PRODUCTION OF VIBRIO-CHOLERAE GHOSTS (VCG) BY EXPRESSION OF A CLONED PHAGE LYSIS GENE - POTENTIAL FOR VACCINE DEVELOPMENT

The protein E-specific lysis mechanism of the Escherichia coli-specifi c bacteriophage PhiX174 was employed to produce Vibrio cholerae ghosts (VCG). VCG consist of both rounded and collapsed cells that have lost their cytoplasmic contents through an E-specific hole in the cell env elope. These ghosts are proposed as non-living material for immunizati on against cholera. A specific membrane anchor sequence was used to in sert the human immunodeficiency virus type 1 (HIV-1) reverse transcrip ase (RT) fusion protein into the cell envelope of v. cholerae. The ide ntity of the expression products was confirmed by Western blot analysi s employing an RT-specific monoclonal antibody. HIV-1 RT was chosen as a model for the purpose of evaluating heterologous gene expression in V. cholerae and the carrier potential of VCG. Intraperitoneal immuniz ation of mice was used to evaluate the immunogenic potential of VCG. P reliminary results showed significant seroconversions to intact whole- cell vibrio antigens in mice immunized with VCG or a heat-killed whole -cell vibrio preparation.