Comparative Human Salivary and Plasma Proteomes

Abstract

The protein compositions, or the proteomes, found in human salivary and plasma fluids are compared. From recent experimental work by many laboratories, a catalogue of 2290 proteins found in whole saliva has been compiled. This list of salivary proteins is compared with the 2698 proteins found in plasma. Approximately 27% of the whole-saliva proteins are found in plasma. However, despite this apparent low degree of overlap, the distribution found across Gene Ontological categories, such as molecular function, biological processes, and cellular components, shows significant similarities. Moreover, nearly 40% of the proteins that have been suggested to be candidate markers for diseases such as cancer, cardiovascular disease, and stroke can be found in whole saliva. These comparisons and correlations should encourage researchers to consider the use of saliva to discover new protein markers of disease and as a diagnostic non-proximal fluid to detect early signs of disease throughout the body.

Salivary proteins as biomarkers in dental caries: In vivo study

“…Presence of abundant proteins in human saliva such as amylases, proline rich proteins, statherin, histatin, mucin and cystatins create an opportunity to extensively study salivary proteome [14][15][16][17][18][19]. Modifications in this proteome composition indicate various physiological and pathological fluctuations [20].…”

Novel bioinformatic identification of differentially expressed tissue-specific and cancer-related proteins from the Human Protein Atlas for biomarker discovery

“…Due to the fact that the highly abundant proteins comprise 99% of the total protein mass in the blood (Loo et al, 2010), the discovery of poorly expressed cancer-specific proteins in the blood by routine biotechnology becomes difficult. It is hypothesized that potential protein biomarkers could be secreted or shed directly into the bloodstream, allowing the evaluation of their concentrations in cancer patients (Prassas et al, 2012), thus discovery and verification of circulating cancer biomarkers by indirect identification and subcellular localization analysis of tissue-specific proteins become effective alternative methods.…”

Saliva Biomarkers: The Unsung Hero of Diagnostics

“…Metabolites, electrolytes and other biomarkers are passively filtered into the saliva which are in harmony with the systemic and environmental conditions of an individual [1]. The potential of saliva as a biomarker fluid has been transformed by the development of highly sensitive proteomic analysis, which has identified over 2,000 proteins, approximately 25% to 30% of which are shared with blood (Table 1) [2]. Also, the ease of collection, easy storage, non-invasive sampling and possibility of repetition makes saliva an ideal fluid for the screening of diseases.…”