An abzyme (from antibody and enzyme), also called "catmab" (from "catalytic monoclonal antibody"), is a monoclonal antibody with catalytic activity. Molecules which are modified to gain new catalytic activity are called synzymes. Abzymes are usually artificial constructs, but are also found in normal humans (anti-vasoactive intestinal peptide autoantibodies) and in patients with autoimmune diseases such as systemic lupus erythematosus, where they can bind to and hydrolyze DNA. Abzymes are potential tools in biotechnology, e.g., to perform specific actions on DNA.
Enzymes function by lowering the activation energy of the transition state, thereby catalyzing the formation of an otherwise less-favorable molecular intermediate between reactants and products. If an antibody is developed to a stable molecule that's similar to an unstable intermediate of another (potentially unrelated) reaction, the developed antibody will enzymatically bind to and stabilize the intermediate state, thus catalyzing the reaction. A new and unique type of enzymes are produced.
HIV treatment
In a June 2008 issue of the journal Autoimmunity Reviews,[cite web |url=http://www.physorg.com/news135360794.html |title=UT pathologists believe they have pinpointed Achilles heel of HIV |format= |work=physorg.com |accessdate=2008-07-16] researchers S Planque, Sudhir Paul, Ph.D, and Yasuhiro Nishiyama, Ph.D of the University Of Texas Medical School at Houston announced that they have engineered an abzyme that degrade the superantigenic region of the gp120 CD4 binding site. This is the one part of the HIV virus outer coating that does not change, because it is the attachment point to T lymphocytes, the key cell in cell-mediated immunity. Once compromised, patients produce antibodies to the more changeable parts of the viral coat. The antibodies are ineffective given the virus' ability to change that coat rapidly. Because this protein, gp120, is necessary for the HIV virus to attach, it does not change, and is vulnerable across the entire range of the HIV variant population. ]The abzyme does more than bind to the site, rendering the HIV virus inert, it actually destroys the site, then can attach to other viruses. A single abzyme can destroy thousands of HIV viruses. Human clinical trials will be the next step in producing treatment and perhaps even preventative vaccines and microbicides.
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