Table 1.

Immunogenicity of pcDNA3JEME in ICR mice with two immunizations

ImmunogenaRouteDose at wkbNEUT titercat wkbSurvi- vald
pcDNA3JEMEi.m.100 μg100 μg<1:101:201:6405/5
pcDNA3JEMEi.m.10 μg10 μg<1:101:101:3205/5
pcDNA3JEMEi.d.100 μg100 μg<1:101:101:1605/5
pcDNA3JEMEi.d.10 μg10 μg<1:101:201:6405/5
PBSi.m.<1:10<1:10NAe 0/5
JE virusf i.p.5 × 106PFUNone1:801:160≥1:1,2802/2
  • a Each immunogen was given to five female ICR mice at the ages indicated, and the mice were challenged at week 8.

  • b Ages of the mice at the time of inoculations or serum collections; 11 weeks indicates 3 weeks postchallenge.

  • c Represented as the serum dilution yielding a 90% reduction in plaque number.

  • d Number of surviving mice/total number of mice tested 3 weeks after challenge with 10,000 LD50 of the P3 strain of JE virus.

  • e NA, serum was not available.

  • f The immunogen given at 4 weeks consisted of the live Nakayama strain of JE virus at a dose that killed three of five mice. Therefore, all serological and challenge data were derived from the remaining two mice.