iTRAQ-based proteomics profiling of Schwann cells before and after peripheral nerve injury.

Objective(s): Schwann cells (SCs) have a wide range of applications as seed cells in the treatment of nerve injury during transplantation. However, there has been no report yet on kinds of proteomics changes that occur in Schwann cells before and after peripheral nerve injury. Materials and Methods: Activated Schwann cells (ASCs) and normal Schwann cells (NSCs) were obtained from adult Wistar rat sciatic nerves. After immunofluorescence identification, we identified differentially expressed proteins in the ASCs and NSCs using isobaric tags for relative and absolute quantitation (iTRAQ) combined with high-resolution Orbitrap liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). In addition, all the differentially expressed proteins were analyzed by Gene ontology (GO) analysis and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis. Finally, several differentially expressed proteins were selected for Western blot verification. Results: A total of 122 differentially expressed proteins in ASCs and NSCs were screened. GO analysis suggested that these different proteins are likely to accumulate in the cytoplasm and are associated with single-multicellular organism processes. The KEGG pathway analysis suggested that proteins related to purine metabolism were significantly enriched. The expression of Transmembrane glycoprotein NMB (GPNMB), Ectonucleotide pyrophosphatase/phosphodiesterase family member 3 (ENPP3), and other proteins were consistent with the proteomics data obtained by Western blot analysis. Conclusion: GPNMB, ENPP3, GFPT2, and other proteins may play an important role in the repair of peripheral nerve injury. This study may provide new insights into changes in SCs after peripheral nerve injury.