ABSTRACT
<p><b>OBJECTIVE</b>To identify cancer-derived immunoglobulin G (IgG) whole molecule-interacting proteins to provide important clues for studying IgG biological functions.</p><p><b>METHOS</b>HeLa cell lysate was immunoprecipitated with rabbit antihuman IgG whole molecule antibody and normal rabbit IgG. The immunocomplex underwent sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and was detected with silver staining. Three prominently enhanced bands were subjected to protein identification with liquid chromatography-tandem mass spectrometry (LC-MS/MS), and the MS data were analyzed with Swiss-Prot database. Cancer-derived IgG whole molecule-interacting proteins were screened and functionally annotated.</p><p><b>RESULTS AND CONCLUSION</b>We identified 6 potential cancer-derived IgG whole molecule-interacting proteins with co-immunoprecipitation combined with LC-MS/MS, which provides valuable clues for studying the function of cancer-derived IgG.</p>