Chapter 8: Cell-Mediated Immunity

Question 1

Where do effector T cells travel?

Answer 1

leave secondary lymphoid tissue, enter into circulation, and travel to the site of the infection.

Question 2

Perforin function?

Answer 2

creates pores in membrane of target cell

Question 3

Granzyme function

Answer 3

serine protease that enter the cell inducing the activation of caspases which activate the “death” domain

Question 4

Do activated CTLs express Fas or FasL on membrane?

Answer 4

FasL

Question 5

How does FasL and Fas interact to produce cell death?

Answer 5

caspases are induced and death results

Question 6

4 phases by which CTLs kill target cells.

Answer 6

1. Attachment of the target cell (mediated by TCR, CD8, and LFA-1 integrin)
2. Activation (cytoskeletal rearrangement to concentrate granules against attached target cell
3. Exocytosis of granule contents (perforin and granzymes)
4. Detachment from the target cell

Question 7

What is the ADCC?

Answer 7

final mechanism of cytotoxicity which bridges humoral and cell-mediated effector systems in the body

When IgG is specifically bound to a target cell, the cytotoxic cells (NK cells, macrophages, neutrophils, and eosinophils) can bind to the Fc “tail” and subsequently cause lysis of the target cell

Question 8

What are some mechanisms of target cell killing when it comes to ADCC?

Answer 8

1. lytic enzymes
2. tumor necrosis factor
3. perforin/granzymes