Which proteins are known to stimulate antiviral activity within cells?

Interferons are a group of signaling proteins that play a crucial role in the immune response, particularly in the defense against viral infections. When tissues are infected by viruses, they secrete interferons, which act as a warning system for neighboring cells. These proteins bind to specific receptors on these cells, triggering a range of responses that enhance the cells' antiviral defenses.

This includes the upregulation of various genes that inhibit viral replication, increase the presentation of viral antigens to T cells, and enhance the activity of immune cells such as natural killer cells and macrophages. This mechanism helps to establish an antiviral state within these cells, making them less susceptible to infection and aiding in the control and elimination of the virus.

Other options, such as interleukins, antibodies, and cytokines, each play significant roles in the immune response but do not directly induce the same strong antiviral state within cells as interferons do. For instance, interleukins are primarily involved in cell signaling and modulating the immune response rather than directly combating viral infections. Antibodies are crucial for identifying and neutralizing pathogens but rely on the immune system's continued response, while cytokines are broader signaling molecules that can influence various immune responses, not exclusively antiviral activity