Immune response in digestive and metabolic disorders Flashcards
Histological appearance of coeliac disease?
Inflammatory cells, tissue, damage, lengthening of crypts
Consequence of coeliac disease?
Malabsorption, diarrhoea
What is coeliac disease?
Inflammation of the upper SI due to response to gluten
How s coeliac disease managed?
Remove gluten from diet
How is coeliac disease caused?
Susceptible individuals express an enzyme that modifies peptides released from gluten so they bind MHC class II Over activation of CD4 = pro inflammatory cytokines
What evidence suggests coeliac disease has genetic and environmental factors?
95% of patients have a specific HLA allele but most people with this allele don’t have coeliac disease
Only an 80% concordance in identical twins
Downs syndrome have 6x increased risk - may have something to with chromosome 21
Cause of inflammatory bowel disease? Example
Antigens derived from commensal microbiota in intestines
Chrons
Name and describe 4 aspects of immune system of the gut
Mucin/mucosa = highly glycosylated - traps bacteria
Ciliated epithelium = waft bacteria into stomach
Peyers patch = sample antigens and activate DCs = activate Th and Treg
B cells secrete IgA
Paneth cells secrete AMPs
Oral manifestations of chrons?
Chelitis and ulceration
What genetic variant causes Chrons and what is the effect?
Variant of NLR2 = can’t recognise commensal bacteria, impaired AMP secretion
Pathogenesis of Chrons?
Failure to regulate immune response against commensal bacteria in the gut
Innate and adaptive (AMPS and CD4) activated = inflammation and destruction
How do metabolic disorders come about?
Acquired
What suggests there is an environmental factor of Chrons disease?
Relationship with other conditions e.g. obesity
What causes gout?
Increased uric acid deposition this activates inflammosomes and increased Il1 secretion = macrophages
Difference between primary and secondary gout?
Primary = increased uric acid production Secondary = decreased uric acid excretion
