CERVICAL SECRETIONS IN PREGNANT-WOMEN COLONIZED RECTALLY WITH GROUP-BSTREPTOCOCCI HAVE HIGH-LEVELS OF ANTIBODIES TO SEROTYPE-III POLYSACCHARIDE CAPSULAR ANTIGEN AND PROTEIN-R

Group B streptococci (GBS) colonizing the female genital tract will of ten infect newborn infants during delivery. In 200 pregnant women stud ied, 14% were colonized with GBS in the cervix, 12% in the rectum, and 9% in both cervix and rectum. We have previously reported that antibo dy levels to GBS serotypes Ia, LI, and III in sera and cervical secret ions were increased in women colonized in the rectum and/or cervix, wh en analyzed by a whole-cell ELISA. Here, we report the levels of antib odies to GBS serotype III capsular Compared to culture-negative women, the group of women colonized rectally had markedly elevated levels of immunoglobulin (Ig)A and IgG antibodies in cervical secretions to bot h CPS III and protein R-4 (P < 0.01 and P < 0.001, respectively). In s era, the corresponding differences between culture-negative and cultur e-positive women were less pronounced, or not present. In contrast to antibody levels to whole-cell GBS, antibody levels to CPS III and prot ein R-4 in cervical secretions were not significantly increased in wom en colonized only in the cervix, except that IgA antibodies to protein R-4 were slightly elevated (P < 0.05). These findings suggest that ca psular type-specific polysaccharides and protein R-4 in a mucosal vacc ine might induce protective antibodies against GBS colonization of the uterine cervix.