012115 mucosal immunity

Question 1

fxn of M cell

Answer 1

to sample lumenal contents and deliver to Peyer’s patch

Question 2

what makes DCs and T cells tolerogenic in mucosa?

Answer 2

retinoic acid, TSLP, TGFbeta

they enhance MadCAM, CCL25, CCR9

Question 3

gut homing signals

Answer 3

alpha4beta7
CCR9
MadCAM
CCL25

Question 4

what drives the class switching in plasma cells to IgA?

Answer 4

TGFbeta

Question 5

class switching occurs through 2 mechanisms in gut-what are they?

Answer 5

T dependent

T independent

Question 6

retinoic acid and TGFbeta have what effect on T cells?

Answer 6

skews T cells to Th17 and regulatory T cells

Question 7

antigen vs immunogen

Answer 7

antigen-molecule bind to antibody or T cells

immunogen-moledulce induces immune response

Question 8

toleragen

Answer 8

molecule that induces immune unresponsiveness to subsequent doses

Question 9

what makes something an immunogen?

Answer 9

size-large
dose-intermediate
route-subcutaneous has increased immunogenicity compared to intragastric

composition-complex
adjuvant-bacteria
interaction with MHC complex-effective

Question 10

non responsiveness to food and microbiota is mediated by

Answer 10

regulatory T cells

Question 11

how do mucosal DCs regulate tolerance in the gut?

Answer 11

gut DCs take up antigens from gut (food or microbiota), travel to mesenteric lymph node, and present Ag to naive T cells

they produce retinoic acid and TGFbeta, driving differentiation of CD4 naive T cells to become regulatory T cells

Question 12

what three things predispose you to autoimmunity?

Answer 12

genetic suscpetibility
environmental trigger
uncontrolled immune response

Question 13

hypersensitivity

Answer 13

excessive or aberrant immune responses following challenge w antigen

Question 14

what genes is celiac dis associated w

Answer 14

HLA-DQ2, HLA-DQ8

Question 15

what type of hypersensitivity is celiac dis?

Answer 15

type IV (Th1 T cells and inflam response)

Question 16

what antibodies do you see in celiac dis?

Answer 16

anti gliadin
anti tTG
anti endomysium

Question 17

IBD

Answer 17

loss of tolerance to microbiota (due to mutations in Nod pattern recognition receptor genes, or mutations in autophagy genes)

Question 18

IBD is associated with what HLA types

Answer 18

HLA-DR, HLA-B27

Question 19

what type of hypersensitivity is IBD?

Answer 19

type IV (Crohn’s is Th1, UC is Th2)

Question 20

food allergy

Answer 20

NO loss of tolerance, NOT autoimmunity

Question 21

what type of hypersensitivity is a food allergy?

Answer 21

type I