Figure 1.

The immunosecretomics workflow. Secretomes are prepared from five human colorectal carcinoma cell lines. A 2-dimensional secretome master map is established. Corresponding 2-dimensional Western blots are prepared using individual sera from CRC patients and healthy controls to indicate autoantigens. Signals derived from autoantibodies in the sera are matched to the master map, corresponding proteins are excised from preparative gels and identified by mass spectrometry and database searches. Ultimately, the autoantigen candidates are confirmed by duplex Western blotting with human sera and with specific antibodies directed against the protein of interest.