Isolation and characterization of a possible new protein marker for differential diagnosis between metastatic carcinoma and mesothelioma cells in serous effusions: preliminary findings.

A distinctive diagnostic staining pattern of the cytoplasm of reactive and neoplastic mesothelial cells in serous effusions was assumed to be caused by a specific compound. This was isolated by polyacrylamide gel electrophoresis and corresponded to a protein with an apparent molecular weight around 200,000. Isoelectric point was found to be 8.7. This protein contained high proportions of glutamic acid, serine, and glycine.