Question

Variola virus, the virus known to cause small pox, produces soluble TNF alpha receptors (meaning that these receptors are secreted by the virus). What advantage does the production of a TNFalpha receptor have for avoiding immune response?

i. TNF alpha represents a family of soluble cytokines. By producing soluble receptors that bind to this cytokines, the cytokine effector response is eliminated and only a limited immune response will occur
ii. TNF alpha receptors bind to cells of the immune system and prevent the release of cytokines.
iii. TNF alpha receptors block transcription within infected cells so that new virus particles cannot be made.
iv. TNF alpha receptors bind to cytotoxic T cells, preventinglysis of infected cells.
v. TNF alpha receptors allow an infected cell to become infected by more than one variola virus particle

Answer 1

i. TNF alpha represents a family of soluble cytokines. By producing soluble receptors that bind to this cytokines, the cytokine effector response is eliminated and only a limited immune response will occur

Step-by-step explanation:

Cytokines represent a broad category of small proteins which are secreted by specific cells of the immune system. These molecules (cytokines) indicate instructions and mediate communication between immune and non-immune cells. The Tumour Necrosis Factor-alpha (TNF-alpha) is a cytokine that exhibits pleiotropic effects on cells (e.g., cell proliferation, cell death, etc). Cytokine antagonists are molecules capable of inhibiting cytokine activity by interacting with their receptors, by altering their production, or by directly binding to cytokines and thereby preventing their functions. The variola virus is a poxvirus, which encodes viral TNF receptors (vTNFRs) capable of blocking the activity of proinflammatory cytokines and thus avoids an effective host immune response.