Immunology and The Gut

Your Gut and the Immune System

The gastrointestinal system plays a central role in the immune system. Outside of our skin, it is the main route of contact with the outside world and is overloaded every day with external stimuli. Most of these interactions are with essential nutrients, fluids, and symbiotic microbes like probiotics that the body needs to survive but often the gut is the introductory route for dangerous pathogens (microbes that cause disease) and toxic substances. The importance of the role of the gut in our immune systems is evidenced by the enormous presence of immunological tissue that resides within it. It is this tissue that must scan everything that is introduced into the body via the mouth and decide if it is vital for survival (food, water, minerals) or a potentially deadly threat (toxins, pathogenic microbes).

MALT and GALT

Mucosal-associated lymphoid tissue (MALT), which is responsible for initiating immune responses in the gut, represents almost 70% of the entire immune system. Gut-associated lymphoid tissue (GALT) is the prominent component of MALT and about 80% of our body's plasma cells (antibody-producing cells) reside in GALT. When your gut is healthy, these powerhouses of the immune system spring into action when pathogenic organisms like parasites or ulcer-causing bacteria like H. pylori are detected. However, if the gut is in dysbiosis, meaning an unhealthy imbalance of healthy flora to pathogens, as in cases of inflammatory bowel disease states, eg., Ulcerative colitis, Crohn's, then we see the immune cells in GALT reacting to healthy food instead of pathogenic organisms.¹

>Aside from constantly working to prevent infections in our gut and making sure we don't overreact to healthy nutrients, GALT is also affected positively by probiotic microbes that live in our gut. In fact, certain studies have provided evidence that suggests that proper GALT development early in life is dependent on its interaction with probiotic species B. fragilis and B. subtilis2. It also seems that other probiotic strains such as Lactobacillus GG, Bifidobacterium lactis and Saccharomyces boulardii enhance the production of IgA, a powerful antibody that binds to pathogens in the gut, marking them for death by other immune cells. If you're worried more about calming down inflammation or reducing an overactive autoimmune condition, then the Bifidobacteria and Lactobacillus species have got you covered. They induce expression of anti-inflammatory cytokines, TGFβ and IL-102. These cytokines tell key immune cells called T-regulatory cells, to calm the immune system down.

How Probiotics Affect the Immune System

Since it is still cold and flu season, you're probably more worried about upper respiratory infections (URI's) than catching a tummy bug on an exotic summer trip. Luckily, probiotics really do play an enormous role in helping to prevent URI's. In 2003, Glück and Gebbers published a paper describing a clinical trial to test the efficacy of the ingestion of 5 probiotic strains in preventing the occurrence of the potentially pathogenic bacteria (PPB) in their nasal passages. It was found that there was a significant reduction of the PPB in the group who consumed the probiotics regularly, suggesting a protective element provided by these probiotic strains against the potential development of upper respiratory infections. In another study conducted on college students in 2011, it was found that a daily dose of just 2 strains (Lactobacillus rhamnosus and Bifidobacterium animalis ssp. lactis) for 12 weeks was sufficient to significantly reduce the duration and severity of URI among the participants.

So how does Sun Genomics fit into this? With Floré we can include these strains and/or other supportive strains in your formulation at the concentration you need as indicated in your microbiome data. You can also diversify your probiotic profile by increasing your intake of probiotic foods like yogurt, kefir, kombucha, sauerkraut, and kimchi.

Take care of your gut and it will take care of you.