Western blot analysis of serum and urine samples. These are shown for a patient with strong (NW29), weak (NW1241), and negative (NW886) NY-ESO-1 serum antibody reactivity. Blots with 1 µg/lane recombinant NY-ESO-1 `short´ protein (14 kDa) were probed with serum (s; 1:1,000 dilution), urine (u; 1:100 dilution) and the E978 mouse monoclonal antibody as positive control (1:250 dilution). As negative controls, no serum (0) and serum obtained from a healthy donor (HD) were used at a 1:250 dilution.