Induction of specific immune responses in the genital tract of women afteroral or rectal immunization and rectal boosting with Salmonella typhi Ty 21a vaccine

The purpose of this study was to determine the efficacy of intestinal tract immunization in the induction of specific antibodies in human female genit al tract secretions. Live attenuated typhoid vaccine Ty 21a was administere d to three groups of healthy female volunteers, who were not using hormonal contraceptives. Group 1 included 15 women vaccinated orally. Group 2 inclu ded seven of the same women, who were vaccinated rectally 6 months later. G roup 3 included 11 volunteers, who were vaccinated rectally. Salmonella-spe cific antibodies of IgG and IgA were measured in vaginal lavage and cervica l mucus after oral or rectal primary vaccination. Salmonella-specific antib odies measured 1 month after rectal booster vaccination demonstrated signif icant increases in vaginal fluids and cervical mucus and were dominated by IgA. These results indicate that specific antibodies in the human female ge nital tract induced by primary vaccination can be enhanced by subsequent re ctal administration of vaccines. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.