Method for detection of L523S expression in biological samples

A method of detecting L523S protein in a biological sample comprising normal or reactive and malignant cells, said method comprising:

• (a) obtaining a biological sample;
• (b) contacting the biological sample with an anti-L523S antibody, and detecting the binding between L523S protein and the antibody;
• (c) contacting the biological sample with an antibody to a second protein that is a marker of cell lineage, and detecting the binding of the antibody to the second protein;
• and
• (d) contacting the biological sample with an antibody to a third protein whose expression is restricted to normal or reactive cells, and detecting the binding of the antibody to the third protein;
• thereby producing cells having L523S protein bound to the anti-L523S antibody, the second protein bound to the antibody to the second protein, and the third protein bound to the antibody to the third protein;
• wherein the normal or reactive cells and malignant cells are mesothelial cells.