iTRAQ labeling and SCX fractionation

Total protein (100 μg, determined by Bradford protein assay) was extracted from each sample solution, and the protein then digested with Trypsin Gold (Promega, Madison, WI, USA) at 37 °C for 16 h. After trypsin digestion, peptides were dried by vacuum centrifugation. Peptides were reconstituted in 0.5M TEAB and processed according to the manufacturer’s protocol for 8-plex iTRAQ reagent (isobaric tags for relative and absolute quantification). Briefly, one unit of iTRAQ reagent was thawed and reconstituted in 24 μL isopropanol. Samples were labeled with the iTRAQ tags as follow: oncosphere, adult and the protoscolex. The peptides were labeled with the isobaric tags, and incubated at room temperature for 2 h. The labeled peptide mixtures were then pooled and dried by vacuum centrifugation. SCX chromatography was performed with an LC-20AB HPLC Pump system (Shimadzu, Kyoto, Japan), according to the manufacturer’s instructions.