title: Early treatment with Lactobacillus delbrueckii strain induces an increase in intestinal T-cells and granulocytes and modulates immune-related genes of larval Dicentrarchus labrax (L.).
abstract: Lactobacillus delbrueckii ssp. delbrueckii (AS13B), isolated from the gut of adult Dicentrarchus labrax, was administered live to developing sea bass using rotifers and Artemia as live carriers. Immune-related gene transcripts were quantified in post-larvae at day 70 post-hatch (ph) and histology, electron microscopy and immunocytochemistry of the intestinal tissue were performed at day 74 ph. Since the probiotic was orally administered the studies were focused on intestinal immunity. In treated fish gut integrity was unaffected, while the density of T-cells and acidophilic granulocytes in the intestinal mucosa was significantly higher than in controls. Probiotic-induced increases in intestinal T-cells and total body TcR-beta transcripts are first reported in fish. Significantly lower IL-1beta transcripts and a trend towards lower IL-10, Cox-2 and TGF-beta transcription were found in the treated group. Evidence is provided that early feeding with probiotic-supplemented diet stimulated the larval gut immune system and lowered transcription of key pro-inflammatory genes.
authors.affiliation: Department of Environmental Sciences, Tuscia University, Viterbo, Italy.
authors.forename: Simona
authors.initials: S
authors.lastname: Picchietti
authors.forename: Anna Maria
authors.initials: AM
authors.lastname: Fausto
authors.forename: Elisa
authors.initials: E
authors.lastname: Randelli
authors.forename: Oliana
authors.initials: O
authors.lastname: Carnevali
authors.forename: Anna Rita
authors.initials: AR
authors.lastname: Taddei
authors.forename: Francesco
authors.initials: F
authors.lastname: Buonocore
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Scapigliati
authors.forename: Luigi
authors.initials: L
authors.lastname: Abelli
mesh_terms: D000818:Animals; D001492:Bass / Q000235:genetics / Q000276:immunology / Q000382:microbiology*; D001835:Body Weight / Q000502:physiology; D049109:Cell Proliferation; D029941:Fish Proteins / Q000235:genetics*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006098:Granulocytes / Q000166:cytology*; D006854:Hydrocortisone / Q000097:blood; D007150:Immunohistochemistry; D007422:Intestines / Q000166:cytology*; D048668:Lactobacillus delbrueckii / Q000502:physiology*; D007814:Larva / Q000235:genetics / Q000276:immunology / Q000382:microbiology; D046529:Microscopy, Electron, Transmission; D019936:Probiotics; D013601:T-Lymphocytes / Q000166:cytology*
chemical_list: D029941:Fish Proteins; D006854:Hydrocortisone