CLONING AND EXPRESSION OF A CANDIDATE MALARIAL EPITOPE IN BACILLE CALMETTE-GUERIN

The candidate malarial vaccine epitope, region II of Plasmodium falcip arum circumsporozoite protein (RII-CSP), was cloned into Mycobacterium smegmatis and M. bovis BCG via a mycobacterial replicative plasmid pU S1762. This plasmid contained a gene for the M. leprae 18 kDa protein to provide expression signals. Transformation was achieved by electrop oration and selection for kanamycin resistance and verified by Souther n hybridisation and sequencing. The transformation efficiency was in t he order of 10(4) cfu/mg DNA for M. smegmatis and 10(3) cfu/mg DNA for M. bovis BCG. Western blotting using a polyclonal antibody specific f or the RII-CSP and a monoclonal antibody specific for the M. leprae pr otein showed the expected 25 kDa band of the 18 kDa-RII-CSP fusion pro tein.