Leukocyte Trafficking

Question 1

recruitment of immune cells into tissues occurs in _

Answer 1

post-capillary venules

Question 2

post-capillary venules

Answer 2

thinnest walls and lowest BP

Question 3

recognition of bacteria by macrophages stimulates _

Answer 3

expression of adhesion molecules on endothelial cells

Question 4

selectins

Answer 4

slow rolling

Question 5

ICAM-1

Answer 5

adhesion (binds beta-2 integrin on immune cell)

Question 6

chemokine receptor on immune cells binds _

Answer 6

chemokine on endothelium for leukocyte activation –> changes conformation of beta-2 integrin to allow it to bind to ICAM-1

Question 7

chemoattractants on endothelial cell surface

Answer 7

chemokines, platelet activating factor, TNF-alpha, IL-1b, IFN-gamma

Question 8

Which chemoattractants guide immune cells to site of inflammation?

Answer 8

LTB4, IL-8, C3a and C5a

Question 9

selectins bind _

Answer 9

mucin-like CAMs

Question 10

Ig-superfamily CAMs bind _

Answer 10

integrins (mainly LFA-1 and Mac-1)

Question 11

Ig-superfamily CAMs

Answer 11

ICAM-1,2,3 and LFA-2,3

Question 12

mucin-like CAMs

Answer 12

CD34, glyCAM-1

Question 13

post-capillary venules in lymph nodes

Answer 13

HEV (high endothelial venules)

Question 14

immature DC pathway

Answer 14

internalize antigens –> lose E-selectin binding –> travel through afferent lymph into lymph node –> move to paracortical region –> present antigen and die

Question 15

naive T cells

Answer 15

express L-selectin which binds PNAds in HEV

Question 16

L-selectin on T cells binds _

Answer 16

GlyCAM and CD34 and PNAd (on HEVs) for slow rolling

Question 17

chemokine activation of T cells

Answer 17

CCL21 (SLC) binds CCR7 on T cells

Question 18

LFA-1 on T cells binds _

Answer 18

ICAM-1

Question 19

chemokines for diapedesis

Answer 19

CXCL12 on endothelium binds CXCR4 on T cells

Question 20

CCL21 (SLC)

Answer 20

binds CCR7 on T cells for integrin activation

Question 21

CCL19

Answer 21

also binds CCR7 but not on HEVs

Question 22

What happens after T cell encounters its ligand (antigen) in the lymph node?

Answer 22

it will lost the ability to leave and begin to proliferate in T cell zones –> will then express CXCR5 allowing them to migrate to primary follicles to activate B cells

Question 23

What happens once a cell is an effector T cell?

Answer 23

it loses its expression of L-selectin and can no longer enter HEV

Question 24

central memory T lymphocytes

Answer 24

re-express L-selectin and localize to secondary lymphoid organs

Question 25

L-selectin is _

Answer 25

CD62L