Dictionary:
hap·ten (hăp'tĕn')  also hap·tene
|
[German : Greek haptein, to fasten + German -en, n. suff. (from Greek -ēnē, -ene).]
haptenic hap·ten'ic adj.| 5min Related Video: hapten |
| Dental Dictionary: hapten |
A nonproteinaceous substance that acts as an antigen by combining with particular bonding sites on an antibody. Unlike a true antigen, it does not induce the formation of antibodies. A hapten bonded to a carrier protein may induce an immune response. Also called hap-tene.
| Medical Dictionary: hap·ten |
A substance that is capable of reacting with a specific antibody but cannot induce the formation of antibodies unless bound to a carrier protein or other molecule. Also called incomplete antigen, partial antigen.
| Wikipedia: Hapten |
 |
This article needs additional citations for verification. Please help improve this article by adding reliable references. Unsourced material may be challenged and removed. (December 2008) |
A hapten is a small molecule that can elicit an immune response only when attached to a large carrier such as a protein; the carrier may be one that also does not elicit an immune response by itself. (In general, only large molecules, infectious agents, or insoluble foreign matter can elicit an immune response in the body.) Once the body has generated antibodies to a hapten-carrier adduct, the small-molecule hapten may also be able to bind to the antibody, but it will usually not initiate an immune response; usually only the hapten-carrier adduct can do this. Sometimes the small-molecule hapten can even block immune response to the hapten-carrier adduct by preventing the adduct from binding to the antibody.
The concept of haptens emerged from the work of Karl Landsteiner[1] [2] who also pioneered the use of synthetic haptens to study immunochemical phenomena.[3]
Contents |
A well-known example of a hapten is urushiol, which is the toxin found in poison ivy. When absorbed through the skin from a poison ivy plant, urushiol undergoes oxidation in the skin cells to generate the actual hapten, a reactive molecule called a quinone, which then reacts with skin proteins to form hapten adducts. Usually, the first exposure only causes sensitization, in which there is a proliferation of effector T-cells. After a second exposure later, the proliferated T cells can become activated, generating an immune reaction, producing the typical blisters of poison ivy exposure.
Some haptens can induce autoimmune disease. An example is hydralazine, a blood pressure-lowering drug that occasionally can produce drug-induced lupus erythematosus in certain individuals. This also appears to be the mechanism by which the anaesthetic gas halothane can cause a life-threatening hepatitis, as well as the mechanism by which penicillin-class drugs causes autoimmune hemolytic anemia.
Other haptens that are commonly used in molecular biology applications include fluorescein, biotin, digoxigenin, and dinitrophenol.
|
||||||||||||||||||||||||||||||||||
This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)
 | carrier molecule (immunology) |
| dinitrochlorobenzene |
| hapten, haptene |
 | What are haptens? Read answer... |
| What are different haptens found in the body? Read answer... |
 | What is a hapten? |
| Is cephalexin a hapten? |
| What hapten to the Coromandel striped gecko? |
Copyrights:
 |
 | Dictionary. The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved. Read more |
 |
| Dental Dictionary. Mosby's Dental Dictionary. Copyright © 2004 by Elsevier, Inc. All rights reserved. Read more |
 |
| Medical Dictionary. The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Read more |
 |
| Wikipedia. This article is licensed under the Creative Commons Attribution/Share-Alike License. It uses material from the Wikipedia article "Hapten". Read more |
Mentioned in
