mucosal immunity Flashcards
What is the underlying mechanism of signal 1 communicating Ag specificity
MHC-Ag interacts with T cell receptor and signal 1 tells T cell it recognises the Ag presented by the DC (dendritic cell)
What is the underlying mechanism of signal 2 of co-stimulation in danger
Danger signals (PAMPs - pathogen associated molecular patterns) up-regulate B7 on APC (antigen presenting cell)
B7 signals to the T cell via CD28
What signal should food result in
Signal 1 not 2 so that the DC (dendritic cell) will tell the T cell that the Ag is not dangerous and T cell should not respond
What is the mechanism of anergy in regulatory and inhibitory memory
T cells lives but become unresponsive memory cell
What is the mechanism of inhibitory cytokines (e.g IL-10) in regulatory and inhibitory memory
Inhibits or turns off T cells and innate cells
What is the mechanism of regulatory T cells in regulatory and inhibitory memory
Control immune responses like Th cells (via MHC class II)
Inhibit functions
Can make IL-10
What is the antibody with the predominant antibody response in the intestine
IgA - well suited for mucosal immunity
What is a characteristic of IgA’s dimeric structure
IgA’s dimeric structure is good at clumping together and neutralising pathogens
What is the role of tight junctions in mucosal immunity
Prevent epithelium penetration
What is the role of the mucus layer in mucosal immunity
Prevents microbes getting to epithelium
What is the role of anti-microbial peptides in mucosal immunity
Damage microbes that get too close to epithelium
What is the role of IgA in mucosal immunity
Specialised for neutralising and blocking microbes
What is the hygiene hypothesis
Reduced exposure to pathogens correlates with an increase in autoimmune and allergic diseases
What is the use of immune regulatory mechanisms and give examples
Used to limit immune inflammation and prevent immune pathology e.g Il-10 and Tregs
