Dept. of Orthodontics
Oregon Health & Science University
Introduction: Saliva is an easily accessible biofluid with diagnostic potential. Essential to saliva-based diagnostics is a complete catalog of proteins in saliva, as well as an understanding of the effect of collection method on its composition. For example, little is known of the changes to the whole human salivary proteome caused by stimulation. Purpose: The purpose of our study was to compare the proteome of stimulated vs. unstimulated whole human saliva. Methods and materials: Two samples of whole saliva, one unstimulated, one stimulated with citric acid, were collected from five healthy male subjects age 27-32. Saliva samples were analyzed using highly sensitive 2-dimensional-liquid chromatography/mass spectrometry (2D-LC/MS) to identify both major and minor proteins present. Relative protein amounts were estimated from the 2DLC/MS data utilizing spectral counting. Changes in protein relative abundance were compared using paired two-tailed Student's t-test. Results: The 2-DLC study was able to identify, with high confidence, 509 non-redundant proteins. 288 proteins found in at least 3 of 5 subjects were compared to detect changes in relative abundance. 36 proteins were found to change significantly (p<0.05) following stimulation (14 increased, 22 decreased). Conclusions: Stimulation with citric acid alters the proteome of human whole saliva, inducing changes in protein relative abundance. Future biomarker and proteome studies of whole saliva will need to account for the effect of stimulation on protein composition when considering collection protocols.
School of Dentistry
Carver, Chad D., "Comparison of protein composition in stimulated vs. unstimulated whole human saliva" (2007). Scholar Archive. 844.