[Interferon system in viral hepatitis].

Interferons are host-derived proteins produced by cells in response to viral and other stimuli. Three major types of interferons have been described: alpha, beta and gamma, which can be distinguished structurally, biochemically and antigenically. Interferon limits virus spread from focal sites of infection, shortens the period of viremia and decreases the severity of acute systemic infection. The problems of shortage, expense and lack of purity of natural interferons were overcome and now interferons are available for clinical trials. Interferons have shown to be a very promising group of agents against chronic viral hepatitis.