TABLE 1.
Comparison of various methods for monitoring immune responses to the ETEC vaccine in adult Bangladeshi volunteers
| Immune parameter | CFA/I
|
CTB
|
||||
|---|---|---|---|---|---|---|
| Responder frequencya | Fold increaseb | Statistical significancec | Responder frequency | Fold increase | Statistical significance | |
| Gut ASC | 6/13 (46) | 3.7 | P = 0.006 | 8/13 (62) | 10 | P = 0.02 |
| Blood ASC | 22/27 (81) | 9.0 | P = 0.0001 | 25/27 (93) | 299 | P < 0.0001 |
| Extracted Ab | 9/13 (69) | 2.2 | P = 0.001 | 12/13 (92) | 6.2 | P < 0.01 |
| Lavage Ab | 8/14 (57) | 1.8 | NS | 13/14 (93) | 4.6 | P = 0.0001 |
| Fecal Ab | 10/18 (56) | 2.3 | NS | 14/18 (78) | 7.0 | P = 0.0005 |
a
Expressed as the number of responders/total number tested (percent responders). A vaccinee with at least a twofold increase in ASC numbers or antibody (Ab) titer was considered a responder.
b
The median postimmunization value (after two oral doses of vaccine) divided by the median preimmunization value equals the fold increase of the respective immune parameter.
c
The statistical significance of the fold increase induced by vaccination was determined by the Wilcoxon signed rank test. NS, not significant.