@article{stoeker_nordone_gunderson_zhang_kajikawa_lavoy_miller_klaenhammer_dean_2011, title={Assessment of Lactobacillus gasseri as a Candidate Oral Vaccine Vector}, volume={18}, ISSN={["1556-6811"]}, DOI={10.1128/cvi.05277-11}, abstractNote={ABSTRACTLactobacillusspecies are commensal bacteria that have long been recognized as probiotic microbes and are generally regarded as safe (GRAS) for human consumption. We have investigated the use ofL. gasserias a vaccine vector for oral immunization against mucosal pathogens. Recent research has shown that the immune response to different lactobacilli can vary widely depending on the species or subspecies ofLactobacillusbeing studied. While some lactobacilli seem to induce oral tolerance, others induce an adaptive immune response. This study characterized the systemic and mucosal immune response to wild-type and genetically modifiedL. gasseri. L. gasseriprimarily activates TLR2/6, with additional activation through the TLR2 homodimer. To expand the Toll-like receptor (TLR) activation profile ofL. gasseriand the immunogenicity of the vector, a plasmid containingfliC, the gene encoding bacterial flagellin, was introduced which resulted in the strong activation of TLR5. The treatment of human myeloid dendritic cells with recombinant lactobacilli expressing flagellin triggered phenotypic maturation and the release of proinflammatory cytokines. In contrast, bacterial treatment also resulted in a statistically significant increase in IL-10 production.In vivostudies established that treatment withL. gasseriled to a diversification of B-cell populations in the lamina propria of the murine colon. Furthermore, treatment with genetically modifiedL. gasseriled to a significant decrease in the percentage of FoxP3+colonic lymphocytes. Taken together, these data clarify the interaction ofL. gasseriwith the host immune system and support further investigation of thein vivoimmunogenicity ofL. gasseriexpressing both flagellin and candidate vaccine antigens.}, number={11}, journal={CLINICAL AND VACCINE IMMUNOLOGY}, author={Stoeker, Laura and Nordone, Shila and Gunderson, Sara and Zhang, Lin and Kajikawa, Akinobu and LaVoy, Alora and Miller, Michael and Klaenhammer, Todd R. and Dean, Gregg A.}, year={2011}, month={Nov}, pages={1834–1844} }