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Mechanisms of action of probiotics

W Allan Walker1

  • 1Division of Nutrition and Department of Pediatrics, Harvard Medical School, Boston, USA. wwalker@partners.org

Clinical Infectious Diseases : an Official Publication of the Infectious Diseases Society of America
|January 10, 2008
PubMed

Insights

Bacterial colonization is crucial for developing a healthy gut immune system in newborns. Proper colonization prevents immune imbalances and diseases like necrotizing enterocolitis, paving the way for probiotic therapies.

Area of Science:

  • Immunology
  • Microbiology
  • Gastroenterology

Background:

  • Newborns transition from a sterile womb to a bacteria-rich environment, necessitating robust immune defenses.
  • Intestinal immune system development is dependent on exposure to bacteria for proper maturation and function.

Purpose of the Study:

  • To review the critical role of bacterial colonization in establishing normal mucosal immune function.
  • To discuss the clinical implications of insufficient bacterial colonization for disease development.

Main Methods:

  • Literature review focusing on the interplay between gut bacteria and the host immune system.
  • Analysis of immune cell balance (T-helper 1/T-helper 2 cells) and its relation to disease.

Main Results:

  • Bacterial colonization is essential for the development of adaptive mucosal immunity.
  • An imbalance in T-helper cells, with elevated T-helper 2 responses, is linked to autoimmune diseases and gut inflammation, including necrotizing enterocolitis.

Conclusions:

  • Understanding bacterial-epithelial interactions is key to developing strategies for immune modulation.
  • Probiotics show promise in preventing gastrointestinal diseases by influencing gut immune responses.

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