Serum-based ALYGNSA immunoassay for the prostate cancer biomarker, total prostate-specific antigen (tPSA)

• DOI: 10.1007/s00216-010-3827-0
• Publication Date: 2010-06-16T17:03:28Z
• Authors: Brian C. Mackness; Melisenda J. McDo...
• Keywords: Immunoassay; Male; 03 medical and health sciences; 0302 clinical medicine; Limit of Detection; Humans; Prostatic Neoplasms; Prostate-Specific Antigen; Biomarkers; 3. Good health

Prostate-specific antigen (PSA) is a serum glycoprotein overproduced by the prostate in prostate cancer (> or = 4 ng/mL in the bloodstream). An immunoassay for total PSA (tPSA) was developed using the ALYGNSA method to enhance capture antibody orientation and a limit of detection of 0.63 ng/mL was reported, a limit 15-fold lower than a commercial tPSA ELISA assay. This ALYGNSA assay, however, was performed using only buffer-based proteins and blocking agents (Mackness et al., Anal Bioanal Chem 396:681-686, 2010). To improve the clinical application of this system, a serum-based tPSA ALYGNSA was developed employing human serum. This assay also resulted in a limit of detection of 0.63 ng/mL of tPSA protein. The findings reported here provide support for the clinical application of this assay for diagnosis, progression, treatment, and possible recurrence of prostate cancer.