Modulation of Nonspecific Mechanisms of Defense by Lactic Acid Bacteria: Effective Dose

• Published in: Journal of dairy science 1999-05, Vol.82 (5), p.863-869
• Main Authors: Donnet-Hughes, A., Rochat, F., Serrant, P., Aeschlimann, J.M., Schiffrin, E.J.
• Format: Article
• Language: English
• Subjects: Adult; Air. Soil. Water. Waste. Feeding; Animals; Biological and medical sciences; Biotechnology; Colony Count, Microbial; dose response; Environment. Living conditions; Escherichia coli - immunology; Feces - microbiology; Female; Fermentation; Food industries; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Humans; Immunobiology; lactic acid bacteria; Lactobacillus acidophilus - isolation & purification; Leukocytes - immunology; Male; Medical sciences; Middle Aged; Milk - microbiology; Milk and cheese industries. Ice creams; Modulation of the immune response (stimulation, suppression); Phagocytosis; Probiotics; Public health. Hygiene; Public health. Hygiene-occupational medicine; Respiratory Burst
• ISSN: 0022-0302; 1525-3198
• DOI: 10.3168/jds.S0022-0302(99)75304-X

The purpose of this study was to determine the effect of a fermented milk product containing Lactobacillus johnsonii La1 (formerly known as Lactobacillus acidophilus La1) on the phagocytic activity of peripheral blood leukocytes in healthy adult volunteers. Furthermore, we sought to define the effective doses of the bacteria, examine the effect on respiratory burst activity, and, finally, examine the contribution made by the starter culture to the biological effects. Volunteers were randomly distributed among three groups; each subject received one pot (150ml) of fermented milk each day for 3 wk. The first two groups received a freshly prepared product fermented by Streptococcus thermophilus (group A) alone or S. thermophilus and 107 cfu/ml L. johnsonii La1 (group B). Group C received a product stored for a period of 21 to 28 d and that contained S. thermophilus and 106cfu/ml of L. johnsonii La1. Ingestion of L. johnsonii La1 did not significantly increase fecal lactobacilli counts. However, L. johnsonii La1 was able to survive intestinal transit and was only recovered from the feces of the volunteers of groups B and C. The fermented base alone showed a weak effect on respiratory burst but not on phagocytic activity. However, the product containing 107cfu/ml L. johnsonii La1 significantly enhanced both functions. The product containing 106cfu/ml of L. johnsonii La1 had no significant effect on either function. These results suggest that fecal persistence may not necessarily reflect in vivo colonization and may not be a prerequisite for all forms of immune reactivity.