Background & objective: Screening tumor antigens plays a key role in early diagnosis of ovarian carcinoma. Several technologies, such as phage antibody library, ribosome display, and serological analysis of recombinant cDNA expression libraries (SEREX), have been applied widely. This study was to screen and identify tumor antigens of ovarian carcinoma by Western blot, immunoprecipitation, and mass spectrometry, and to establish a new methodological entity.
Methods: Western blot was used to find out the obviously different serum in ovarian carcinoma patients; SKOV3 cells lysate was added in the serum; immunoprecipitation was used to enrich antigens; then, the different protein band was gained when compared with normal serum immunoprecipitates, identified by mass spectrometry, and analyzed with bioinformatics.
Results: The serum of patient No. 7 was the obviously different one screened with Western blot. Immunoprecipitation and SDS-PAGE showed a different protein band in the serum appeared in the position of about 66.2 ku when compared with normal serum immunoprecipitates. Through mass spectrometry and bioinformatics analysis, heat shock protein 70 (HSP70) and cytokeratin 9 were identified in the different protein band.
Conclusion: Western blot, immunoprecipitation, and mass spectrometry is an effectively methodological entity for screening and identifying tumor antigens.