Table 4.

Cross-reactivity of IgG in serum and IgA in tears and cross-agglutination of immune sera to various S. flexneri serotypes after immunization with an S. flexneri 2a/3a (CVD 1207/CVD 1211) combination vaccine

Immuni-zationLPS testedCross-reacting O antigensLPS cross-reactivity
IgG GMTaIgA GMTAggluti-nationb
Vaccine2aII; 3,45361,9021:16
Placebo2aNone1546
Vaccine3aIII; 6,7,82208,4581:16
Placebo3aNone1520
Vaccine1a3,45797021:2 
Placebo1aNone12.540
VaccineY3,4641,6401:4 
PlaceboYNone12.520
Vaccine1b65201,7241:4 
Placebo1bNone2526
Vaccine4b6441,7691:4 
Placebo4bNone1520
Vaccine2bII; 7,8508841:4 
Placebo2bNone2720
Vaccine5b7,8291,345Neat
Placebo5bNone12.520
Vaccine6None15145
Placebo6None12.520
  • a GMT, geometric mean titer.

  • b Pool of serum dilution that produced slide agglutination. −, Negative slide agglutination with neat antiserum.