interferon

n. protein produced by an animal cell in response to a virus (Chemistry)

Interferons (IFNs) are natural proteins produced by the cells of the immune system of most vertebrates in response to challenges by foreign agents such as viruses, bacteria, parasites and tumor cells. Interferons belong to the large class of glycoproteins known as cytokines. Interferons assist the immune response by inhibiting viral replication within other cells of the body.
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Interferon /in·ter·fer·on/ any of a family of glycoproteins, production of which can be stimulated by viral infection, by intracellular parasites, [more]Interferon - Community and Resources

Noun
1. an antiviral protein produced by cells that have been invaded by a virus; inhibits replication of the virus
(hypernym) antiviral, antiviral agent, antiviral drug
(hyponym) alpha-interferon

n. interferon, protein produced by an animal cell in response to a virus (Chemistry)