NASAL IMMUNIZATION WITH GROUP-B STREPTOCOCCI CAN INDUCE HIGH-LEVELS OF SPECIFIC IGA ANTIBODIES IN CERVICOVAGINAL SECRETIONS OF MICE

We have studied the cervicovaginal antibody responses in mice, by ELIS A, following mucosal immunizations with group B streptococci (GBS) ser otype III/R-4. Immunizations were carried out either:(1) rectally with GBS alone; (2) rectally with GBS plus cholera toxin (CT); (3) nasally with GBS alone; (4) nasally with GBS+CT; ur (5) nasally tinder genera l anesthesia with GBS+CT. Nasal immunizations with GBS alone led to at least tenfold higher levels of specific IgA-antibodies to GBS in cerv icovaginal secretions than with any other immunization. These mucosal antibody levels were higher than after rectal immunizations, and 2-17 times higher than the corresponding IgA antibody levels in sera. Marke dly lower cervicovaginal antibody levels were found in mice which had received GBS together with CT as a mucosal adjuvant than in mice immun ized by the same routes with GBS alone, Our observations indicate that a nasal vaccine consisting of GBS might induce sufficient antibody le vels to protect against genital colonization of these bacteria. (C) 19 97 Elsevier Science Ltd.