abia PSA total
abia PSA total is an enzyme immunoassay for the quantitative determination of total prostate specific antigen (tPSA) concentration in human serum or plasma.
For professional use only.
Clinical value
Human prostate specific antigen (PSA) is a serine protease, a single chain glycoprotein with a molecular weight of approximately 33 kDa containing 7% carbohydrate by weight.
PSA is immunologically specific for prostatic tissue. It is present in normal, benign hyperplastic, and malignant prostatic tissue, in metastatic prostatic carcinoma, and also in prostatic fluid and seminal plasma. PSA is not present in any other normal tissue obtained from men, nor is it produced by cancers of the breast, lung, colon, rectum, stomach, pancreas or thyroid. Besides, it is functionally and immunologically different from prostatic acid phosphatase (PAP). Elevated serum PSA concentrations have been reported in patients with prostate cancer, benign prostatic hypertrophy, or inflammatory conditions of other adjacent genitourinary tissues, but not in men with non-prostatic carcinoma, apparently healthy women, or women with cancer. Reports have suggested that serum PSA is one of the most useful tumor markers in oncology. It may serves as an accurate marker for assessing response to treatment in patients with prostatic cancer.
Therefore, measurement of serum PSA concentrations can be an important tool in monitoring patients with prostatic cancer and in determining the potential and actual effectiveness of surgery or other therapies.
Principle of the test
abia PSA total is an one-step immunoassay, based on the principle of the “sandwich” method.
The assay system utilizes high affinity and specificity monoclonal antibodies (enzyme conjugated and immobilized) directed against a distinct antigenic determinant on the intact tPSA molecule.
The test sample is allowed to react simultaneously with the two antibodies, resulting in the tPSA molecules being sandwiched between the solid phase and enzyme-linked antibodies.
The unbound components are removed by washing. After addition of the solution containing TMB and hydrogen peroxide, the wells with bound conjugate develop a blue color which is converted to yellow after the reaction has been stopped with sulphuric acid.
The color intensity is directly proportional to the concentration of tPSA in the specimen and can be read at 450 nm.