Ab Mediated Immune Responses: Humoral Immunity

Question 1

resting mature naive B cells express 6 things

Answer 1

BCR - IgM, IgD, Igalpha and Igbeta 
Co-BCR - CD19, CD81, CR22 (CD21) 
HLA-class II 
CD40 
CD45R(A) 
CD20

Question 2

In the secondary lymphoid tissue, B cells recieve what from follicular dendritic cells?

Answer 2

Survival signals - without these naive b cells would die within weeks

Question 3

B cells enter LN throug h

Answer 3

HEV

Question 4

in order to provide first signal to B cells, Ag must

Answer 4

crosslink 2 or more BCR

activates Igalpha and Igbeta ITAMs

Question 5

Igalpha and Igbeta associate with BCR and serve what purpose?

Answer 5

signaling, contain ITAM domains
interaction with BCR causes src kinases to phosphorylate these ITAMs –> Syk recruited –> gets phosphorylated –> PLCgamma - DAG - Ras/Rac GTP

Question 6

BCR activation induces what transcription factors

Answer 6

Myc
NFAT
NF-KB
AP-1

Question 7

second signal for b cell activation

Answer 7

CR2 (CD21) binds bound C3d on Ag and enhances BCR signaling from Igalpha and Igbeta
apparently TLRs can do the same thing

Question 8

After Ag recognition, B cells migrate

Answer 8

to the edge of the follicular zone to interact with helper T cells

Question 9

Th cells can provide secondary signal to B cells through

Answer 9

T cell CD40L binding CD40 receptor on B cell for T dependent Ag