Interaction between microbiota and immunity in health and disease

Abstract

The interplay between the commensal microbiota and the mammalian immune system development and function includes multifold interactions in homeostasis and disease. The microbiome plays critical roles in the training and development of major components of the host's innate and adaptive immune system, while the immune system orchestrates the maintenance of key features of host-microbe symbiosis. In a genetically susceptible host, imbalances in microbiota-immunity interactions under defined environmental contexts are believed to contribute to the pathogenesis of a multitude of immune-mediated disorders. Here, we review features of microbiome-immunity crosstalk and their roles in health and disease, while providing examples of molecular mechanisms orchestrating these interactions in the intestine and extra-intestinal organs. We highlight aspects of the current knowledge, challenges and limitations in achieving causal understanding of host immune-microbiome interactions, as well as their impact on immune-mediated diseases, and discuss how these insights may translate towards future development of microbiometargeted therapeutic interventions.

The First Report of Diversity Analyses of Skin Microbiome In Indonesian Leprosy Patient

“…The existence of dysregulation of the immune system such as increased Th1 activity can cause changes in the composition of the microbiota and otherwise. 24 Based on the results of this study, there were differences in the order of the microbiota phylum (Firmicutes and Actinobacteria) and genera (Micrococcus and Propionibacterium) composition in leprosy patients during treatment with and without reversal reaction. This result indicate the possibility of reversal reaction in uence on microbiome composition.…”

Daily, Oral FMT for Long-Term Maintenance Therapy in Ulcerative Colitis: Results of a Single-Center, Prospective, Randomized Pilot Study.

“…In our experience, the subjects who responded more favorably were characterized by lower degrees of mucosal damage at the time of FMT induction, as evidenced by lower endoscopic (UCEIS, 5.7 ± 2.1 vs. 8.3 ± 1.5 vs.) and histologic scores (Geboes, 2.5 ± 1.0 vs. 4.3 ± 0.1), as well as lower fecal calprotectin levels (335 ± 50 vs. 929 ± 1144 mcg/g). Immunomodulating effects of the gut microbiota are well-established [27,28] and, in the setting of gross and microscopic mucosal ulceration, FMT may induce uncontrolled and potentially damaging mucosal in ammation secondary to bacterial translocation and systemic immune activation [29,30]. Targeting of UC patients with mild to moderate disease for FMT may therefore be advantageous.…”

Staphylococcus aureus Host Tropism and Its Implications for Murine Infection Models

“…The mouse microbiome is yet another factor affecting the transferability of mouse models. Within recent years, more and more evidence has been collected, showing that the microbiome is an etiologic agent of certain diseases, such as metabolic disorders or inflammatory bowel disease, is implicated in normal human physiology and also interacts strongly with the immune system [ 62 , 128 , 129 , 130 ]. From an ecological point of view, the latter aspect is not surprising, since it is beneficial for both host and commensal to co-evolve toward mutualism and homeostasis.…”

“…A prerequisite for this is a finely tuned balance between the growth of commensal microorganisms and the prevention of their invasion of the body or overuse of resources, which is known as tolerance. The immune system ensures this under homeostatic conditions and is therefore both shaped and modulated by the microbiome throughout life, as comprehensively reviewed by Zheng et al [ 130 ]. As the microbiomes of mice and humans differ significantly, this also leads to immunological differences between the two species that affect the interaction with potential pathogens such as S. aureus [ 62 , 128 ].…”