IMPROVED IMMUNOGENICITY OF ORAL DXRRV REASSORTANT ROTAVIRUS VACCINE BY LACTOBACILLUS-CASEI GG

In a search for new strategies to improve oral vaccination, the effect of orally administered Lactobacillus casei strain GG (LGG) in conjunc tion with DxRRV rhesus-human reassortant live oral rotavirus vaccine w as tested in 2-5-month-old infants. Infants who received LGG showed an increased response with regard to rotavirus-specific IgM secreting ce lls, measured using an ELISPOT technique, on day 8 after vaccination. In infants receiving LGG or placebo, respectively, a rotavirus IgM ser oconversion was dectected in 26/27 (96%) versus 23/27 (85%) cases (p=0 .15) and rotavirus IgA seroconversion was detected in 26/28 (93%) vers us 20/27 (74%) cases (p=0.05). These findings suggest that LGG has an immunostimulating effect on oral rotavirus vaccination. The clinical s ignificance of LGG-enhanced immune responses to oral vaccines should b e further evaluated.