TABLE 3.
Shigella antigen-specific serum IgG immune responses
| Shigella serotype | LPS multiplier | Antigen-specific serum IgG responses a | |||
|---|---|---|---|---|---|
| LPS b | InvaplexNAT | IpaB | IpaC | ||
| S. flexneri 2a | 1× | 227 ± 239 50% |
6,465 ± 4,336**** 100% |
10,263 ± 16,561**** 100% |
8,146 ± 3,155**** 100% |
| 2× | 454 ± 484*
c
66% |
5,132 ± 7,887**** 100% |
11,520 ± 34,448**** 100% |
10,263 ± 2,352**** 100% |
|
| 4× | 509 ± 436** 100% |
5,760 ± 3,935**** 100% |
16,292 ± 18,724**** 100% |
18,287 ± 5,949**** 100% |
|
| 8× | 454 ± 1,090* 50% |
9,143 ± 6,916**** 100% |
20,526 ± 31,426**** 100% |
29,029 ± 29,521**** 100% |
|
| Placebo | 90 ± 0 0% |
90 ± 0 0% |
90 ± 0 0% |
90 ± 0 0% |
|
| S. flexneri 3a | 1× | 202 ± 110 33% |
907 ± 478**** 100% |
5,760 ± 2,832**** 100% |
5,132 ± 3,155**** 100% |
| 2× | 286 ± 281* 50% |
1,143 ± 842**** 100% |
6,465 ± 7380**** 100% |
6,465 ± 2,352**** 100% |
|
| 4× | 509 ± 1,080** 67% |
1,018 ± 904**** 100% |
2,880 ± 8,597**** 100% |
7,257 ± 2,974**** 100% |
|
| 8× | 454 ± 461** 83% |
907 ± 478**** 100% |
808 ± 441**** 100% |
8,146 ± 3,155**** 100% |
|
| Placebo | 90 ± 0 0% |
90 ± 0 0% |
90 ± 0 0% |
90 ± 0 0% |
|
| S. flexneri 6 | 1× | 163 ± 237 29% |
720 ± 917**** 86% |
6,360 ± 7,138**** 100% |
14,043 ± 7,221**** 100% |
| 2× | 180 ± 231 29% |
1,070 ± 828**** 100% |
6,360 ± 3,266**** 100% |
15,505 ± 6,158**** 100% |
|
| 4× | 148 ± 243 29% |
720 ± 451**** 100% |
1,938 ± 1,699**** 100% |
12,719 ± 6,531**** 100% |
|
| 8× | 148 ± 231 14% |
1,181 ± 1,939**** 100% |
1,440 ± 1,894**** 100% |
14,043 ± 7,221**** 100% |
|
| Placebo | 90 ± 0 0% |
90 ± 0 0% |
90 ± 0 0% |
90 ± 0 0% |
|
| S. sonnei | 1× | 143 ± 105 17% |
1,616 ± 882**** 100% |
9,143 ± 35,273**** 100% |
4,572 ± 3,367**** 100% |
| 2× | 143 ± 105 17% |
1,814 ± 1,115**** 100% |
5,132 ± 3,155**** 100% |
8,146 ± 3,155**** 100% |
|
| 4× | 202 ± 135* 50% |
2,286 ± 1,683**** 100% |
8,146 ± 9,362**** 100% |
12,931 ± 15,456**** 100% |
|
| 8× | 101 ± 37 0% |
907 ± 478**** 100% |
404 ± 478* 83% |
8,146 ± 3,155**** 100% |
|
| Placebo | 90 ± 0 0% |
90 ± 0 0% |
90 ± 0 0% |
90 ± 0 0% |
|
a
Responses are shown as geometric mean endpoint titers ± standard deviation with percent responders (defined as a ≥4-fold-increase over baseline).
b
LPS responses are directed to the homologous serotype used for vaccination.
c
Significance determined by one-way ANOVA with Bonferroni post hoc test compared to placebo group *P < 0.05, **P ≤ 0.01, ***P ≤ 0.001, ****P ≤ 0.0001.