Final answer:
Interferon family cytokines are immune proteins that help control viral infections and tumor cells by signaling through Class 2 receptors, leading to inhibition of viral replication and activation of immune cells.
Step-by-step explanation:
The interferon family cytokines play a critical role in the immune response to viral infections and tumor surveillance. Interferons (IFNs) are proteins that are secreted by virus-infected cells to warn adjacent uninfected cells of the presence of a virus. They function by inhibiting viral replication within infected cells, promoting the destruction of RNA, reducing protein synthesis, and inducing apoptosis in infected cells.
Moreover, interferons activate various immune cells, including macrophages, which are essential for innate immunity. Receptors for interferon, known as Class 2 receptors, are responsible for transmitting the IFN signal into the cell, initiating a cascade of defensive immune responses.