Comparative proteomic analysis of human oral fluids according to gender and age

Background: Recently, interest in finding disease bio-markers in human body fluids including oral fluids (OF), mainly saliva has increased. However, the physiologic differences in salivary proteins according to gender and age should be explored to establish a clinical diagnostic tool.Objective: To compare OF protein expression according to gender and age, using proteomic approaches.Materials and Methods: Oral fluids from 27 healthy volunteers (14 males, 13 females) was collected and divided into three age-groups. OF proteins were separated by means of 2D-SDS-PAGE. A total of 51 proteins in 37 protein spots were identified by ESI-MS/MS.Results: Gender differences revealed six proteins with significant higher expression in females, including β-2-microglobulin and transferrin. Age differences revealed decrease in expression of eight proteins with aging among males and seven proteins differentially expressed with aging among females including prolactin inducible protein, Ig-k light chain, transferrin, and calgranulin-B.Conclusion: Proteomic analysis of OF revealed differences in protein expression according to gender and age and therefore can highlight future use of this technique for diagnostic purposes in health and in disease.