Immunologic tolerance and autoimmunity

Question 1

Generation and maintenance of Tregs are dependent on which cytokines?

Answer 1

IL-2 and TGF-B, which stimulates expression of FOXP3

Question 2

What are some mechanisms of action of Tregs?

Answer 2

1) CTLA-4-mediated inhibition of costimulation
2) Production of immunosuppressive cytokines IL-10 and TGF-B
3) Consumption of IL-2

Question 3

What are four functions of TGF-B?

Answer 3

1) Inhibition of proliferation and effector functions of T cells, activation of macrophages
2) Stimulates development of FOXP3+ Tregs, Th17 cells
3) Promoting class switching to IgA
4) Promotes tissue repair after local immune and inflammatory reactions subside

Question 4

What are two functions of IL-10?

Answer 4

1) Inhibits production of IL-12 by activated DCs and macrophages
2) Inhibits expression of costimulators and class II MHC molecules on DCs and macrophages

Question 5

Which virus contains a gene homologous to IL-10?

Answer 5

EBV