The human body, especially the intestinal tracts, is a natural habitat for microorganisms that can be beneficial symbionts or pathobionts. Microbiota can interfere with shaping local and systemic immunity, intestinal barrier integrity, and immune function homeostasis. Growing evidence suggests that the onset and progression of immune-mediated diseases such as chronic inflammation and cancer are related to dysbiosis; hence, various therapeutic strategies such as personalized diet, fecal microbiota transplantation (FMT), and phage therapy have been developed to correct the balance of the strains or their metabolites. The evidence has also confirmed the marked impact of the balanced microbiota on the potency of immune checkpoint blockade therapy in certain cancers, such as melanoma and colorectal cancer. Nevertheless, due to our incomplete picture of the gastrointestinal ecosystem, any modulations with enduring effects on the microbial community may have unexpected consequences. In this review, we summarize the adverse aspects of intestinal microbiota and its influence on the functionality of the immune system and the occurrence of associated diseases. Furthermore, we discuss the complexity of the dialogue between the microbiota and host cells, and the challenges of employing current solutions to mitigate the side effects of dysbiosis on the immune system.Author details: Kindly check and confirm the processed corresponding author and their email id are correct and amend if any.That is correct. First and third authors are Co-correspondent.
Khatami et al. (Sat,) studied this question.