ABSTRACT
The human intestinal isolate Lactobacillus johnsonii NCC 533 (La1) is a probiotic strain with well-documented antimicrobial properties. Previous research has identified the production of lactic acid and bacteriocins as important factors, but that other unidentified factors are also involved. We used the recently published genome sequence of L. johnsonii NCC 533 to search for novel antipathogen factors and identified three potential gene products that may catalyze the synthesis of the known antimicrobial factor hydrogen peroxide, H(2)O(2). In this work, we confirmed the ability of NCC 533 as well as eight different L. johnsonii strains and Lactobacillus gasseri to produce H(2)O(2) when resting cells were incubated in the presence of oxygen, and that culture supernatant containing NCC 533-produced H(2)O(2) was effective in killing the model pathogen Salmonella enterica serovar Typhimurium SL1344 in vitro.
Subject(s)
Antibiosis , Hydrogen Peroxide/metabolism , Lactobacillus/metabolism , Salmonella typhimurium/drug effects , Salmonella typhimurium/growth & development , Animals , Cats , Dogs , Humans , Lactobacillus/genetics , Lactobacillus/isolation & purification , Stem CellsABSTRACT
T evaluate the effect of supplementation with Enterococcus faecium strain SF68 (NCIMB10415) on immune function, responses to a multivalent vaccine were investigated in kittens given palatability enhancer with or without E. faecium SF68 daily. E. faecium SF68 was detected in the feces of seven of nine treated cats. Supplementation of kittens with E. faecium SF68 did not affect developmental parameters. The percentage of CD4+ lymphocytes was significantly higher in the treatment group. There were no statistical differences in measurements of any other nonspecific or specific immune parameters between groups.
Subject(s)
Cats/immunology , Enterococcus faecium , Intestines/drug effects , Probiotics/pharmacology , Animals , Animals, Newborn , Blood Cell Count/veterinary , Dietary Supplements , Feces/microbiology , Immunoglobulins/blood , Intestines/microbiology , Probiotics/administration & dosage , Specific Pathogen-Free OrganismsABSTRACT
The gut microflora play a crucial role in several physiologic functions of the host, including maturation of the gut-associated lymphoid tissues during the first months of life. Oral administration of probiotic lactic acid bacteria (LAB) modulates the immune system of humans and some laboratory animals. This effect has never been examined in dogs; therefore, our aim was to study the capacity of a probiotic LAB to stimulate immune functions in young dogs. Puppies were allotted to two groups receiving either a control diet or a diet supplemented with 5 x 10(8) colony forming units (cfu)/d of probiotic Enterococcus faecium (SF68) from weaning to 1 y of age. Fecal and blood samples were collected from the dogs at different time points for the measurement of fecal immunoglobulin (Ig)A, circulating IgG and IgA, and the proportions of lymphoid cell subsets. Fecal IgA and canine distemper virus (CDV) vaccine-specific circulating IgG and IgA were higher in the group receiving the probiotic than in controls. There were no differences in the percentages of CD4(+) and CD8(+) T cells between the groups, but the proportion of mature B cells [CD21(+)/major histocompatibility complex (MHC) class II(+)] was greater in those fed the probiotic. These data show for the first time that a dietary probiotic LAB enhance specific immune functions in young dogs, thus offering new opportunities for the utilization of probiotics in canine nutrition.
