Cell-Mediated Activation

Question 1

Distinguish between naïve, effector and memory lymphocytes.

Question 2

Describe the process of lymphocyte recirculation and to identify the cell adhesion molecules that mediate lymphocyte extravasation

Answer 2

L-Selectin on the T cell first binds with GlyCAM-1 on HEV which allows rolling. Chemokines activate LFA-1
(Integrin) which binds ICAM-1/2

Question 3

Diagram and label the molecules involved in the T cell antigen receptor complex

Answer 3

T cell receptor binds to MHC Class II and CD4 coreceptor binds to an invariant region on MHC class II

Question 4

Describe the cellular and molecular interactions between a
CD4+ T cell and a dendritic cell
CD8+ T cell and a dendritic cell

Question 5

Describe how the interactions between immune cells result in the activation of the T cells

Question 6

Discuss the key role of co-stimulatory signals provided by the CD28: CD80/86 interaction and the outcome if these signals are not received by the T cell.

Answer 6

B7.1 and B7.2 must interact with CD28 which leads to IL-2 ————> Proliferation

Question 7

Distinguish between the cytokines and transcription factors that promote differentiation of an activated T cell into a Th1,Th2 or Th17 cell

Answer 7

IL-12 and IFN-y = Th1

IL-4 = Th2

IL,1,6,23 and TGF-B = Th17