We have shown in a mouse model that the mixture of anti-V.C and anti -CTB IgYs can be use to prevent or treat cholera caused by either 01 or 0139. Administration of anti-V.C Igy alone also showed some therapeutic effect, whereas anti-CTB Igy alone was not so effective. These results indicate that the elimination of the bacteria in the gut is more important that neutralization of the toxin. This seems reasonable. In the case of oral vaccination that has been tried in humans, the vaccine inducing antibodies against both bacteria and toxin is most effective.
Anti-V.C IgY was very effective for 0139 infection but was not very effective for 01 infection, The reason for this difference is not clear. The behaviors of toxin productiona and ELISA reaction were not difference between 01 and 0139 cells. Furthermore, the mice challenged with 0139 died earlier than those challenged with 01, indicating that the pathogenicity of 0139 is stronger than that of 01 in this mouse model. On the banding profile of Western blotting, however, some difference were observed. This time, we immunized hens with mixed cells of 01 and 0139. In order clarify the above-mentioned phenomena, we plan to immunize the hens with each of these cells and characterize the antibodies obtained.
The therapeutic effects in the mice were similar across the range of administration intervals, from 2 h to 8 h. The mice were challenged with huge numbers of cells this amount is speculated to cause cholera more than 60 percent of the time in humans.