interferon

proteins released from CELLS infected with a VIRUS that restrict, or interfere with, the growth of that virus. They limit the growth of cells, hence their use in cancer treatment (which is as yet of indeterminate value). There are three human interferons: a from white blood cells ( LEUCOCYTES ), ╬▓ (b) from CONNECTIVE TISSUE and g from lymphocytes (see INTERLEUKIN ). Sufficient quantities of interferon can now be produced by GENETIC ENGINEERING .