Bifidobacteria immune response

The mechanisms by which probiotics (and prebiotics) produce beneficial effects on the gut have not yet been fully elucidated. However, at least three mechanisms of action have been proposed (i) antibacterial agents produced by probiotic organisms may have an inhibitory effect on pathogenic microbes (ii) immune responses may be enhanced to suppress potential pathogens and (iii) competition in the gut epithelium may allow lactic acid bacteria and bifidobacteria to supplant pathogenic organisms. 

The ability of dietary consumption of foods containing LAB to modulate immune responses has been thoroughly studied in animal models. Dietary consumption of LAB and Bifidobacteria strains have been shown to enhance protection against intracellular bacterial pathogens. Physiological responses have been shown to correspond with the cell-mediated immune responses that have the Thl cell bias. 

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