Complements are manufactured in the liver. For additional information on complements, see this article . There are several hormones generated by components of the immune system. These hormones are known generally as lymphokines . It is also known that certain hormones in the body suppress the immune system.
Interleukins are another type of hormone generated by white blood cells.
For example, Interleukin-1 is produced by macrophages after they eat a foreign cell. The raised temperature of a fever is known to kill some bacteria. It is able to kill tumor cells, and it also promotes the creation of new blood vessels so it is important to healing. Interferons, like antibodies and complements, are proteins, and their job is to let cells signal to one another. When a cell detects interferon from other cells, it produces proteins that help prevent viral replication in the cell.