Leukocyte Adhesion and Circulation

Question 1

Name the 3 major selectins.

Answer 1

P-selectin (CD62P)
E-selectin (CD62E)
L-selectin (CD62L)

Question 2

Where is P-selectin expressed?

Answer 2

Endothelium activated by histamine or thrombin

Question 3

What is the ligand for P-selectin?

Answer 3

Sialyl Lewis X on P-selectin glycoprotein ligand 1 (PSGL-1) and other glycoproteins on neutrophils, monocytes, and T cells (effector, memory)

Question 4

Where is E-selectin expressed?

Answer 4

Endothelium activated by microbial products (LPS) and/or cytokines (TNF, IL-1) produced by dendritic cells and macrophages

Question 5

What is the ligand for E-selectin?

Answer 5

Sialyl Lewis X (e.g. cutaneous leukocyte antigen 1 (CLA-1)) on glycoproteins on neutrophils, monocytes, and T cells (effector, memory)

Question 6

Where is L-selectin expressed?

Answer 6

Neutrophils, monocytes, T cells (naive and central memory), and B cells (naive)

Question 7

What is the ligand for L-selectin?

Answer 7

Sialyl Lewis X on GlyCAM-1, CD34, MadCAM-1 (sialomucins) on endothelium (HEV), which are collectively called peripheral node addressin (PNAd)

Question 8

What are lectins?

Answer 8

Carbohydrate-binding proteins

Question 9

Name 4 major integrins.

Answer 9

1.Leukocyte function-associated antigen, LFA-1 (CD11aCD18)
2. MAC-1 (CD11bCD18)
3. Very late antigen 4, VLA-4 (CD49aCD29)
4. a4B7 (CD49dCD29)

Question 10

What is/are the ligand(s) for LFA-1 (CD11aCD18)?

Answer 10

ICAM-1 and ICAM-2 on endothelium

Question 11

What is/are the ligand(s) for MAC-1 (CD11bCD18)?

Answer 11

ICAM-1 and ICAM-2 on endothelium

Question 12

What is/are the ligand(s) for VLA-4 (CD49aCD29)?

Answer 12

VCAM-1

Question 13

What is/are the ligand(s) for a4B7?

Answer 13

VCAM-1 and MadCAM-1 on endothelium in gut and gut-associated lymphoid tissues