It has become increasingly clear that many diseases are triggered or influenced by changes in bacterial populations in the gut. The general view up until now has been that bacteria stimulate the immune system, which leads to inflammation or autoimmune diseases.
In a recent study published in Immunity, researchers have painted a more complex picture. The immune system of the gastrointestinal tract not only prevents the invasion of pathogens, but it is more actively involved in the balance of gut bacteria. They propose that there are faults in immune regulation that lead to changes in the microbial balance which then feed back into the immune system.
Researchers determined that the regulation by immune T cells of immunoglobulin A (IgA) is crucial for the balance of bacterial communities in the gut. They identified that the immune system "sees" and responds differently to different bacterial populations. Healthy, balanced bacterial populations are perceived as "self" and activate a maturation of the immune system and gut responses (regulatory T cells and IgA), while poor and unbalanced bacterial populations are perceived as "non-self" and activate responses targeted at eliminating them (T cells with inflammatory properties and IgG or IgE responses).
This study has an impact on how we understand immune-related disorders associated with bacteria dysbiosis in the gut. In order to establish a healthy microbial balance, we need to interfere with the bacteria by providing probiotics, as well as with the immune system by correcting other environmental triggers and deficiencies. It is important to assess and support optimal vitamin D levels due to its role with T regulatory cells.
In addition, saccharomyces boulardii is nonpathogenic, probiotic yeast with multiple mechanisms of action. It has profound effects on protecting the intestinal epithelial cells and maintaining intestinal barrier function. In addition, it powerfully increases sIgA secretion. This is huge for boosting the immune system since sIgA is the body’s primary immune response.
It is amazing how the immune system identifies and reacts to different microbial populations. This provides us with a stronger knowledge of the harmonious relationships between the immune system and gut bacteria. As a result, we can therapeutically support the gut, reestablish a proper microbial balance and restore health.
For a closer look at GI health, please listen to our Clinical Rounds call from June 19, 2013, Treating Functional Gut Disorders Naturally, with Susanne Bennett, DC, CCSP.
Source: Shimpei Kawamoto, Mikako Maruya, Lucia M. Kato, Wataru Suda, Koji Atarashi, Yasuko Doi, Yumi Tsutsui, Hongyan Qin, Kenya Honda, Takaharu Okada, Masahira Hattori, Sidonia Fagarasan. Foxp3 T Cells Regulate Immunoglobulin A Selection and Facilitate Diversification of Bacterial Species Responsible for Immune Homeostasis. Immunity, 2014; DOI: 10.1016/j.immuni.2014.05.016