Immune [2]

Question 1

Peyer’s patches in the gut

Answer 1

favors the differentiation of Th0 into Tregs

• dont want crazy immune response in gut

Lots of Tfh that drive B cells to making IgA and mucus layer in gut is sterile

Question 2

IL-17 and IL-23 are common in areas of ____

Answer 2

inflammation

- hot heads

Question 3

IL-6 production

Answer 3

produced in response to stress/dmg

• 6 years olds

Question 4

The recognition of normal organisms in the gut is mostly carried out by the innate immune sys. What does NOD2 do?

Answer 4

NOD2 is a PRR (pattern recognition receptor)

• detects bacterial cell wall
• triggers cytokine production
• activation of NF-kB

Question 5

iTreg in gut is differentfrom Treg in thumus, how?

Answer 5

• iTreg induced by exposure to nl flora, prevent chronic inflammation that would result from Th1/2/17 recognizing nl commensal flora
• -> knocked out = IBD

Question 6

What comes first, Th1 or Th2?

Answer 6

Th1 comes first, bc if you cant kill it, you have Th2 as a last ditch reliance.
- Th1 is generally thought of immunity to parasites

Question 7

After a serious gut infxn what 2 directions can the immune sys take?

Answer 7

if you lucky

• infxn resolves and Tregs become dominant again
• Th1 against commensals decrease
• gut is now rich in memory cells, but do not nlly get activated

If you unlucky (risky alleles)
- unable to suppress Th1 against commensals –> IBD

Question 8

Celiac disease HLA type what? Why are these important MHC wise?

Answer 8

HLA DQ2, or HLA DQ8

• These class II MHC are uniquely able to present peptide derived from gliadin to Th1/Th17 cells

(nlly these peptides are too bulky to fit in MHC ag presenting grooves)

Question 9

Dermatitis herpetiformis can result from ab to which enzyme?

Answer 9

Antibody to TTG2

- chronic skin infxn

Question 10

How does Antibody to TTG2 result in Celiacs?

Answer 10

TTG2 tries to cleave highly branched/charged gliadin, and may get “stuck” and become unable to release its substrate.

WAIT NOW YOU HAVE A FOREIGN MOLECULE LINKED TO A SELF MOLECULE! yes. yes you do. You’re fucked.

B cell thats anti-TTG2 takes up the complex and presents foreign gliadin peptides to Tfh, which helps the B cell make Ab to TTG2. (IgA)

Question 11

Is celiacs disease itself autoimmune?

Answer 11

No, but dermatitis herpetiformis is.

Question 12

5-50% of ______ pts have arthritis in 1 or more joints

Answer 12

IBD

• ask if they have bloody poop
• • diarrhea?

Question 13

requirements for dx of non-celiac gluten sensitivity

Answer 13

1. negative blood test for celiac dis. AND no sign of dmg on an intestinal biopsy
2. Symptom improvement when gluten is removed from diet
3. Recurrence of sx when gluten is reintroduced
4. , No other explanations for sx.