Table 1.

Comparison of various methods for monitoring immune responses to the ETEC vaccine in adult Bangladeshi volunteers

Immune parameterCFA/ICTB
Responder frequencyaFold increasebStatistical significancecResponder frequencyFold increaseStatistical significance
Gut ASC6/13 (46)3.7 P = 0.0068/13 (62)10 P = 0.02
Blood ASC22/27 (81)9.0 P = 0.000125/27 (93)299 P < 0.0001
Extracted Ab9/13 (69)2.2 P = 0.00112/13 (92)6.2 P < 0.01
Lavage Ab8/14 (57)1.8NS13/14 (93)4.6 P = 0.0001
Fecal Ab10/18 (56)2.3NS14/18 (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.