TABLE 3.
Serum and stool antibody responses after challenge with wild-type EPEC strain E2348/69 or an isogenic ΔespB mutant strain (UMD864)
| Antibody group and parameter | Results for:
|
Pb | |
|---|---|---|---|
| Recipients of wild-type EPEC | Recipients of ΔespB mutant EPEC | ||
| Serum IgA anti-EspB | |||
| Response ratea (%) | 2/10 (20) | 0/10 | NS* |
| Peak GMTd among responders | 400 | NS† | |
| Serum IgG anti-EspB | |||
| Response rate (%) | 1/10 (10) | 1/10 (10) | NS |
| Peak GMT among responders | 400 | 800 | NS |
| Serum IgA anti-O127 LPS | |||
| Response rate (%) | 10/10 (100) | 5/10 (50) | 0.02 |
| Peak GMT among responders | 1,393 | 264 | <0.01 |
| Serum IgG anti-O127 LPS | |||
| Response rate (%) | 9/10 (90) | 2/10 (20) | <0.01 |
| Peak GMT among responders | 1,089 | 800 | NS |
| Serum IgA anti-whole wild-type cells | |||
| Response rate (%) | 10/10 (100) | 4/10 (40) | <0.01 |
| Peak GMT among responders | 3,200 | 476 | 0.01 |
| Serum IgG anti-whole wild-type cells | |||
| Response rate (%) | 5/10 (50) | 2/10 (20) | NS |
| Peak GMT among responders | 1,838 | 6,400 | NS |
| Stool sIgA anti-EspB | |||
| Response rate (%) | 4/8c (50) | 4/7c (57) | NS |
| Peak GMT among responders | 3.4 | 3.4 | NS |
| Stool sIgA anti-O127 | |||
| Response rate (%) | 7/8 (88) | 3/7 (43) | NS |
| Geometric mean and (ng/ml) among responders | 39 | 8 | 0.01 |
a
Number of individuals affected/total number.
b
∗, Fisher's exact test; †, Student's t test, two-tailed. NS, not significant.
c
Sample was not of sufficient quantity to assay some of the volunteers.
d
GMT, geometric mean titer.