A set of proteins found in saliva may one day lead to ‘spit’ tests replacing blood tests for cancer, heart disease or diabetes.
A major step in that direction is the cataloguing of the ‘complete’ salivary proteome, a set of proteins in human ductal saliva, identified by a consortium of three research teams, according to an article in the Journal of Proteome Research.
Replacing blood tests with saliva tests – the term saliva increasingly reserved for just the salivary gland secretions – promises to make disease diagnosis, as well as the tracking of treatment efficacy, less invasive and less costly.
Saliva proteomics and diagnostics is part of a nationwide effort to create the first map of every human protein and every protein interaction, as they contribute to health and disease and as they act as markers for disease states.
Defining exact protein pathways on a comprehensive scale enables the development of early diagnostic testing and precise drug design.
Recently, US scientists were reported to be developing a test to allow dentists to check patients’ saliva for signs of breast cancer.
Experts in Houston identified the proteins that can diagnose the disease and reasoned that the saliva can be examined for these marker proteins.
In the current study, researchers sought to determine the ‘complete’ set of proteins secreted by the major salivary glands (parotid, submandibular (SM) and sublingual (SL)).
Recent, parallel efforts that mapped the blood (plasma) and tear proteomes allows for useful comparisons of how proteins and potential disease markers are common or unique to different body fluids.
‘Past studies established that salivary proteins heal the mouth, amplify the voice, develop the taste buds and kill bacteria and viruses,’ said James E Melvin, director of the Center for Oral Biology at the University of Rochester Medical Center, and an author on the paper.
‘Our work, and the work of our partners, has shown that salivary proteins may represent new tools for tracking disease throughout the body – tools that are potentially easier to monitor in saliva than in blood.’
‘We believe these projects will dramatically accelerate diagnosis and improve prognosis by treating diseases at the earliest stages,’ said Mireya González Begné, research assistant professor of Dentistry in the Center for Oral Biology at the Medical Center.
‘Researchers have already shown that saliva proteins can be used to detect oral cancer and HIV infection. We think this list will soon expand to include leading causes of death like cancer and heart disease, which, if caught early, are much more likely to be successfully treated.’