Prebiotics and Immune Function

Role of intestinal flora in health and disease.

Guamer F; Nutr Hosp. 2007; 22 Suppl 2: P-14

• The terms intestinal “microflora” or “microbiota refer to the microbial ecosystem colonizing the gastrointestinal tract.
• The main functions of intestinal microflora include (1) metabolic activities translating into energy and nutrients uptake, and (2) host protection against invasion by foreign microorganisms.
• Intestinal bacteria play an essential role in the development and homeostasis of the immune system.
• Lymphoid follicles within the intestinal mucosa are the main areas for immune system induction and regulation.

Inulin and oligofructose: review of experimental data on immune modulation.

Seifert S, Watzl B. Institute of Nutritional Physiology, Federal Research Centre for Nutrition and Food, 76131 Karlsruhe, Germany.

• First results from human intervention studies suggest that the intake of inulin (IN) and oligofructose (OF) has beneficial effects on the gut-associated lymphoid tissue.
• Data from studies with infants suggest that supplementation with a prebiotic mixture positively affects postnatal immune development and increases fecal secretory IgA.
• The intestinal immune system and especially the immune cells associated with the Peyer’s patches are responsive to a dietary supplement of IN/OF and/or their metabolites.
• The mechanisms of IN/OF include indirect effects such as a shift in the composition of the intestinal flora and the enhanced production of immunoregulatory SCFA and perhaps other bacterial metabolites.
• In conclusion, prebiotic IN/OF clearly modulate immunological processes.

Influence of prebiotics on the human immune system (GALT).

Bodera P. Natur Produkt Zdrovit Ltd., Warszawa, Poland.

• The knowledge about the influence of prebiotics on the gut-associated lymphoid tissues (GALT) for the improvement of human health is still growing.
• This paper reviews the latest evidence for the immunity-enhancing effects of prebiotics.
• There is convincing preliminary data to suggest that the consumption of prebiotics can modulate immune parameters in GALT, secondary lymphoid tissues and peripheral circulation.
• There is increasing evidence that the newly described prebiotics and innovative means of administration can modulate various properties of the immune system, including those of the gut-associated lymphoid tissues (GALT).

Inulin and Oligofructose: Review of Experimental Data on Immune Modulation.

Stephanie Seifert and Bernhard Watzl; J Nutr. 2007; 137: 2563S

• First results from human intervention studies suggest that the intake of inulin (IN) and oligofructose (OF) has beneficial effects on the gut-associated lymphoid tissue.
• Animal studies confirm the observations from human trials and give more insight into the immune tissue- specific effects of IN/OF.
• A clear outcome of the animal studies is that the intestinal immune system and especially the immune cells associated with the Peyer’s patches are responsive to a dietary supplement of IN/OF and/or their metabolites.
• The mechanisms of IN/OF include indirect effects such as a shift in the composition of the intestinal flora and the enhanced production of immunoregulatory SCFA and perhaps other bacterial metabolites.
• In conclusion, prebiotic IN/OF clearly modulate immunological processes at the level of the gut-associated lymphoid tissue, which may be associated with significant health benefits in infants and patients with intestinal inflammatory diseases.

Prebiotics, immune function, infection and inflammation: a review of the evidence.

Lomax AR, Calder PC. Institute of Human Nutrition, School of Medicine, University of Southampton, Tremona Road, Southampton, UK. arl203@soton.ac.uk

• In man, two studies in children and nine studies in adults indicate that the adaptive immune system may be modified by beta2-1 fructans.
• Thirteen studies in animal models of intestinal infections conclude a beneficial effect of beta2-1 fructans.
• Human studies report some benefits regarding inflammatory bowel disease (four positive studies) and atopic dermatitis (one positive study),
• Overall the results indicate that beta2-1 fructans are able to modulate some aspects of immune function, to improve the host’s ability to respond successfully to certain intestinal infections, and to modify some inflammatory conditions.