FIG. 5.
Survival of infant mice following oral challenge with virulent classical V. cholerae O1 bacteria treated with anti-TcpA (toxin-coregulated pilus protein A) peptide serum. Groups of 10 4- to 5-day-old CD-1 mice were orally gavaged with 4.4 × 106 CFU of classical V. cholerae O1 Ogawa bacteria (representing 4.4 50% lethal doses) which was mixed with tertiary antisera (A and B) or preimmune antisera (C); some pups were not infected (C). Mice were kept at 30°C and monitored for death every 4 h starting 24 h after oral challenge. The protection data for anti-TcpA 15 serum are representative of seven independent challenge assays. In six independent experiments, protective efficacy ranged between 70 and 100% (mean, 91.4%) for anti-TcpA 15 serum.