title: Germination-independent induction of cellular immune response by Bacillus subtilis spores displaying the C fragment of the tetanus toxin.
abstract: Bacillus subtilis spores displaying the tetanus toxin fragment C (TTFC) on their surface have been previously shown to induce the production of specific IgG and secretory IgA in mice immunized through the oral or nasal route. Aim of this study was to analyze whether these spores were also able to induce cellular immunity, and whether such immune response was dependent on spore germination in the animal gastro-intestinal tract (GIT). We first developed a germination defective strain of B. subtilis unable to produce viable cells inside the mouse GIT. Germination-defective and congenic wild-type spores both expressing TTFC on their surface were then used to orally immunize Balb/C mice. Both types of spores induced spleen and mesenteric lymph nodes cell proliferation as well as production of IFNgamma but not of IL-4 and IL-10 in both districts. Our results indicate that recombinant spores preferentially induce a strong cell-mediated immune response with a Th1 phenotype, independently from their ability to germinate in the GIT.
authors.affiliation: Department of Structural and Functional Biology, Federico II University of Napoli, via Cinthia, Complesso MSA, 80126 Napoli, Italy.
authors.forename: Emilia M F
authors.initials: EM
authors.lastname: Mauriello
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Cangiano
authors.forename: Francesco
authors.initials: F
authors.lastname: Maurano
authors.forename: Virgilio
authors.initials: V
authors.lastname: Saggese
authors.forename: Maurilio
authors.initials: M
authors.lastname: De Felice
authors.forename: Mauro
authors.initials: M
authors.lastname: Rossi
authors.forename: Ezio
authors.initials: E
authors.lastname: Ricca
mesh_terms: D000818:Animals; D001412:Bacillus subtilis / Q000276:immunology*; D001428:Bacterial Vaccines / Q000276:immunology*; D005260:Female; D007371:Interferon-gamma / Q000096:biosynthesis; D016753:Interleukin-10 / Q000096:biosynthesis; D015847:Interleukin-4 / Q000096:biosynthesis; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D010446:Peptide Fragments / Q000276:immunology*; D013171:Spores, Bacterial / Q000276:immunology; D013744:Tetanus Toxin / Q000276:immunology*
chemical_list: D001428:Bacterial Vaccines; D010446:Peptide Fragments; D013744:Tetanus Toxin; C040635:tetanus toxin fragment C; D016753:Interleukin-10; D015847:Interleukin-4; D007371:Interferon-gamma