Final answer:
Interferons interfere with viral replication within cells and are virus-specific. They are not routinely used in nasal sprays for the common cold.
Step-by-step explanation:
Interferons are cytokines released by cells that have been infected with a virus. One of their main functions is to interfere with viral replication within cells. They work by signaling neighboring uninfected cells to destroy RNA, reduce protein synthesis, and undergo apoptosis. Interferons are virus-specific, meaning that an interferon produced against one virus may not protect cells against another virus. They are not routinely used in nasal sprays for the common cold.
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