Open AccessPredominance of a bacteriocin‐producing Lactobacillus salivarius component of a five‐strain probiotic in the porcine ileum and effects on host immune phenotype
Author(s) -
Walsh Maria C.,
Gardiner Gillian E.,
Hart Orla M.,
Lawlor Peadar G.,
Daly Mairead,
Lynch Brendan,
Richert Brian T.,
Radcliffe Scott,
Giblin Linda,
Hill Colin,
Fitzgerald Gerald F.,
Stanton Catherine,
Ross Paul
Publication year - 2008
Publication title -
fems microbiology ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.377
H-Index - 155
eISSN - 1574-6941
pISSN - 0168-6496
DOI - 10.1111/j.1574-6941.2008.00454.x
Subject(s) - biology , bacteriocin , lactobacillus salivarius , probiotic , microbiology and biotechnology , strain (injury) , immune system , ileum , phenotype , host (biology) , lactobacillus , lactobacillaceae , bacteria , immunology , genetics , gene , anatomy , biochemistry , antimicrobial
Relative predominance of each of five probiotic strains was investigated in the ileum of weaned pigs, compared with that in feces, when administered in combination at c . 5 × 10 9 CFU day −1 for 28 days. Probiotic was excreted at 10 6 –10 9 CFU g −1 feces, while ileal survival ranged from 10 2 to 10 6 CFU g −1 digesta. In contrast to the feces, where Lactobacillus murinus DPC6002 predominated, the bacteriocin‐producing Lactobacillus salivarus DPC6005 dominated over coadministered strains both in the ileum digesta and in mucosa. Probiotic administration did not alter counts of culturable fecal Lactobacillus or Enterobacteriaceae but higher ileal Enterobacteriaceae were observed in the ileal digesta of probiotic‐fed pigs ( P <0.05). We observed decreased CD25 induction on T cells and monocytes ( P <0.01) and decreased CTLA‐4 induction ( P <0.05) by the mitogen phytohemagglutinin on CD4 T cells from the probiotic group. Probiotic treatment also increased the proportion of CD4+ CD8+ T cells within the peripheral T‐cell population and increased ileal IL‐8 mRNA expression ( P <0.05). In conclusion, superior ileal survival of L. salivarius compared with the other coadministered probiotics may be due to a competitive advantage conferred by its bacteriocin. The findings also suggest that the five‐strain combination may function as a probiotic, at least in part, via immunomodulation.