Initial comparison of proteomic profiles of whole unstimulated saliva obtained from generalized aggressive periodontitis patients and healthy control subjects

BACKGROUND AND OBJECTIVE: Salivary proteomics technology can be used to evaluate the disease progression of periodontitis and the systemic screening of proteomes of saliva from subjects with aggressive periodontitis has not been available. The objective of this preliminary study was to compare the proteomic profile of whole unstimulated saliva of subjects with generalized aggressive periodontitis (GAgP) with that of healthy volunteers to identify proteins, the levels of which were significantly altered between the two groups. MATERIAL AND METHODS: Whole unstimulated saliva was obtained from five subjects with GAgP and five healthy subjects, and proteins were separated using two-dimensional gel electrophoresis. Proteins, the levels of which were significantly different between the two groups, were identified by computer image analyses and subsequent electrospray ionization tandem mass spectrometry. RESULTS: Eleven proteins that exhibited a different level in the GAgP group vs. the control group were identified. Compared with whole saliva of healthy control subjects, the levels of serum albumin, immunoglobulin (Ig) gamma2 chain C region, Ig alpha2 chain C region, vitamin D-binding protein, salivary alpha-amylase and zinc-alpha2 glycoprotein were increased in whole unstimulated saliva of GAgP subjects, while those of lactotransferrin, elongation factor 2, 14-3-3 sigma, short palate, lung and nasal epithelium carcinoma-associated protein 2 precursor and carbonic anhydrase 6 were decreased. CONCLUSION: Comparison of the proteomic profile of whole unstimulated saliva of GAgP subjects with that of healthy control subjects revealed at least 11 differential proteins. The approach applied herein might be helpful to aid understanding of the etiology of GAgP.