Performance characteristics of IMMULITE TPS: a comparison with TPS IRMA

This paper describes an automated immunoassay for the measurement of TPS developed for the IMMULITE. The IMMULITE system is a fully automated continous random access analyzer, which uses enzyme-amplified chemiluminiscent as the detection system. The IMMULITE TPS assay is a sequential, two-site chemiluminiscent enzyme immunometric assay designed for the quantitative measurement of TPS in serum. The IMMULITE TPS assay covers a clinical concentration range of 20-2400 U/L, with a lower detection limit of 6 U/L. A serum method comparison (n = 340) to the TPS IRMA assay demonstrates a correlation coefficient of 0.961 and a slope of 1.04. Samples run on IMMULITE TPS assay exhibit linearity upon dilution where recovered values fall within 15% of the theoretical sample value. The intra-assay precision of the IMMULITE TPS assay ranged from 3.3-4.7%, while the interassay precision ranged from 3.9-6.0%. By using different methods (immunoradiometric assay vs chemiluminiscent enzyme-labeled immunometric assay, one-step procedure vs sequential two-step procedure, manual vs fully automated procedure) the two TPS tumor marker tests used in this study gave quite comparable determinations for the sera from the cancer patients.