Question

A virus has evolved to produce a soluble Interferon-gamma Receptor.  What cellular immune mechanism is the virus trying to directly prevent?

	A.	Activation of the alternative pathway of complement.
	B.	Mast cell degranulation.
	C.	V(D)J recombination.
	D.	Activation of macrophages

Answer 1

Option D-Activation of macrophages.

Production of soluble Interferon-gamma Receptor by the virus,Prevents the Binding of IFN-Gamma to cellular receptors.

Interferon Gamma (Type 2 Interferon) is a Cytokine that is essential for Innate and Adaptive Immunity.

These Interferon Gamma have 2 Functions-

1.Activation of macrophages

2.Induction of Class II MHC molecule expression.

This action is done when this Interferon Gamma binds to Interferon receptors 1 and 2 in the Cells.

Soluble IFN-Gamma Receptor produced by virus----Prevent IFN - gamma binding to its receptors in the cell----Prevents the acivation of Macrophages---Virus escpaes from Immune function of Cell