The Role of the Microbiota in Intestinal Health
The microbiota, a varied microbial community found in the human intestine, has a role in an individual's physiology in both health and sickness. By activating defense mechanisms, creating chemicals that block immune responses, and competing for metabolites, this microbiota promotes colonization resistance to the invasive pathogens.
Identification of Commensal Bacteria
The precise commensal bacteria that support immune-mediated defense and host resistance are yet mostly unidentified (Sophie Thiemann, Nathiana, Richard and Till 683).
Influence of Microbiota Composition on Disease Severity
What level of protection results from less Salmonella tissue invasion? How do resident bacteria improve IFN production to provide protection? In the research, isogenic mouse lines with different microbiota profiles were used to demonstrate how the severity of a disease caused by enteric Salmonella Typhimurium infection can be strongly modulated using microbiota composition in single lines. Age and gender-matched mice were obtained from various specific pathogen-free breeding facilities and placed in the vivarium for two weeks to permit adjustment to environmental conditions such as diet. Then the mice were pretreated with a dose of streptomycin and later they were orally infected 24 hours later with Salmonella Typhimurium (Sophie Thiemann, Nathiana, Richard and Till 685).
Impact of Microbiota on Intestinal Inflammation and Susceptibility to Infection
The results indicated that shifting a restricted community of cultivable intestinal commensals from protected into susceptible mice reduces Salmonella Typhimurium tissue colonization and disease severity. This result firmly established that the intestinal microbial affects the severity of intestinal inflammation and the susceptibility to enteric infection. Furthermore, treatment with different antibiotics resulted in distinct changes in the microbiome that were related to varying susceptibility to Salmonella-induced colitis (Sophie Thiemann, Nathiana, Richard and Till 687).
Mechanism of Microbiota-Induced Protection
This outcome meant that prolonged survival, ameliorated weight loss, and the reduced tissue colonization relies on microbiota-enhanced IFNβ production since IFNβ deficient mice do not show protective effects. After the commensal community, the CD4+ T cells and innate cells increase in number exhibiting high levels of IFNβ. Therefore, different microbiota members prevent the intestinal Salmonella infection by promoting antibacterial IFNβ responses. Conclusively, the research revealed a mechanism in which intestinal bacteria lead to amelioration of Salmonella infection through microbiota-induced priming of a protective antibacterial response in the mucosal immune system (Sophie Thiemann, Nathiana, Richard and Till 690).
Works Cited
Sophie Thiemann, Nathiana, Richard and Till. “Cell Host & Microbe: Enhancement of IFNϒ Production by Distinct Commensalism Ameliorate Salmonella-induced Disease.” Biology Article, (June, 2017): 682-692
