Analysis of Immune Response and its close cooperation with Intestinal Tract

Our immune system serves to protect us against all kind of threats. A pathogen that successfully crosses the early physical barriers (like skin, epithelial barriers, mucus membranes) is first addressed by our innate immune system. This system that we were born with is a collective of different white blood cells travelling in our tissues. The innate response is a rapid defense system, but is nonspecific and without any memory.

If this first stage fails, dendritic cells will present the antigen to the naïve T helper cells in our adaptive immune system. The adaptive immune system will react specifically, in a more sophisticated way, with a differentiation into effector lymphocytes and memory cells.

The flow of communication between innate and adaptive immunity dictates how we will respond in a Th1/Th2/Th17/T reg model. The role of the regulatory T cells is crucial as they are needed to suppress the entire activation once the germ has been defeated.

It is fascinating to see how the gastrointestinal system, a highly sophisticated multilayered system, contributes to immune tolerance and the avoidance of excessive inflammation, neuroinflammation and autoimmune pathology.

In this lecture, based on literature study, we will show the mutual relation between microbiome and intestinal permeability by the analysis of the different layers of intestinal barrier and the mechanism behind it. Especially the short chain fatty acids, commensal metabolites issued by fermentation of host and exogenous prebiotics, dictate the crosstalk between microbiome and host and modulate immunity on a local level next to the systemic level. By understanding these key regulating factors, we try to approach and rebuild the normal permeability.

Given the importance of the intestinal barrier, we can state that gut health requires multilevel support. It forms the basis of any successful therapy in immune related pathologies.