PSMA (prostate specific membrane antigen) is a 100-120kD type II, integral membrane glycoprotein,1 composed of a 19 amino acid intracellular domain containing the N-terminus, a 24 amino acid transmembrane region, and a 707 amino acid extracellular C-terminal domain. The PSMA gene has been cloned and sequenced, and has been localized to chromosome 11q. Three functionally distinct proteins are encoded, including folylpoly-gamma-glutamate carboxypeptidase in the intestine, N-acetylated alpha-linked acidic dipeptidase 1 in the brain, and prostate-specific membrane antigen in the prostate. PSMA is highly expressed in prostate secretory-acinar epithelium, in some benign extraprostatic epithelial cells from breast, duodenum, and kidney tissues, and in prostate cancer. On the basis of its highly prostate-specific nature, PSMA has been used as a prostate cancer marker antigen and diagnostic target for prostate cancer detection. Recently, evidence of limited and specific endothelial PSMA expression has been discovered: the neovasculature of a wide variety of malignant neoplasms (lung, colon, breast, etc.) demonstrates PSMA expression. This finding suggests that PSMA may be an effective target for monoclonal antibody-based anti-neovasculature therapy. PSMA has also been identified in the human nervous system. Based on activity, immunoreactivity, and mRNA sequence comparison with one form of NAALADase, a neuropeptide that may modulate glutaminergic transmission in the nervous system, PSMA was found to be indistinguishable from NAALADase derived from human cerebellar cell isolates. Therefore, the form of NAALADase also known as PSMA is expressed in brain, where it makes up a significant fraction of brain NAALADase activity.
Suitable for use in ELISA and Western Blot. Other applications not tested.
Western Blot: 1:200-1:300
Optimal dilutions to be determined by the researcher.
Mouse FO myeloma cells with spleen cells from BALB/c mice immunized with a recombinant human PSMA protein.
Storage and Stability:
May be stored at 4 degrees C for short-term only. For long-term storage and to avoid repeated freezing and thawing, aliquot and store at -20 degrees C. Aliquots are stable for at least 12 months at -20 degrees C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.