Practice #5 cell migration

Question 1

Types of kinesis

Answer 1

Kinesis- random motion

1. Chemokinesis (with a net direction)
2. Orthokinesis (with constant speed)
3. Klinokinesis (with constant frequency)

Question 2

Types of Taxis

Answer 2

Taxis- vectorial motion (guided by concentration gradient)

1. Chemotaxis
2. Haptotaxis (surface concetration gradient)
3. Necrotaxis (necrotic cell debris gradient)

Question 3

Chemotaxis

Answer 3

Migratory response of cells elicited by soluble molecules in the environment of the cells

Question 4

Professional chemoattractants

Answer 4

Chemokines,
C3a C5a
Bacterial N formyl peptides
AA products

Question 5

primarily not chemoattractants but effective molecules

Answer 5

Amino acids, oligopeptides, peptide hormones
Steroids
Volatile oils
Synthetic substances

Question 6

How does the tissue infiltrated lymphocytes or DC know to return to the lymph node?

Answer 6

They express CCR7 upon activation

The ligand for CCR7 is CCL19/CCL21 constantly produced by the lymph node

Question 7

Diseases caused by impaired chemotaxis

Answer 7

Chediak Higashi syndrome

Kartagener syndrome

Question 8

Toxic materials effecting chemotaxis

Answer 8

Decrease: Hg, Cr salt, O3
Increase: asbestos, benzpyrene

Question 9

Diseases in which chemotaxis is impaired

Answer 9

AIDS
Multiple sclerosis
Hodgkin lymphoma
Male infertility

Question 10

Diseases in which chemotaxis is enhanced

Answer 10

Inflammation
Atherosclerosis
Arthritis
Psoriasis
Reperfusion injury
Metastatic tumors

Question 11

Blocking of HIV infection of cells by inhibiting chemotaxis

Answer 11

M tropic HIV strains bind to CCR5
Inhibitors of CCR5: MIP1alpha and beta, RANTES

T tropic HIV strains bind to CXCR4
Inhibitor of CXCR4: SDF1