TABLE 1.
Serum neutralizing-antibody titers of immunized groups of mice
| Vaccination typea | Adjuvant | Mean log serum neutralizing-antibody titer ± SEMb (statistical group[s])c |
||
|---|---|---|---|---|
| Preimmunization | 14 days postimmunization | 5 days postchallenge | ||
| Mock | None | <3.0 | <3.0 | <3.0 |
| M-VLP | None | <3.0 | <3.0 | <3.0 |
| M-VLP | TMG | <3.0 | <3.0 | ≤3.0 |
| M-VLP | αGC | <3.0 | <3.0 | 3.6 ± 0.6 (A) |
| F-VLP | None | <3.0 | 4.0 ± 0.2 (A) | 4.3 ± 0.3 (A) |
| F-VLP | TMG | <3.0 | 6.1 ± 0.7 (B) | 9.2 ± 0.7 (A, B, C) |
| F-VLP | αGC | <3.0 | 7.7 ± 0.7 (B, C) | 7.4 ± 0.3 (C, D) |
| HMPV | None | <3.0 | 9.0 ± 0.1 (C) | 8.8 ± 0.8 (B, D) |
Mice were inoculated in the i.p. cavity with vaccine preparations on days 0 and 14, except that the HMPV group was infected i.n. on day 0.
Serum samples were collected preimmunization, 14 days after primary immunization before boost inoculation, and 5 days after HMPV i.n. infection. Titers of neutralizing antibody against HMPV were determined with an HMPV plaque reduction assay. The neutralizing-antibody titer was calculated as the antibody dilution at which the HMPV plaque number was reduced by 50%, based upon nonlinear regression analysis.
Mean antibody titers were compared by one-way ANOVA and assigned to statistically similar groups by using Tukey's multiple-comparison test. Values within a column that have a letter in common do not differ significantly (P > 0.05).