A brief history of the use of interferons as treatment of multiple sclerosis.

Interferons (IFNs) are a family of glycoproteins that are naturally secreted by certain cells in response to viral infection. The naturally occurring IFNs confer protection on other cells, preventing them from becoming infected, a phenomenon referred to as "virus interference" by Isaacs and Lindenmann in the first description of these proteins. In addition to their antiviral properties, the IFNs also have complex immunomodulatory, antiproliferative, and hormonelike activities, which are not completely understood.