interferon

/in'teuhr fear"on/, n.
1. Biochem. any of various proteins, produced by virus-infected cells, that inhibit reproduction of the invading virus and induce resistance to further infection.
2. Pharm. Also called alpha-interferon. an interferon produced by genetically engineered bacteria and harvested for use against hairy cell leukemia.
[1957; INTERFERE + -ON1]

* * *

Any of several related proteins produced by all vertebrates and possibly some invertebrates.

They play an important role in resistance to infection. The body's most rapidly produced and important defense against viruses, they can also combat bacteria and parasites (see parasitism), inhibit cell division, and promote or impede cell differentiation. Interferon's effect is indirect
it reacts with susceptible cells, which then resist virus multiplication
in contrast to antibodies, which act by combining directly with a specific virus. Various types of interferons are distinguished by their characteristics as proteins and by which cells produce them. Some are now produced by genetic engineering. Initial hopes that interferon would be a wonder drug for a wide variety of diseases were deflated by its serious side effects, but a few rare conditions respond to it.

* * *

      any of several related proteins that are produced by the body's cells as a defensive response to viruses (virus). They are important modulators of the immune response (immune system).

      Interferon was named for its ability to interfere with viral proliferation. The various forms of interferon are the body's most rapidly produced and important defense against viruses. Interferons can also combat bacterial and parasitic infections, inhibit cell division, and promote or impede the differentiation of cells. They are produced by all vertebrate animals and possibly by some invertebrates as well.

      Interferons are categorized as cytokines (cytokine), small proteins that are involved in intercellular signaling. Interferon is secreted by cells in response to stimulation by a virus or other foreign substance, but it does not directly inhibit the virus's multiplication. Rather, it stimulates the infected cells and those nearby to produce proteins that prevent the virus from replicating within them. Further production of the virus is thereby inhibited and the infection is stemmed. Interferons also have immunoregulatory functions—they inhibit B- lymphocyte (B-cell) activation, enhance T-lymphocyte (T-cell) activity, and increase the cellular-destruction capability of natural killer cells.

      Three forms of interferon—alpha (α), beta (β), and gamma (γ)—have been recognized. These interferons have been classified into two types: type I includes the alpha and beta forms, and type II consists of the gamma form. This division is based on the type of cell that produces the interferon and the functional characteristics of the protein. Type I interferons can be produced by almost any cell upon stimulation by a virus; their primary function is to induce viral resistance in cells. Type II interferon is secreted only by natural killer cells and T lymphocytes; its main purpose is to signal the immune system to respond to infectious agents or cancerous growth.

      Interferons were discovered in 1957 by British bacteriologist Alick Isaacs and Swiss microbiologist Jean Lindenmann. Research conducted in the 1970s revealed that these substances could not only prevent viral infection but also suppress the growth of cancers in some laboratory animals. Hopes were raised that interferon might prove to be a wonder drug able to cure a wide variety of diseases, but its serious side effects, which include flulike symptoms of fever and fatigue as well as a decrease in the production of blood cells by the bone marrow, deflated expectations for its use against less serious diseases.

      Despite these setbacks, in the 1980s alpha interferon came into use, in low doses, to treat hairy-cell leukemia (a rare form of blood cancer) and, in higher doses, to combat Kaposi sarcoma, which frequently appears in AIDS patients. The alpha form also has been approved for treating the viral infections hepatitis B, hepatitis C (non-A, non-B hepatitis), and genital warts (condylomata acuminata). The beta form of interferon is mildly effective in treating the relapsing-remitting form of multiple sclerosis. Gamma interferon is used to treat chronic granulomatous disease, a hereditary condition in which white blood cells (leukocyte) fail to kill bacteria.

* * *


Universalium. 2010.

Look at other dictionaries:

  • INTERFÉRON — L’interféron, ou plutôt les interférons, constituent une famille de protéines sécrétées naturellement par l’organisme et douées d’un grand pouvoir biologique. Si on les a considérés au début comme un moyen de défense précoce et non spécifique de… …   Encyclopédie Universelle

  • Interferon — (IFN, von engl. to interfere eingreifen, sich einmischen) ist ein Protein oder Glykoprotein, das eine immunstimulierende, vor allem antivirale und antitumorale Wirkung entfaltet (siehe auch Zytokine). Es wird als körpereigenes Gewebshormon in… …   Deutsch Wikipedia

  • Interferon — Interféron Pour les articles homonymes, voir IFN. Les Interférons (IFN) sont des protéines (glycoprotéines de la famille des cytokines) naturellement produites par les cellules du système immunitaire, mais également par d autres types cellulaires …   Wikipédia en Français

  • Interferón β-1b — El interferón, es una proteína que se produce normalmente en el organismo, existiendo tres tipos α, β y γ. Estas proteínas tienen en común la regulación de la actividad del sistema inmunológico, modificando el comportamiento de los diversos tipos …   Wikipedia Español

  • interferon — INTERFERÓN, interferoni, s.m. (biochim.) Glicoproteină sintetizată în celulele animale după o infecţie virală, având proprietăţi antivirale. – Din engl. interferon, fr. interféron. Trimis de valeriu, 13.09.2007. Sursa: DEX 98  interferón s. m.,… …   Dicționar Român

  • interferón — m. inmun. Proteína antivírica que se sintetiza inespecíficamente por muchas células animales ante la presencia de un virus. Se produce en grandes cantidades ante virus poco virulentos, y en cambio, ante los muy virulentos la producción es escasa …   Diccionario médico

  • interferón — (Del ingl. interferon, der. de to interfere, intervenir, interferir). m. Bioquím. Glicoproteína sintetizada por células infectadas por virus, que inhibe la multiplicación de estos …   Diccionario de la lengua española

  • interferon — 1957, coined in English, so called because it interferes with the reduplication of viruses. From INTERFERE (Cf. interfere) + subatomic particle suffix ON (Cf. on) …   Etymology dictionary

  • interferon — interfèrōn m DEFINICIJA 1. fiziol. bjelančevina koju proizvode stanice organizma nakon virusne infekcije; sprečava razmnožavanje raznih vrsta virusa 2. farm. bjelančevina proizvedena od bakterija koje se razvijaju genetskim inženjeringom, služi… …   Hrvatski jezični portal

  • interferon — {{/stl 13}}{{stl 8}}rz. mnż I, D. u, Mc. interferonnie, biol. {{/stl 8}}{{stl 7}} przeciw wirusowa, złożona substancja białkowa wytwarzana przez leukocyty w zarażonych wirusami komórkach {{/stl 7}} …   Langenscheidt Polski wyjaśnień

  • interferon — ► NOUN ▪ a protein released by animal cells which inhibits virus replication …   English terms dictionary

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.