Dietary Bifidobacterium lactis (HN019) enhances resistance to oral Salmonella typhimurium infection in mice.
The ability of a newly identified probiotic lactic acid bacterial strain, Bifidobacterium lactis (HN019), to confer protection against Salmonella typhimurium was investigated in BALB/c mice. Feeding mice with B. lactis conferred a significant degree of protection against single or multiple oral challenge with virulent S. typhimurium, in comparison to control mice that did not receive B. lactis. Protection included a ten-fold increase in survival rate, significantly higher post-challenge food intake and weight gain, and reduced pathogen translocation to visceral tissues (spleen and liver). Furthermore, the degree of pathogen translocation showed a significant inverse correlation with splenic lymphocyte proliferative responses to mitogens, blood and peritoneal cell phagocytic activity and intestinal mucosal anti-S. typhimurium antibody titers in infected mice; all of these immune parameters were enhanced in mice fed B. lactis. Together, these results suggest that dietary B. lactis can provide a significant degree of protection against Salmonella infection by enhancing various parameters of immune function that are relevant to the immunological control of salmonellosis. Thus dietary supplementation with B. lactis provides a unique opportunity for developing immune-enhancing probiotic dairy food products with proven health benefits.
Shu
Q
Q
Milk and Health Research Centre, Massey University, Palmerston North, New Zealand.
Lin
H
H
Rutherfurd
K J
KJ
Fenwick
S G
SG
Prasad
J
J
Gopal
P K
PK
Gill
H S
HS
D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D018988:Bacterial Translocation; D001644:Bifidobacterium; D004032:Diet; D008099:Liver / Q000382:microbiology; D008213:Lymphocyte Activation; D016131:Lymphocyte Subsets / Q000276:immunology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D010587:Phagocytosis; D019936:Probiotics; D012481:Salmonella Infections, Animal / Q000276:immunology / Q000382:microbiology / Q000517:prevention & control*; D012486:Salmonella typhimurium / Q000276:immunology / Q000472:pathogenicity / Q000502:physiology*; D013154:Spleen / Q000382:microbiology; D014774:Virulence
D000907:Antibodies, Bacterial