Identification of immunogenic antigens using a phage-displayed cDNA library from an invasive ductal breast carcinoma tumour.

The identification of immunogenic antigens for serological testing and vaccine development is a major challenge facing cancer immunology research. To study the humoral immune response in patients with breast cancer, a T7 phage display cDNA library from an invasive ductal breast carcinoma was panned on patient serum IgG antibodies. By monitoring the selection with an immunoscreening technique, positive phage-displayed cDNA products reacting with breast cancer patient IgG antibodies were selected. Sequence analysis identified immunogenic antigens such as the cytochrome oxidase I, sp100 and Ran GTPase activating protein. Additionally, immunogenic uncharacterized gene products were also identified. Both the known and unknown immunoselected gene products should offer an additional source for cancer gene discovery for diagnostic testing and vaccine development.