Adenosine deaminase (ADA) is an enzyme that is found in many cells throughout the body, including in white blood cells. Its primary function is to break down adenosine and deoxyadenosine, two molecules that are important in the production of DNA and RNA.
In medicine, measurement of ADA levels in the blood or other body fluids can be used as a diagnostic tool for various conditions. For example, low levels of ADA are associated with severe combined immunodeficiency (SCID), a rare genetic disorder that causes severe defects in the immune system. In SCID, low levels of ADA lead to a buildup of toxic metabolites that damage white blood cells and other tissues, causing a range of symptoms including recurrent infections and failure to thrive.
Elevated levels of ADA can also be indicative of certain medical conditions, including tuberculosis and certain types of cancer such as leukemia and lymphoma. Measurement of ADA levels in the fluid surrounding the lungs (pleural fluid) can also be used to diagnose conditions such as tuberculosis or lung cancer.
In addition to its diagnostic applications, ADA has also been used as a therapeutic agent in the treatment of certain diseases, including SCID. Enzyme replacement therapy, in which ADA is administered directly to the patient, can help to restore immune function and improve outcomes for patients with this condition.
In summary, adenosine deaminase (ADA) is an enzyme found in many cells throughout the body, with its primary function being the breakdown of adenosine and deoxyadenosine. Measurement of ADA levels in the blood or other body fluids can be used as a diagnostic tool for various medical conditions, including SCID, tuberculosis, and certain types of cancer. ADA has also been used as a therapeutic agent in the treatment of SCID and other conditions.