title: Genetic immunisation against hepatitis B using whole bacteriophage lambda particles.
abstract: Mice and rabbits have been vaccinated with whole bacteriophage lambda particles containing a DNA vaccine expression cassette under the control of the CMV promoter (enhanced green fluorescent protein [lambda-EGFP] or hepatitis B surface antigen [lambda-HBsAg]). Mice were vaccinated twice intramuscularly (i.m.) with 5x10(9) of lambda-EGFP phage (containing 250 ng DNA) and exhibited specific anti-EGFP responses 28 days post-vaccination. Rabbits were vaccinated i.m. with 4x10(10) of lambda-HBsAg phage (2 microg DNA) or recombinant HBsAg protein. Following two vaccinations with lambda-HBsAg, one out of four rabbits exhibited high level anti-HBsAg responses (comparable to those seen using the recombinant HBsAg protein). Following a third vaccination with lambda-HBsAg, all four rabbits showed similar high level responses which have not decreased after more than 6 months. High anti-phage responses were observed in all animals following the first immunization with lambda-HBsAg, indicating that a high antibody titre against the phage carrier did not prevent a subsequent immune response against the DNA vaccine component. Compared to results in mice using equivalent lambda-HBsAg doses, anti-HBsAg responses were much higher in rabbits, which could indicate a swamping effect in mice. Since phage lambda DNA is approximately 50 kb in size (tenfold larger than most plasmid vectors used for naked DNA immunisation), a comparable dose of phage lambda DNA given as intact phage particles actually delivers tenfold less vaccine DNA on a per gene copy (molar) basis. Thus the efficiency of the technique may be even higher than the data at first suggests.
authors.affiliation: Moredun Research Institute, International Research Centre, Pentlands Science Park, Bush Loan, Penicuik EH26 0PZ, Scotland, UK. marcj@mri.sari.ac.uk
authors.forename: John B
authors.initials: JB
authors.lastname: March
authors.forename: Jason R
authors.initials: JR
authors.lastname: Clark
authors.forename: Catherine D
authors.initials: CD
authors.lastname: Jepson
mesh_terms: D000818:Animals; D010582:Bacteriophage lambda / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D049452:Green Fluorescent Proteins; D006509:Hepatitis B / Q000517:prevention & control*; D006510:Hepatitis B Antibodies / Q000032:analysis / Q000096:biosynthesis; D006514:Hepatitis B Surface Antigens / Q000276:immunology; D017325:Hepatitis B Vaccines / Q000276:immunology*; D015151:Immunoblotting; D008164:Luminescent Proteins / Q000235:genetics; D051379:Mice; D011817:Rabbits; D019444:Vaccines, DNA / Q000276:immunology
chemical_list: D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D017325:Hepatitis B Vaccines; D008164:Luminescent Proteins; D019444:Vaccines, DNA; D049452:Green Fluorescent Proteins