Abstract:

Objective  To analyze the components of excretory-secretory protein（ESP） of Trichinella spiralis muscle larvae, and search for the anti-tumor protein components.  Methods  The Trichinella spiralis muscle larvae were collected, and ESP was prepared. The ESP was separated in 15% SDS-PAGE. Proteins extracted from the protein bands were lysed with trypsin, and analyzed by LC-MS/MS. The identified proteins were classified by Gene Ontology（GO） according to cell component, molecular function, and biological processes.  Results  SDS-PAGE revealed clear protein bands at Mr 10 000-142 000. A total of 162 proteins were analyzed with LC-MS/MS, of which 63 were identified, 34 were putative proteins, and 65 were unidentified proteins. Six anti-tumor relevant proteins were revealed, which were tropomyosin, histone H2A, cleavage and polyadenylation specificity factor subunit 2, serine proteinase inhibitor Kazal-type 4, Armadillo segment polarity protein and eukaryotic initiation factor 4A. The GO enrichment analysis showed that the identified proteins possessed 54 different types of molecular functions, and participated in cell structure and 382 biological processes.  Conclusion  The ESP of Trichinella spiralis muscle larvae has complex protein components, many with unknown identities. Six anti-tumor relevant proteins were determined from the 63 identified proteins.

Key words: Trichinella spiralis, Excretory-secretory protein, LC-MS/MS, Mass spectrometry