Immunome Research
Open Access

Microbiome-Immune Axis and Infections of Immune System

Kohei Shitara^{* *}Correspondence: Kohei Shitara, Department of Immunology, University of York, New York, UK, Email:

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About the Study

The human immune system is a complex network of cells, tissues, and molecules that defend the body against pathogens and maintain health. Emerging research has revealed a crucial relationship between the microbiome and the immune system, known as the microbiome-immune axis. This bidirectional interaction has significant implications for human health, as it influences immune modulation, responses to infections, and the development of various diseases.

Microbiome-immune axis

Microbiome composition: The human microbiome consists of trillions of microorganisms, including bacteria, viruses, fungi, and archaea, inhabiting various body sites, such as the gut, skin, oral cavity, and respiratory tract.

Microbiome diversity: A diverse microbiome is essential for maintaining a balanced and healthy immune system. The composition and diversity of these microbial communities vary between individuals and can be influenced by factors such as diet, genetics, and environmental exposures.

Immune system's role

Innate and adaptive immunity: The immune system comprises two main components: innate and adaptive immunity. Innate immunity provides immediate, non-specific defense mechanisms, while adaptive immunity is highly specific and develops memory responses to pathogens.

Immune Tolerance: The tolerance mechanisms prevent the immune system from attacking self-tissues and maintaining a state of equilibrium between defense against pathogens and tolerance to the body's own cells.

Immune modulation by the microbiome

Gut-Associated Lymphoid Tissue (GALT): The gut is home to a significant portion of the body's immune cells and is heavily influenced by the gut microbiota. GALT plays a crucial role in immune modulation by maintaining tolerance to harmless commensal bacteria while responding to harmful pathogens.

Microbial metabolites: Gut microbes produce various metabolites, such as Short-Chain Fatty Acids (SCFAs) and immunomodulatory molecules, which interact with immune cells and influence their function.

Microbiome-immune axis in early life

Neonatal immune development: The initial colonization of an infant's gut by microbes plays a pivotal role in shaping the immune system. Early exposure to beneficial microbes can enhance immune maturation and protect against allergic and autoimmune diseases.

Cesarean section vs. vaginal birth: The mode of delivery significantly impacts the infant's microbiome and immune development. Babies born via cesarean section may have altered microbiota colonization and potentially higher susceptibility to certain health conditions.

Impact on health and disease

Inflammatory Bowel Disease (IBD): Dysbiosis of the gut microbiota has been implicated in the development and exacerbation of IBD, including crohn's disease and ulcerative colitis.

Allergies and autoimmune diseases: Alterations in the gut microbiome composition have been linked to an increased risk of allergies and autoimmune diseases, highlighting the microbiome's role in immune dysregulation.

Microbiome-immune axis and infections

Defense against pathogens: A balanced gut microbiome contributes to the body's defense against pathogenic invaders by occupying ecological niches and producing antimicrobial compounds.

Gut dysbiosis and infections: Dysbiosis, characterized by an imbalance in the gut microbiota, can compromise immune responses and increase susceptibility to infections.

Therapeutic applications

Probiotics: These supplements containing beneficial bacteria can be used to restore microbial balance in the gut and modulate immune responses. They have shown promise in alleviating conditions such as diarrhea and irritable bowel syndrome.

Prebiotics: These are dietary components that promote the growth of beneficial gut bacteria. They can be utilized to support a healthy microbiome and, subsequently, immune function.

FMT for recurrent infections: Fecal Microbiota Transplantation (FMT) involves transferring fecal material from a healthy donor to a recipient to restore a balanced microbiome. It has shown the remarkable success in treating recurrent Clostridium difficile infections and is being explored for other conditions.

FMT in immunotherapy: Research is ongoing to explore the potential of FMT in enhancing the effectiveness of cancer immunotherapies by modulating the immune response in the gut.

The microbiome-immune axis represents a dynamic and intricate relationship between the human microbiome and the immune system.

Understanding this axis is crucial for deciphering the mechanisms of immune modulation, the development of various diseases, and the potential for innovative therapeutic interventions.