Interferons

Interferons are species-specific proteins that induce antiviral and antiproliferative responses in animal cells. They are a major defense against viral infections and abnormal growths (neoplasms). Interferons are produced in response to penetration of animal cells by viral (or synthetic) nucleic acid and then leave the infected cell to confer resistance on other cells of the organism.

Interferons are a group of proteins known primarily for their role in inhibiting viral infections and in stimulating the entire immune system to fight disease. Research has also shown that these proteins play numerous roles in regulating many kinds of cell functions. They can promote or hinder the ability of some cells to differentiate, that is, to become specialized in their function. They can inhibit cell division, which is one reason why they hold promise for stopping cancer growth. Recent studies have also found that one interferon may play an important role in the early biological processes of pregnancy. Although once thought to be a potential cure-all for a number of viral diseases and cancers, subsequent research has shown that interferons are much more limited in their potential. Still, several interferon proteins have been approved as therapies for diseases like chronic hepatitis, genital warts, multiple sclerosis, and several cancers.

The first interferon was discovered in 1957 by Alick Isaacs and Jean Lindenmann. During their investigation, the two scientists found that virus-infected cells secrete a special protein that causes both infected and noninfected cells to produce other proteins that prevent viruses from replicating. They named the protein interferon because it "interferes" with infection. Initially, scientists thought there was only one interferon protein, but subsequent research showed that there are many different interferon proteins.