Dual-label one-step immunoassay for simultaneous measurement of free and total prostate-specific antigen concentrations and ratios in serum

Summary, in English

We developed a simple one-step dual-label immunoassay for simultaneous measurement of the free, noncomplexed form of prostate-specific antigen (PSA) and total PSA. The assay is based on time-resolved fluorescence and includes a stable fluorescent chelate of Eu to label a monoclonal antibody (mAb) that detects only free PSA, whereas a second mAb labeled with a fluorescent chelate of Tb provides equimolar detection of both free PSA and PSA complexed to alpha 1-antichymotrypsin. A third mAb on a solid phase captures the free and complexed forms of PSA in an equimolar fashion. The simultaneous measurement of the free-to-total PSA ratio (F/T) with the one-step dual assay is not sensitive to variations in the sample volume. The discrimination between benign prostatic hyperplasia and prostate cancer patients, i.e., the area under the receiver-operating characteristic curve, increased from 0.64 (total PSA assay) to 0.78 and 0.81 when the F/T ratio was measured with single and dual assays, respectively.

• Author: Katja Mitrunen; Kim Pettersson; Timo Piironen; Thomas Björk; Hans Lilja; Timo Lövgren
• Department/s: Urological cancer, Malmö; Clinical Chemistry, Malmö
• Publishing year: 1995
• Language: English
• Pages: 1115-1120
• Publication/Series: Clinical Chemistry
• Volume: 41
• Issue: 8
• Links: http://www.clinchem.org/cgi/reprint/41/8/1115
• Document type: Journal article
• Publisher: American Association for Clinical Chemistry
• Topic: Biochemistry and Molecular Biology
• Keywords: prostate cancer/benign prostatic hyperplasia/timeresolved fluorescence immunoassay/monoclonal antibodies
• Status: Published
• Research group: Urological cancer, Malmö; Clinical Chemistry, Malmö
• ISBN/ISSN/Other: ISSN: 0009-9147