INTRODUCTION TO CELLULAR ADHESION MOLECULES – Dr. Block

Question 1

Name 4 categories of cellular adhesion molecules.

Answer 1

Integrins
Immunoglobulin superfamily
Dadherins
Selectins

Question 2

Which category of cellular adhesion molecules are involved in transmitting signals from both the inside of cells to the outside as well as from the outside of cells to the inside?

Answer 2

Integrins.

Question 3

Which category of cellular adhesion molecules are involved in adherens junctions between cells, for example in the periodontal ligament?

Answer 3

Cadherins

Question 4

Give abbreviations for 3 adhesion molecules from the immunoglobulin superfamily and tell the origin of the abbreviation.

Answer 4

NCAM = neural cell adhesion molecule
PECAM = platelet-endothelial cell adhesion molecule
VCAM = vascular cell adhesion molecules

The abbreviation is due to their similarity in structure to the immunoglobulins

Question 5

What cellular adhesion molecules primarily interact with carbohydrate ligands?

Answer 5

Selectins

Question 6

Name 4 diseases in which cellular adhesion molecules are involved.

Answer 6

• Rheumatoid arthritis is due to overexpression of VCAMs.
• Psoriasis is due to a form of an integrin being in the suprabasal layer rather than the basal layer
• Pemphigus vulgaris or phmphigus foliaceus due to auto-antibodies interacting with desmoglein.

Rhinovirus uses intercellular adhesion molecules (ICAM )to infect the nasal epithelium

• von Willebrand disease due to expression of P-selectin.

Question 7

What is the major role of selectins?

Answer 7

Causing leukocytes to roll along the surface (biological braking mechanism).

Question 8

Where are P-selectin stored in platelets and endothelial cells?

Answer 8

alpha granules (in platelets)
Weibel-Palade bodies (in endothelial cells)

Question 9

Tumor cells that lose …. become invasive and motile.

Answer 9

E-cadherin

Question 10

What is the normal function of E-Cadherin?

Answer 10

to control metastatic and invasive behavior. Hence why loss of it causes tumor cells to become invasive and motile.