Food allergy Flashcards
what is the name if you are not allergic to something, just don’t like it
psychosomatic effect
what causes a food allergy
when your immune system attacks a food protein
what links the symptoms to the allergy
no correlation
what is the gut challenged by
constant bombardment of foreign antigens
what happens when the mucosal mast cells are activated
triggers release of inflammatory mediators
- transepithelial fluid loss
- smooth muscle contraction
- vomiting and diarrhoea
- anaphylaxis
when do we know from adverse reactions to food if there is a problem
when the immune system is involved = food allergy
if non-immune mediated = food hypersensitivity
what is the first point of contact with food
gut
food consumed travels to mucosa
what is the mucosa
inner most layer of the gut
what defence is there against microbes in the gut
most microbes destroyed by acid in gut
where in the body is there the largest population of immune cells
gut
where do the lymphatics from the peyers patch and villi go
drain into the mesenteric lymph node
what is the lamina propria
close network of loose connected tissues in the villi
what replenish the villi - damaged epithelial cells
crypts - host stem cells
how does the intestine prevent invasion
epithelium with thick overlying mucus form barrier against microbial invasion
what cells are make up the peyers patch
mix of immune cells
what does the peyers patch have that aids its function
thinner mucus layer and phagocytic cells
what is the peyer patches - M cell function and process
sampling antigens in lumen then transport to antigen-presenting cell on the basolateral side via transcytosis
what do dendritic cells do
extend dendrites between epithelial cells to sample antigens that are then broken and presented to lymphocytes
usually causes an anti-inflammatory response
when might inflammatory bowel disease be caused
dendritic cells with antigen travel to T cells in peyers patch
if T cells non-functional can cause inflammatory bowel disease
how is inflammation stopped
T cells migrate to villi
secretion suppresses immune cells
stop inflammation
how are inflammatory molecules released
epithelium contact with bacteria
activates immune cells
release inflammatory molecules
what are neturophils and their function
types of WBC
needed for clearance of bacteria
how do neutrophils prevent the inflammatory condition getting worse
undergo self cell death - leave neutrophil extracellular trap
what happens to fight against parasites
attracted to parasite
release large amount WBC to destroy it
antibodies recognise some characteristics of cells and bind, label cells for destruction
cells e.g. mast, recognise the antibodies
release mediators
destroy invader
