MESOMARK™: A Potential Test for Malignant Pleural Mesothelioma

Clinical Chemistry. 2007 Apr;53(4):666-72. Epub 2007 Feb 8. [Link]

Heather L. Beyer, Ryan D. Geschwindt, Curtis L. Glover, Ly Tran, Ingegerd Hellstrom, Karl-Erik Hellstrom, M. Craig Miller, Thorsten Verch, W. Jeffrey Allarda, Harvey I. Pass and Niranjan Y. Sardesai

1 Research and Development Division, Fujirebio Diagnostics, Inc., Malvern, PA.

aAddress correspondence to this author at: Research and Development Division, Fujirebio Diagnostics, Inc., 201 Great Valley Pkwy., Malvern, PA 19355. Fax 610-240-3803; e-mail allardj@fdi.com.

Abstract

Background: Soluble mesothelin-related peptides (SMRP)have been reported to be potential biomarkers for malignant pleural mesothelioma (MPM). We report analytical and preliminary clinical studies of MESOMARKTM, a quantitative assay for SMRP.

Methods: The MESOMARK assay is a 2-step immunoenzymatic assay in an ELISA format with a 6-point calibration curve (0–32 nmol/L). We assessed analytical imprecision, analyte stability, and analytical interferences. We measured SMRP by this assay in 409 apparently healthy individuals (reference interval study), 177 patients with nonmalignant conditions, and 500 cancer patients, including 88 with MPM.

Results: The limit of detection was 0.16 nmol/L. At 2–19 nmol/L, intraassay imprecision (CV) was 1.1%–5.3%, and total imprecision was 4.0%–11.0%. The mean dilution recovery for 5 samples was 109% (range, 99%–113%). No interference was seen from added bilirubin (200 mg/L), hemoglobin (500 mg/L), triglycerides (30 g/L), chemotherapeutic agents, or other tested substances. Recombinant mesothelin was stable in serum upon freeze/thaw at –70 °C and upon storage for at least 7 days at 2–8 °C. The 99th percentile of the reference group was 1.5 nmol/L [95% confidence interval (CI), 1.2–1.6 nmol/L; n = 409], and mean SMRP was significantly higher in sera from patients with MPM (7.5 nmol/L; 95% CI, 2.8–12.1 nmol/L; n = 88). SMRP was increased in 52% and 5% of MPM patients and asbestos-exposed individuals, respectively. Concentrations in other nonmalignant and malignant conditions were similar to those in healthy controls.

Conclusions: The MESOMARK assay is analytically robust and may be useful for the detection and management of mesothelioma.