Eosinophils, Basophils, Mast Cells

Question 1

Eosinophils differentiate from

Answer 1

myeloid progenitor, (require IL-5)

Question 2

Eosinophils exits bone marrow under influence of

Answer 2

IL-5 and Chemokine CCL11/ Eotaxin

Question 3

CCL11 is secreted by

Answer 3

epithelial cells and fibroblats

Question 4

circulating eosinophils make up

Answer 4

2-5% of circulating leukocytes

Question 5

half life of eosinophil

Answer 5

8-10 hours

Question 6

eosinophila

Answer 6

increase in circulating eosinophils

Question 7

6 steps in immune response to helminths

Answer 7

1. activation of T cells and B cells specific for helminths (T-cells help B-cells) 2. activated B-cells differentiate to plasma cells that secrete IgE antibodies specific for helminths 3. Specific antibodies bind (via FAB region) to helminth 4. constant region (Fc-epsilon) protrudes 5.Eosinophils express Fc-epsilon-RII that bind to Fc-epsilon attached to helminth 6. Eosinophils secrete major basic protein(MBP) and eosinophil cationic protein (ECP) that are toxic to helminths

Question 8

Eosinopihlia is associated with

Answer 8

atopic dermititis, allergies, astham whose basis is allergy

Question 9

Basophils and mast cells differentiate from

Answer 9

myeloid progenitor

Question 10

basophils mature in

Answer 10

bone marrow (requires IL-3)

Question 11

mast cells leave bone marrow as

Answer 11

immature cells

Question 12

mast cells enter circulation and

Answer 12

egress into tissues where they mature

Question 13

cell surface receptors for basophils and mast cells

Answer 13

Fc-epsilon-RI(B2 Fc-epsilon), C3a/C4aR, C5aR(both are ligands to C3a/C4a, C5a)

Question 14

receptor-ligand interactions on basophils and mast cells are

Answer 14

hydrophilic and hydrophobic, reversible

Question 15

half life of bound IgE is

Answer 15

weeks to months

Question 16

Half-life of IgE in serum is

Answer 16

2 days

Question 17

half life of circulating basophils

Answer 17

2.5 days

Question 18

circulating % of basophils

Answer 18

less than 1% of all leukocytes

Question 19

half life of mast cells

Answer 19

varies with tissue compartment

Question 20

activation of basophils and mast cells leads to

Answer 20

degranulation and histamine release and secretion of IL-4 and IL-5

Question 21

during inflammation, histamine binds to

Answer 21

cognate receptor on endothelial cells

Question 22

histamine binding during inflammation leads to

Answer 22

translocation of p-selectin(adhesion molecule) from the cytosol to be expressed on cell surface.

Question 23

during inflammation endothelial cell vascular permeability is

Answer 23

increased

Question 24

when IgE binds to helmith there is a

Answer 24

conformational change in the Fc Region binding of antigen which may explain why they can interact with Fc-epsilon receptors

Question 25

Fc-epsilon-R and Fc-epsilon binding is

Answer 25

noncovalent and relies on ionic and hydrophobic interatcion. it is reversible.

Question 26

Bound IgE antibodies are available for

Answer 26

binding specific for their FAB region.

Question 27

when two IgE molecules of the same specificity are sufficientyl close together

Answer 27

the antigen binding results in crosslinking and degranulation of the basophil or mast cell. this releases histamine and other immune mediators from the granules

Question 28

ligands for C3a/4aR and C5aR (C3a, C5a) following

Answer 28

complement activation