Objective: To establish 2-dimensional polyacrylamide gel electrophoresis (2-DE) map from human nasal polyps and normal nasal mucosa, and to identify differential expression proteins of 2-DE map.
Methods: Samples of nasal polyps and nasal mucosa (each sample group containing 7 cases) were obtained. The total proteins were extracted and separated by immobilized pH gradient (IPG)-based 2-DE. The silver-stained 2-DE was scanned with digital Imagescanner and analyzed with ImageMaster 2-DE Elite 4.01 software. To obtain peptide mass fingerprint (PMF) of differential protein spots, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was used. The PMF was searched in Swiss-Prot and TreMBL database by Pept-Ident software, to identify differential expression proteins.
Results: The well-resolved, reproducible 2-DE maps of nasal polyps and nasal mucosa were established. For the polyps tissues, the average proteins spot of three 2-DE maps was 825+/-78; and 682+/-96 spot was matched with the average matching rate of 82.7%. The average deviations of matched spot position were (1.13+/-0.16) mm in IEF direction and (1.45+/-0.21) mm in SDS-PAGE direction, respectively. For the nasal mucosa tissues, the average proteins spot of three 2-DE maps was 936+/-62; and 821+/-78 spots were matched with the average matching rate of 87.7%. After comparing the 2-DE maps of nasal polyps and nasal mucosa tissues, the protein spots were 1,458 and 1,617 respectively; and 1,026 protein spots were matched. Forty differential expression protein spots were incised from silver staining gel randomly and digested in the gel by TPCK-Trypsin. Thirty-four PMFs were obtained by MALDI-TOF-MS and 24 differential proteins were identified.
Conclusion: The well-resolved, reproducible 2-DE maps of human nasal polyps and nasal mucosa have been successfully established. Certain differential proteins related to the pathogenesis of human nasal polyps are identified.