Prostate Specific Antigen (PSA)

Prostate Specific Antigen (PSA) is a single-chain glycoprotein secreted by the epithelial cells of prostate follicles and ducts, and functionally belongs to the kinin-like peptide-releasing enzyme, a serine protease, which participates in the process of semen liquefaction and is routinely used in the diagnosis of benign and malignant diseases of prostate and the differential diagnosis of the important indexes.PSA in the human body The normal physiologic role of PSA in the human body is to help liquefy semen and is related to male reproductive function. As a specific marker for prostate cancer, it is also the only recognized organ-specific tumor marker. Elevated serum PSA generally indicates the presence of prostate pathology (prostatitis, benign hyperplasia or cancer). Serum PSA is one of the most important indicators for the detection and early detection of prostate cancer. The threshold value for positive serum TPSA quantification is greater than 10 μg/L, and the diagnostic specificity of prostate cancer reaches 90% to 97%.

KMD Bioscience is a high-tech biological enterprise engaged in the development and production of core raw materials for in vitro diagnostics. As a manufacturer of in vitro diagnostic reagents, KMD Bioscience provides antibodies, antigens, enzymes, nanomaterials and other raw materials for in vitro diagnostics. We have several mature technology platforms such as immunochromatography, latex turbidimetry, chemiluminescence and molecular diagnostics. Our main products are in vitro diagnostic antigens (natural antigens, genetically engineered recombinant antigens), antibodies (monoclonal antibodies, polyantibodies), fluorescent microspheres, etc., which cover a wide range of fields such as cardiovascular, renal, hormonal, diabetes, infectious diseases, autoimmune diseases and so on.

The inventory of reagents associated with Prostate Specific Antigen (PSA) that KMD Bioscience can offer:

Structural composition of PSA

Prostate specific antigen (PSA) is a protein that exists in both bound and free states in the blood. most of the PSA that enters the bloodstream quickly binds to protein hydrolase inhibitors to become complex PSA, or cPSA, while a small portion of the PSA that is inactivated by protein hydrolases exists in a free state, or fPSA. the sum of the two is called total PSA, or tPSA. PSA in the bloodstream is a combination of free PSA and complex PSA, or tPSA. In the blood, PSA is the sum of free PSA and complex PSA, also known as total PSA, denoted by tPSA. PSA is essentially a protease, and the main function of enzymes is to catalyze the hydrolysis of other substances. Under normal circumstances PSA is secreted by the epithelial cells of the prostate gland, directly into the prostate ductal system, and during sexual intercourse, it mixes with spermatozoa, seminal vesicle fluid, and other components to form the final semen. Although known as a prostate specific antigen, it has also been shown that very small amounts of PSA can also be detected in breast cysts, fetal amniotic fluid, and breast milk.

Biological functions of PSA

Normally a barrier exists between the ductal system of the prostate and the body's blood, similar to the blood-brain and placental barriers, and the main purpose of the barrier is to functionally delimit it. It is because of this barrier that very little of the PSA secreted by the prostate flows into the bloodstream, so that normal men can only monitor a very low value when their blood is drawn for PSA. If this barrier is breached, then the PSA secreted by the prostate is released into the bloodstream in large quantities. Diseases that can breach this barrier include prostate cancer, prostatitis, and bulky prostate enlargement, and operations that can stimulate the prostate, such as inserting a catheter or massaging the prostate, can also cause the PSA to rise temporarily. It is by utilizing this specificity of the PSA that the serum PSA test can be used for prostate cancer screening.

It is generally recognized that the combined measurement of TPSA and FPSA increases the detection rate of malignant prostate disease to over 90%. As a tumor marker, PSA determination has its irreplaceable superiority; however, there are many shortcomings, PSA only has prostate tissue specificity but not prostate cancer specificity; when prostate ischemia, hyperplasia, acute urinary retention, prostatitis, cystoscopy, rectal fingerprinting, or massage, serum PSA is significantly elevated. Therefore, PSA as an indicator for early diagnosis of prostate cancer still lacks sufficient sensitivity and specificity. In particular, there is considerable overlap between the serum PSA results of prostate cancer and benign prostatic hyperplasia, but it is generally recognized that PSA significantly improves the diagnosis of prostate cancer when combining serum PSA testing with clinical practice.

KMD Bioscience has an excellent in vitro diagnostic reagent development platform, all raw materials have been repeatedly validated through multiple application platforms and a large number of clinical samples, and under strict production process control, we can continuously and stably provide high-quality raw materials for our IVD customers. Most of our antigenic raw materials are prepared by mammalian expression system, the structure and activity are closer to natural antigen. Each antigen is produced through rigorous program design, strict performance evaluation, and has excellent stability and specificity. Moreover, our antigen materials can be used in the development of standards, calibrators, quality control products and as immunogens.