ANTIBODY AGAINST THE CAPSULE OF VIBRIO-CHOLERAE O139 PROTECTS AGAINSTEXPERIMENTAL CHALLENGE

Antiserum to the capsular polysaccharide of an opaque variant of Vibri o cholerae O139 strain MDO-12 recognizes capsular antigen in three dif ferent colonial variants of the strain, although the amount of recogni tion varies with the extent of opacity. The anti-capsular-polysacchari de serum, at subagglutinating doses, protected suckling mice against c hallenge with both the most opaque variant and the most translucent va riant. Further studies indicated that the protection was associated wi th inhibition of intestinal colonization by the vibrios. These results thus highlight the potential importance of the capsule in immunoproph ylaxis against cholera caused by V. cholerae O139.