Macrophages

Question 1

What type of cells are macrophages? What are they derived from?

Answer 1

Phagocytic leukocytes

Blood monocytes

Question 2

Where do macrophages reside?

Answer 2

In tissues (under skin, in lungs and around intestines)

Question 3

Are macrophages professional phagocytes?

Answer 3

Yes

Question 4

What are the 3 activation states of macrophages?

Answer 4

1. Resting
2. Primed
3. Hyperactive

Question 5

What is job of macrophages in resting state? Do they contain lots of MHC II?

Answer 5

Collects debris from tissues from phagocytosis and eliminates apoptotic cells

Contains very little MHC II

Question 6

Do macrophages express MHC II?

Answer 6

Yes

Question 7

What is job of macrophages in primed state? Do they express MHC II?

Answer 7

Take up larger objects by phagocytosis

Expresse increased levels of MHC II

Question 8

What are macrophages primed by?

Answer 8

IFN-y (cytokine interferon gamma)

Question 9

What is the cytokine ‘interferon gamma’ produced by?

Answer 9

Nk cells and T helper cells

Question 10

How do macrophages become hyperactive?

Answer 10

Stimulated with both IFN-y and LPS

Question 11

What is LPS produced by?

Answer 11

Gram-negative bacteria

Question 12

What is function of hyperactive macrophages?

Answer 12

Stop proliferation, become larger and increase their rate of phagocytosis

They also produce cytokines

Question 13

What cytokines do hyperactive macrophages produce?

Answer 13

TNF and IL-1