Final answer:
The statement about Type I interferon being barely detectable in healthy individuals but abundant during infection is true. Interferons are cytokines that respond to viral infections by signaling nearby cells to increase their resistance, thereby limiting viral replication and spread.
Step-by-step explanation:
The statement that Type I interferon is barely detectable in healthy individuals' blood, but becomes abundant during infection is true. Interferons, especially Type I, play a critical role in the body's defense mechanism against infections. They are a class of cytokines, which are small proteins released by cells in response to the presence of pathogens, particularly viruses. When a cell is infected by a virus, it will release interferons to signal nearby cells of the viral presence. These neighboring cells respond by making changes in gene expression that boost their resistance to infection, thereby making it harder for the virus to replicate and spread.
Interferons serve multiple roles in the immune system, including activating macrophages and enhancing the function of T cells. They are particularly useful against infections caused by viruses, where they interfere with viral replication and augment the immune response. Considering this, interferon levels can be elevated in the blood during viral infections, acting as an indicator and a means to control the spread of the virus.