7 - Effector T lymphocytes

Question 1

How do T-cells affect the functions of other cells?

Answer 1

the produce cytokines and chemokines

Question 2

What do APCs do?

Answer 2

chew up the pathogen, express it on an MHC and present it to a T-cell

Question 3

Which location do T-cells art at and where do they migrate to?

Answer 3

• starts in the bone marrow
• mature in the thymus
• move into the lymph nodes
• once they have recognised an antigen on an APC (DC), they migrate migrate into the circulation and goes tot he site of infection

Question 4

What is the molecular address system?

Answer 4

• chemokine gradient

- adressins and integrins (these allow the cells to move out of vessels)

Question 5

Define apoptosis and necrosis

Answer 5

apoptosis - programmed cell death

necrosis - inflammatory cell death

Question 6

What are the 2 waves in a classic allergic response?

Answer 6

acute mast cell driven wave

T cells driven phase

Question 7

If the antigen isn’t eradicated in delayed type hypersensitivity, what is the result?

Answer 7

chronic stimulation and granuloma formation

Question 8

What cells/molecules are involved in delayed type hypersensitivity?

Answer 8

helper T-cells
macrophages

T helper cell cause pronounced secretion of cytokines (act as inflammatory mediators and activate macrophage to secrete their potent mediators)

NOT antibodies

Question 9

What causes immediate hypersensitivity?

Answer 9

mast cell degranulation

Question 10

What is the difference between the types of antigens taken up by B-cells and DCs?

Answer 10

• B-cells only take up antigens that they recognise

- DCs take up a large variety of antigens

Question 11

What are the 2 subsets of memory T-cells?

Answer 11

• effector memory - memory is local to the site of infection
• central memory - goes back to the spleen or lymph nodes

central memory is longer lasting but is a slower response to activate