Mucosal immunity tutorial Flashcards
What kind of response do epithelial tissue form?
Protect with less inflammation. (tolerogenic) Tissue resident cytokines are present which reduce inflammation and prevent tissues from inflaming.
What do commensal organisms help with?
Important for the synthesis of important metabolites.
Important for breakdown of plant fibers into fatty acids.
Inactivate toxic substances
Prevent pathogens from benefiting from the nutrients of the gut.
Interact with gut lymphoid tissue to assist in development of gut associated lymphoid tissue
What do peyer’s patches do?
Peyer’s patches are secondary lymphoid organs that underlie gut epithelium
What are M cells?
Antigen enters a Peyer’s patch from gut via M cells.
What are goblet cells?
Cells that produce mucous
What is the purpose of follicles of the intestine?
They consist of many B cells where isotype switching and affinity maturation takes place.
What cytokines are important for tolerogenic response?
TGF-beta and IL-10 tell a DC that it needs to make Treg helper cells rather than Th1, 2 or 17.
What other process besides M cells are involved in the immune response to antigens in the gut?
DCs can extend finger like projections into the luminal surface of the gut and phagocytose antigens from there.
How and where are naive B cells activated in the mucosa?
Naïve B cells are activated in Peyer’s patches and mesenteric lymph nodes by antigen and TFH cells to give rise to plasma cells
What triggers isotype switching in mucosal cells to produce IgA and IgM antibodies?
Some plasma cells undergo isotype switching triggered by TGFβ, and iNOS, APRIL and BAFF produced by DCs in combination with IL-4
How do IgA deficient people respond to compensate for deficiency?
They produce more IgM and IgG, IgM can go externally to respond to external infections.
Why do children who have had their tonsils or adenoids remove respond less effectively to the oral polio vaccine than children who still have these tissues?
Early exposure is important for the development of an immune response to polio.
Tonsils and adenoid are located in the oral cavity and are composed of extensive secondary lymphoid tissue making up Waldeyer’s ring.They are responsible for the production of secretory IgA specific for infectious material entering the gut airways. The oral polio vaccine elicits the most effect protective immunity through the production of secretory IgA including the secondary lymphoid tissues of Waldeyer’s ring.
