THE IMMUNOGENICITY OF RECOMBINANT MYCOBACTERIUM-SMEGMATIS BEARING BCGGENES

Specific pathogen-free C57BL/6 mice infected with recombinant Mycobact erium smegmatis (rM. smegmatis) bearing BCC genes showed increased spl enic survival compared to those receiving the vector control (plasmid DNA only). The mouse-passaged rM. smegmatis (J3R) survived in peritone al macrophages better than the vector control, regardless of whether t he macrophages were infected in vivo or in vitro, When rM. smegmatis J 3R was cultured in synthetic Proskauer-Beck-Tween medium, protein band s characteristic of BCG culture filtrates and not present in the vecto r control preparation were observed, Mice immunized with two doses of heat-killed J3R suspended in Freund's adjuvant were able to limit the growth of virulent Mycobacterium tuberculosis within the lung and sple en compared to that observed in control mice receiving adjuvanted vect or control or Freund's adjuvant alone.