Shnyra - GI Immuno Flashcards
Cause of IBD?
Abnormality in the epithelial barrier layer or in restitution following epithelial damage
What is associated with increased permeability of the epithelial of the gut?
IBD
What is considered as the primary abnormality in IBD?
Changes in the permeability
When bacterial components cross the mucosal barrier and come into direct contact with immune cells what does it induce?
Adaptive immune response
Where does IBD develop?
Terminal ileum and colon
What bacteria may cause IBD, although not proven?
M. Paratuberculosis
Measles virus (paramyxovirus)
L. Monocytogenes
What do commensal microflora suppress?
NF-KB
What triggers ulcerative colitis?
Epithelial Ags
Altered aerobic bacteria
What triggers crohn’s disease?
Anaerobic bacteria
What dietary component can stimulate IL-10 production in the LP?
Acetate produced from fermenting polysaccharides
Describe the pathogenesis of proinflammatory genes in the absence of Bacteroids?
Salmonella flagellin bind TLR5 intestinal epithelial cells
Activates IKB kinase (IKK) and NF-KB
NF-KB transcribes proinflammatory genes
Describe the pathogenesis of proinflammatory genes in the presence of Bacteroids?
Proinflammatory response attenuated
Induction of Peroxisome proliferation activated receptor (PPAR) –> exports activated NF-KB from nucleus
In what disease is only the colon involved?
UC
In what disease is continuous inflammation extending proximally from rectum?
UC
In what disease is there transmural inflammation?
CD
In what disease are there noncaseating granulomas?
CD
In what disease are there no granulomas?
UC
In what disease is pANCA positive?
UC
In what disease is ASCA positive?
CD
In what disease is bleeding common?
UC
In what disease do fistulae occur?
Crohn’s
Combination of ASCA (+) w/ (-) pANCA means what?
96% CD
What is characterized as Th1 and Th17 disease?
Driven by production of what?
CD
TNF/IFN-g and IL-17
What is characterized as Th2 disease?
Driven by production of what?
UC
IL-5 and IL-13 (made by NKT cells)
