T1 L6, Adaptive immunity 3

Question 1

Which cells determine which peptides will be presented on class I or class II MHC during initial activation?

Answer 1

Antigen presenting cells (APC’s)

Question 2

What are the 2 antigen processing pathways?

Answer 2

Endogenous: antigens presented on class I MHC molecules to CD8 T-cells (cytotoxic)

Exogenous: endosomes presented on class II MHC molecules to CH4 T-cells (Helper)

Question 3

What do cytotoxic T-cells do?

Answer 3

They kill infected cells and tumour cells

Question 4

What are CTL’s?

Answer 4

Cytotoxic T lymphocytes

Question 5

What are TAP proteins for?

Answer 5

Transporters associated with Antigen Processing proteins

TAP pump peptides across a membrane

Question 6

What does the herpes simplex virus (HSV) do to TAP proteins?

Answer 6

It inhibits TAP proteins so their peptide can’t be transferred out of the ER

Question 7

How do Leishmania and mycobacteria evade class II MHC?

Answer 7

They prevent lysosome fusion so they can’t be digested