IBD and GI Mucosal Immunology

9 flashcards · Other · by Anonymous Sloth

  1. Describe the function of the colonic mucosa

    Part of the GI tract that particularly exerts a physiological immunity It is able detect contents in the lumen Differential between commensal cultures from pathogens requiring a strong immune response

  2. Describe the basis of immune surveillance

    Antigen processing Antigen is any molecule that has the capability of producing an immune response The immune system should differentiate between self-antigens and foreign antigens effectively

  3. What are the challenges in immune surveillance in the GI tract

    Self-tolerance (non-responsive to self-antigens) Exogenous tolerance (non-responsive to benign environmental antigens such as food and microbes) Effective immune response (neutralise or control harmful pathogens or toxins) A very difficult balance

  4. Describe the interaction between the GI tract and the environment

    GI tract is a oral to anal tube that allows nutrients to enter and waste to leave the body It interacts with the physical environment leaving it prone to harm Requires a robust immune system for surveillance

  5. What are the facets to immunity in the colon

    Epithelium (physical barrier with tight junction that's selectively permeable) Mucus layer (traps microbes from host cells) Innate immune system (TLRs, anti-microbial peptides IgA) APC (dendritic cells and macrophage) Tolerance vs adaptive immunity activation Chemokines and cytokines (mediators)

  6. What are the cells of the immune system

  7. Describe the function of cytokines

    Soluble mediators of the immune response Ampllification, cascade induction, antagonism and synergy of the immune response

  8. Function of Peyer's patch

    Aggregations of organised lymphoid cells in the gut. Perform a role in the surveillance of the microbiome of the GI tract commensal bacteria (tolerance) Pathogens (immune response)

  9. Function of macrophages in mucosal immunity

    Innate immune system (First line of defence of the gut) Engulfs and digests foreign antigens Secretes cytokines Antigen presenting to modulate adaptive immune response