Immunology

Question 1

Viral infection of host cells induces the production of _____.

Answer 1

type 1 interferons (alpha and beta ** NOT GAMMA**)

Question 2

What is the function of type 1 interferons

Answer 2

selective inhibition of protein synthesis in virally infected cells ONLY (changes only take place with dsRNA present)

Accomplished via upregulation of

1) RNase L - endonuclease that degrades all RNA in the cell
2) protein kinase R - inactivates eIF-2, inhibiting translation initiation

autocrine/paracrine signaling => also increases apoptosis

Question 3

How do type 1 interferons faciliate cytoxic immunity?

Answer 3

interferon alpha and beta induce expression if MHC class I and stimulate cytotoxic killing by NK cells and cytotoxic T cells

Question 4

What effect does interferon gama have on host cells/host immune cells?

Answer 4

Enhances differentiation into Th1 subset Helper T cells
Increases expression of MHC II on APCs
improves intracellular killing ability of macrophages