Neutralizing antibody titer and antibody response of sera from mice vaccinated with L1 or L2×8 delivered as protein or a DNA vaccine via electroporation.

<p>Balb/c mice were vaccinated three times at two week intervals with PBS, 10 µg L2×8 DNA vaccine i.m. with electroporation three times, or twice utilizing 10 µg HPV16 L1 DNA vaccine i.m. with electroporation followed by a single boost with 25 ug L2×8 protein in alum s.c., 10 µg HPV16 L1 DNA vaccine i.m. with electroporation three times, three times with 10 µg L2×8 DNA vaccine i.m., or 25 ug L2×8 protein in alum s.c., or Gardasil s.c.,,. Serum samples were collected two weeks after the third vaccination, and were tested for in vitro HPV16 neutralization titer (A) and antibody response to HPV16 L2 (B) as measured by ELISA. (C) To assess relative levels of expression, 293TT cells were transfected with no plasmid, HPV16 L1+L2 DNA in pShell, full length HPV16 L2 DNA in p16L2h, bacterial codon optimized L2×8 DNA in pcDNA, or human codon optimized L2×8 in pcDNA. 293TT cells were lysed two days after transfection. Western blotting was performed with lysate samples using a monoclonal antibody to HPV16 L2 17–36.