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From
Wikipedia, the free encyclopedia
Human anti-mouse antibody (HAMA) is an antibody found in humans which reacts
in immunoglobins found in mice.[1]
The HAMA Response
Antibody treatment is a type of therapy that is used to treat certain types
of cancer and immune disorders. Antibodies are proteins which are naturally
formed by the body in response to a foreign substance, known as an antigen.
Antibodies can also be grown outside of the patient’s body and injected into
them to help aide the immune system to fight disease. These types of
antibodies are typically called monoclonal antibodies because they are
created to target one specific antigen.[2] Herceptin and Avastin, two widely
used cancer fighting drugs, are examples of monoclonal antibodies.
For several decades, and until recently, mice were used extensively in the
production of monoclonal antibodies (MAbs). But the treatments were not as
effective as doctors had hoped. One problem was that patients reacted to the
mouse antibodies as if they were a foreign substance, and created a new set
of antibodies to the mouse antibodies. Doctors have termed this the “HAMA
response,” referring to the development of Human Anti-Mouse Antibodies (HAMA).
The HAMA response is essentially an allergic reaction to the mouse
antibodies that can range from a mild form, like a rash, to a more extreme
and life-threatening response, such as renal failure. HAMA can also decrease
the effectiveness of the treatment, or create a future reaction if the
patient is given a subsequent treatment containing mouse antibodies. [3]
It has been observed that anywhere from one-third to more than half of
patients receiving mouse-derived antibodies will develop some form of HAMA
response. [4] [5] Even more startling, at least ten percent of the general
population has been observed to carry some form of animal-derived
antibodies, most often from mice, due to the preponderance of medical agents
made from the serum of animals. [6]
Monoclonal antibodies can be generated for human use without mice by using
in vitro techniques. MAbs manufactured using these methods do not suffer
from the drawbacks related to the HAMA response.Animal protection groups
fought for years to end MAb production in mice because it causes intense
suffering for the animals that includes severe abdominal pain, difficulty
breathing and death. [7] [8]
It took considerable, sustained pressure from animal welfare groups, led by
legal efforts initiated by the American Anti-Vivisection Society, before
this would change. Today in vitro methods of MAb production are recognized
and promoted by the National Institutes of Health and are required of all
investigators who receive federal funding if their work involves producing
MAbs.
The existence of HAMA can complicate laboratory measurements.[ |
