections with recombinant Mycobacterium tuberculosis 11000 protein and purified protein derivative of tuberculin (PPD) or purified protein derived from M. intracellulare (PPD-B). Skin reactions defined with two transverse diameters were read double-blinded after 24 and (or) 48 hours, and the means of the two transverse diameters were counted as the reaction diameters.

Results: All guinea pigs immunized with different strains of Mycobacteria responded to PPD or PPD-B with positive skin reactions. The recombinant Mycobacterium tuberculosis 11000 protein elicited positive skin reactions in guinea pigs infected with live Mycobacterium tuberculosis, Mycobacterium bovis, Mycobacterium africanum and Mycobacterium kansasii, and the reaction diameters were (14.7 +/- 2.0) mm, (9.3 +/- 3.8) mm, (18.7 +/- 2.4) mm and (14.8 +/- 4.2) mm, respectively. But it failed to elicit positive skin reaction in guinea pigs immunized with killed Mycobacterium tuberculosis, live BCG and other MOTT (mycobacteria other than Mycobacterium tuberculosis).

Conclusions: Recombinant Mycobacterium tuberculosis 11000 protein can differentiate infection with live Mycobacterium tuberculosis from immunization with killed Mycobacterium tuberculosis, live BCG or other MOTT.