title: Effect of intestinal colonisation by two Lactobacillus strains on the immune response of gnotobiotic mice.
abstract: The effect of intestinal colonisation on the immune system was investigated in germ-free mice monoassociated with Lactobacillus strains isolated from calf faeces. Single doses of Lactobacillus acidophilus L36 or Lactobacillus salivarius L38 were administered to germ-free mice by intragastric gavage. Ten days later, the mice were euthanised. Gene expression levels of interleukin 5 (IL-5), IL-6, IL-10, IL-12b, IL-17a, gamma interferon (IFN-γ), transforming growth factor beta 1 (TGF-β1), and tumour necrosis factor alpha (TNF-α) were quantified in segments of the small and large intestines by real time quantitative polymerase chain reaction. All the mice were colonised rapidly after Lactobacillus administration with intestinal counts ranging from 6.53 to 8.26 log cfu/g. L. acidophilus L36 administration increased the expression of cytokines involved with the Th2 (IL-5, IL-6 and TGF-β1) and Th17 (IL-17a, TNF-α and IL-6) inflammatory response, whereas L. salivarius L38 appeared to stimulate a pattern of less diversified cytokines in the intestine. Intragastric gavage of L. acidophilus L36 and L. salivarius L38 induced similar levels of colonisation in the digestive tracts of germ-free mice but stimulated different immune responses in the intestinal mucosa. The different immunomodulation patterns might facilitate the potential use of these lactobacilli as probiotics to treat distinct pathological conditions, for example protection against Citrobacter rodentium infection by stimulating IL-17 production.
authors.affiliation: Departamento de Biologia Geral, Universidade Federal de Minas Gerais, Campus Pampulha, Av. Antônio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil.
authors.forename: R S
authors.initials: RS
authors.lastname: Steinberg
authors.affiliation: Departamento de Biologia Geral, Universidade Federal de Minas Gerais, Campus Pampulha, Av. Antônio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil.
authors.forename: M
authors.initials: M
authors.lastname: Lima
authors.affiliation: Departamento de Biologia Geral, Universidade Federal de Minas Gerais, Campus Pampulha, Av. Antônio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil.
authors.forename: N L
authors.initials: NL
authors.lastname: Gomes de Oliveira
authors.affiliation: Departamento de Biologia Geral, Universidade Federal de Minas Gerais, Campus Pampulha, Av. Antônio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil.
authors.forename: A
authors.initials: A
authors.lastname: Miyoshi
authors.affiliation: Departamento de Microbiologia, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil.
authors.forename: J R
authors.initials: JR
authors.lastname: Nicoli
authors.affiliation: Departamento de Microbiologia, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil.
authors.forename: E
authors.initials: E
authors.lastname: Neumann
authors.affiliation: Departamento de Biologia Geral, Universidade Federal de Minas Gerais, Campus Pampulha, Av. Antônio Carlos 6627, 31270-901 Belo Horizonte, MG, Brazil.
authors.forename: A C
authors.initials: AC
authors.lastname: Nunes
mesh_terms: D000818:Animals; D058491:Bacterial Load; D016207:Cytokines / Q000096:biosynthesis* / Q000235:genetics; D041981:Gastrointestinal Tract / Q000276:immunology* / Q000382:microbiology*; D020869:Gene Expression Profiling; D005856:Germ-Free Life; D007778:Lactobacillus / Q000254:growth & development* / Q000276:immunology*; D051379:Mice; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D016207:Cytokines
keywords: Lactobacillus; germ-free mice; gut; immunomodulation; probiotics