Clusters of Differentiation

Question 1

CD3

Answer 1

T cell (general)

Question 2

CD4

Answer 2

T-helper

Question 3

CD8

Answer 3

Suppressor/cytotoxic T cell

Question 4

CD16

Answer 4

NK cells

Question 5

CD19

Answer 5

B cell

Question 6

CD20

Answer 6

B cell

Question 7

CD21

Answer 7

B cell

Question 8

CD18

Answer 8

Neutrophil adhesion molecules – important in LAD (leukocyte adhesion deficiency)

Question 9

CD80

Answer 9

B7 Ligand (costimulatory molecule on APC)

Question 10

CD34

Answer 10

Hemapoeitic stem cells (HSC)

Question 11

CD45R(0)

Answer 11

Memory B cell

Question 12

CD95

Answer 12

Fas —- death signaler for apoptosis (CTL killing)

Question 13

CD44

Answer 13

Receptor that binds to hyauluron, tethering t-cell to infection area in the peripheral tissues

Question 14

CD25

Answer 14

High affinity IL-2 receptor

-CD for T-Reg as well

Question 15

CD69

Answer 15

Binds to S1PR receptor, preventing T-cell from leaving lymph before 1) becoming functionally active and 2) before proliferating enough B-cells

Question 16

CD40

Answer 16

Co-stimulatory molecule on APC

Also a B cell?

Question 17

CD27

Answer 17

Memory B Cell

Question 18

CD56

Answer 18

NK Cell

Question 19

CD11

Answer 19

Neutrophil adhesion molecules – important in LAD (leukocyte adhesion deficiency)

Question 20

CD81

Answer 20

B-cell

Question 21

CD23

Answer 21

FcR-epsilon —- receptor on mast cells that recognizes IgE during Type I hypersensitivity – allergies

Question 22

CD22 receptor

Answer 22

• Inhibits BCR signaling —> defect = autoimmunity
• Phosphorylation by Lyn tyrosine kinase recruits SHP-1 tyrosine kinase, both of which activate CD22 and stop BCR signaling

Question 23

CD152

Answer 23

CTLA-4