GI Microflora In Health And Disease (Putin) Flashcards
What is the primary abnormality in IBD?
Increased permeability of the epithelia of the gut
Where does IBD usually develop?
In areas of HIGH BACTERIAL concentration such as TERMINAL ILEUM and COLON
Commensalism microflora suppress the ___ pathway
NF-kB
Epithelial ags and altered aerobic bacteria trigger ___
Anaerobic bacteria trigger
UC
CD
Microbe-modified dietary components can stimulate ___ production regulating metabolic activity in the lamina propria
IL-10
MAMPs/PAMPs signaling via __ can modify local mucosal immunity
TLRs
Commensalism microflora controls inflammation via inhibition of __
NF-kB
Salmonella enteritidis binds to this TLR
TLR5
If you add bacteroides thetaiotaomicron with salmonella enteridis, what transcription factor is activated to resist activation of inflamm responses?
PPARy
In the absence of commensalism Bacteroides, salmonella flagellum binds to __ intestinal epithelial cells, activates __ kinase and get nuclear translocation of __ that mediates proinflammation
TLR5
IkB (IKK)
NF-kB
WHat Abs are found in UC? What about Crohns?
UC–> pANCA positive
CD –> ASCA positive
Crohns disease is characterized as a _ disease driven by the production of TNF/IFN-y and IL-17
Th1 and Th17
What are the cytokines produced by Th1? Th17?
Th1–>TNF/IFN-y
Th17–> IL-17
UC is often viewed as a __ disease because of increased mucosal expression of IL-5 and IL-13 produced by NKT cells
Th2
What cytokine converts activated T cells to Th1 cells?
IL-12
What cytokine converts an activated T cell to Th2 cell?
IL-4
What cytokine converts an activated T cell to Th17 cell?
IL-6 and IL-23
This cytokine is produced by APCs, regulates activity of macrophages and DCs, mice that are deficient of this cytokine do NOT have DTH, is closely related to IL-12 and regulates Th1 cell responses, and stimulates T cells to produce IL-17 but not IFN-y or IL-4
IL-23
CD80/86 is found on a __
CD20 is found on a __
CD3 is found on a ___
CTLA4/CD28 is found on a ___
DC
B cell
Th cell
Th cell
CD25 is a __ receptor
IL2
What cytokine activates NKT cells?
IL13
Treg cells produce this cytokine:
IL10 (anti-inflamm)
Stromal cells release this cytokine for activation of B cells:
IL-11
What cytokines are associated with the Th1 and Th17 response in Crohns disease?
IL-12 for Th1 which secretes IFN-y
IL-23 for Th17 which secretes IL-17
Macrophages also activated by IL-23 and can secrete TNF
Limited expression of pro-inflamm cytokines by APCs and an excess of ___ result in differentiation of naive T cells into Treg cells which suppress Th1, Th2, and Th17 responses
TGF-b
Which cytokines are upregulated by Tregs? Downregulated?
Upregulated=IL-10, TGF-b
Downregulated=IL-12, CD80/86, CD40
THe IBD-1 gene is a susceptibility locus found on chromosome __. Its locus contains __ genes and an individual homozygous for the susceptible variant have more than 20-fold increased risk of developing CD
Chr 16
CARD15/NOD2
CARD15 is what type of receptors?
CARD15/NOD2 recognizes molecules containing the specific structure called ___
IC pathogen recognition receptor (PPR)
Muramyl dipeptide (MDP) –> triggers activation of NF-kB
CARD15/NOD is primarily expressed in ___
Monocytes/macrophages
