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ABSTRACTProbiotic products have been shown to have beneficial effects on human hosts, but what happens in the gastrointestinal tract after its ingestion remains unclear. Our aim was to investigate the changes within the small intestines after a single intake of a fermented milk product containing a probiotic. We have periodically collected the small-intestinal fluids from the terminal ileum of seven healthy subjects for up to 7 h after ingestion by small-intestinal fluid perfusion using an endoscopic retrograde bowel insertion technique. The bacterial composition of the terminal ileum clearly revealed that the ingested probiotics (Lactobacillus caseistrain Shirota: LcS and Bifidobacterium brevestrain Yakult: BbrY) occupied the ileal microbiota for several hours, temporarily representing over 90% of the ileal microbiota in several subjects. Cultivation of ileal fluids showed that under a dramatic pH changes before reaching the terminal ileum, a certain number of the ingested bacteria survived (8.2 ± 6.4% of LcS, 7.8 ± 11.0% of BbrY). This means that more than 1 billion LcS and BbrY cells reached the terminal ileum with their colony-forming ability intact. These results indicate that there is adequate opportunity for the ingested probiotics to continuously stimulate the host cells in the small intestines. Our data suggest that probiotic fermented milk intake affects intestinal microbes and the host, explaining part of the process from the intake of probiotics to the exertion of their beneficial effects on the host.

This study investigates whether genetically modified orally administered Lactococcus lactis (L lactis) could be used as an HIV vaccine. L lactis is immunogenic and extremely safe when delivered orally. We created a recombinant L lactis vector expressing the envelope protein of HIV on its cell surface. Oral immunization with this vector induced high levels of HIV-specific serum IgG and fecal IgA antibodies. Cell-mediated immune responses also were generated in both the regional lymph nodes and the spleen. Dendritic cells are readily infected by L lactis and appear to play a potential role in mediating the development of these immune responses. The protective efficacy of this vaccine strategy was demonstrated by challenging mice intraperitoneally with an HIV Env–expressing vaccinia virus. Their viral loads were 350-fold lower than those of control mice. These findings support the further development of L lactis–based HIV vaccines. (Blood. 2003; 102:223-228)

This study investigates whether genetically modified orally administered Lactococcus lactis(L lactis) could be used as an HIV vaccine. L lactisis immunogenic and extremely safe when delivered orally. We created a recombinant L lactisvector expressing the envelope protein of HIV on its cell surface. Oral immunization with this vector induced high levels of HIV-specific serum IgG and fecal IgA antibodies. Cell-mediated immune responses also were generated in both the regional lymph nodes and the spleen. Dendritic cells are readily infected by L lactisand appear to play a potential role in mediating the development of these immune responses. The protective efficacy of this vaccine strategy was demonstrated by challenging mice intraperitoneally with an HIV Env–expressing vaccinia virus. Their viral loads were 350-fold lower than those of control mice. These findings support the further development of L lactis–based HIV vaccines. (Blood. 2003; 102:223-228)

To characterize the potential of heat killed Lactobacillus casei, Shirota strain (LC9018), as an alternative to bacillus Calmette-Guerin (BCG) for treating patients with bladder cancer we investigated the antitumor effects of intravesical instillation of LC9018 in the MBT-2 orthotopic bladder tumor implantation model in C3H/He mice.

The tufBgene encoding elongation factor Tu (EF-Tu) of Thermus thermophilusHB8 was cloned and expressed. Compared with the known tufAgene of T. thermophilus, nucleotide differences were found at 10 positions out of 1221 nucleotides, and amino acid substitutions were found at 4 positions out of 406 amino acids. The tufBproduct was 70.9% homologous to the corresponding sequence of the tufBproduct of E. coli. The G+C content of the third base of the codon in the tufBgene was 84.8% and G was especially preferred in this position.

The tufBgene encoding elongation factor Tu (EF‐Tu) of Thermus thermophilusHB8 was cloned and expressed. Compared with the known tufAgene of T. thermophilus, nucleotide differences were found at 10 positions out of 1221 nucleotides, and amino acid substitutions were found at 4 positions out of 406 amino acids. The tufBproduct was 70.9% homologous to the corresponding sequence of the tufBproduct of E. coli. The G+C content of the third base of the codon in the tufBgene was 84.8% and G was especially preferred in this position.