Table 1.
LPS-specific systemic and mucosal immune responses either pre- or post-challenge in vaccinated and placebo subjects grouped by consensus shigellosis outcome.
| Immune Parameter | Vaccinees (n = 30) |
Placebos (n = 29) |
||||
|---|---|---|---|---|---|---|
| No Shigellosis (n = 19) | Shigellosis (n = 11) | P-Valueb | No Shigellosis (n = 12) | Shigellosis (n = 17) | P-Valueb | |
| Serum IgG | ||||||
| Pre-Challenge | 51,200a (24,879 – 105,367) | 9341 (4129 – 21,129) | 0.003 | 2263 (1309 – 3912) | 2043 (1089 – 3834) | 0.806 |
| Post-Challenge | 51,200 (29,018 – 90,340) | 8770 (4346 – 17,697) | 0.0003 | 3200 (1881 – 5443) | 5220 (3328 – 8187) | 0.143 |
| Serum IgA | ||||||
| Pre-Challenge | 3442 (2044 – 5796) | 907 (368 – 2240) | 0.006 | 212 (112 – 400) | 192 (103 – 358) | 0.819 |
| Post-Challenge | 2479 (1503 – 4089) | 1244 (771 – 2006) | 0.062 | 504 (254 – 1000) | 1109 (568 – 2162) | 0.097 |
| Serum IgM | ||||||
| Pre-Challenge | 1111 (672 – 1836) | 705 (335 – 1486) | 0.271 | 635 (328 – 1228) | 452 (240 – 851) | 0.443 |
| Post-Challenge | 800 (553 – 1157) | 662 (353 – 1241) | 0.553 | 898 (550 – 1467) | 766 (459 – 1280) | 0.643 |
| Serum IgG1 | ||||||
| Pre-Challenge | 215 (122 – 379) | 69 (44 – 106) | 0.006 | 56 (47 – 67) | 57 (44 – 73) | 0.963 |
| Post-Challenge | 155 (94 – 256) | 69 (44 – 106) | 0.026 | 59 (45 – 78) | 62 (50 – 78) | 0.791 |
| Serum IgG2 | ||||||
| Pre-Challenge | 1992 (1050 – 3778) | 662 (331 – 1325) | 0.025 | 168 (87 – 323) | 226 (123 – 415) | 0.491 |
| Post-Challenge | 2390 (1308 – 4368) | 852 (386 – 1881) | 0.035 | 283 (132 – 606) | 617 (395 – 962) | 0.053 |
| Pre-Challenge | 8076 (5050 – 12,915) | 3319 (1223 – 9009) | 0.057 | 884 (447 – 1746) | 872 (358 – 2126) | 0.982 |
| Post-Challenge | 6689 (3703 – 12,084) | 4437 (1676 – 11,743) | 0.415 | 1947 (974 – 3893) | 4564 (2315 – 8999) | 0.078 |
| α4β7+ ALS IgG | ||||||
| Pre-Challenge (Day 7 Titer) | 10 (4 – 25) | 2 (1 – 4) | 0.010 | 1 (1 – 2) | 1 (1 – 2) | 0.542 |
| Post-Challenge | 2 (1 – 4) | 3 (2 – 6) | 0.406 | 4 (1 – 12) | 28 (9 – 89) | 0.014 |
| α4β7- ALS IgG | ||||||
| Pre-Challenge (Day 7 Titer) | 13 (5 – 34) | 2 (1 – 6) | 0.016 | 1 (1 – 1) | 1 (1 – 1) | 0.164 |
| Post-Challenge | 2 (1 – 3) | 1 (1 – 1) | 0.010 | 1 (1 – 2) | 3 (2 – 6) | 0.008 |
| α4β7+ ALS IgA | ||||||
| Pre-Challenge (Day 7 Titer) | 5 (2 – 11) | 2 (1 – 5) | 0.128 | 1 (1 – 1) | 1 (1 – 1) | 0.799 |
| Post-Challenge | 1 (1 – 2) | 4 (2 – 11) | 0.037 | 4 (1 – 14) | 27 (7 – 99) | 0.034 |
| α4β7- ALS IgA | ||||||
| Pre-Challenge (Day 7 Titer) | 3 (1 – 6) | 1 (1 – 2) | 0.064 | 1 (1 – 1) | 1 (1 – 1) | – |
| Post-Challenge | 1 (1 – 2) | 1 (1 – 2) | 0.410 | 1 (1 – 1) | 1 (1 – 3) | 0.068 |
Serum IgG3 and serum IgG4 not included due to low/undetectable responses.
Memory B cell IgG and IgA responses due to the low number of subjects/timepoints used in the analysis.
a
Geometric Mean Titer (95% Confidence Interval).
b
Significance comparing peak/maximal titer either pre- or post-challenge in vaccinated subjects or placebo recipients grouped by consensus shigellosis outcome. P-value determined by T-test of log-transformed titers.