GI Microflora In Health And Disease (Putin)

Question 1

What is the primary abnormality in IBD?

Answer 1

Increased permeability of the epithelia of the gut

Question 2

Where does IBD usually develop?

Answer 2

In areas of HIGH BACTERIAL concentration such as TERMINAL ILEUM and COLON

Question 3

Commensalism microflora suppress the ___ pathway

Answer 3

NF-kB

Question 4

Epithelial ags and altered aerobic bacteria trigger ___

Anaerobic bacteria trigger

Answer 4

UC

CD

Question 5

Microbe-modified dietary components can stimulate ___ production regulating metabolic activity in the lamina propria

Answer 5

IL-10

Question 6

MAMPs/PAMPs signaling via __ can modify local mucosal immunity

Answer 6

TLRs

Question 7

Commensalism microflora controls inflammation via inhibition of __

Answer 7

NF-kB

Question 8

Salmonella enteritidis binds to this TLR

Answer 8

TLR5

Question 9

If you add bacteroides thetaiotaomicron with salmonella enteridis, what transcription factor is activated to resist activation of inflamm responses?

Answer 9

PPARy

Question 10

In the absence of commensalism Bacteroides, salmonella flagellum binds to __ intestinal epithelial cells, activates __ kinase and get nuclear translocation of __ that mediates proinflammation

Answer 10

TLR5

IkB (IKK)

NF-kB

Question 11

WHat Abs are found in UC? What about Crohns?

Answer 11

UC–> pANCA positive

CD –> ASCA positive

Question 12

Crohns disease is characterized as a _ disease driven by the production of TNF/IFN-y and IL-17

Answer 12

Th1 and Th17

Question 13

What are the cytokines produced by Th1? Th17?

Answer 13

Th1–>TNF/IFN-y

Th17–> IL-17

Question 14

UC is often viewed as a __ disease because of increased mucosal expression of IL-5 and IL-13 produced by NKT cells

Answer 14

Th2

Question 15

What cytokine converts activated T cells to Th1 cells?

Answer 15

IL-12

Question 16

What cytokine converts an activated T cell to Th2 cell?

Answer 16

IL-4

Question 17

What cytokine converts an activated T cell to Th17 cell?

Answer 17

IL-6 and IL-23

Question 18

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

Answer 18

IL-23

Question 19

CD80/86 is found on a __

CD20 is found on a __

CD3 is found on a ___

CTLA4/CD28 is found on a ___

Answer 19

DC

B cell

Th cell

Th cell

Question 20

CD25 is a __ receptor

Answer 20

IL2

Question 21

What cytokine activates NKT cells?

Answer 21

IL13

Question 22

Treg cells produce this cytokine:

Answer 22

IL10 (anti-inflamm)

Question 23

Stromal cells release this cytokine for activation of B cells:

Answer 23

IL-11

Question 24

What cytokines are associated with the Th1 and Th17 response in Crohns disease?

Answer 24

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

Question 25

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

Answer 25

TGF-b

Question 26

Which cytokines are upregulated by Tregs? Downregulated?

Answer 26

Upregulated=IL-10, TGF-b

Downregulated=IL-12, CD80/86, CD40

Question 27

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

Answer 27

Chr 16

CARD15/NOD2

Question 28

CARD15 is what type of receptors?

CARD15/NOD2 recognizes molecules containing the specific structure called ___

Answer 28

IC pathogen recognition receptor (PPR)

Muramyl dipeptide (MDP) –> triggers activation of NF-kB

Question 29

CARD15/NOD is primarily expressed in ___

Answer 29

Monocytes/macrophages