1. Tears: a future vision for the biomarker discovery in medicine?
Marianne Dor1, Jonathan Sidibe2, Aurélien Thomas2,3, Natacha Turck1
1OPTICS laboratory, Department of Human Protein Science, Faculty of Medicine, University of Geneva, Switzerland; 2Forensic Toxicology and Chemistry Unit, CURML; CHUV, Lausanne, Switzerland; Department of Ophthalmology, 3Faculty of Biology and Medicine, Lausanne University Hospital, University of Lausanne, Lausanne, Switzerland
COMPLEX MOLECULAR COMPOSITION
BIOMARKER CANDIDATES
Multiple sclerosis, a central nervous system disease.
Thyroid-associated orbitopathy (TAO), an autoimmune inflammatory disease.
Allows the adherence of the tear film against the cornea
Carry nutriments and control infectious agents
Hydrophobic, limiting tear evaporation
Proteins
2115 proteins identified
Metabolites
195 metabolites identified
Alpha-1-antichymotrypsin, a protein of the acute phase inflammation.
Retinal dehydrogenase, related to visual pigment health.
Kishazi, E., et al., Thyroid-associated orbitopathy and tears: A proteomics study. J Proteomics, : p
Salvisberg, C., et al., Exploring the human tear fluid: discovery of new biomarkers in multiple sclerosis. Proteomics Clin Appl, (3-4): p
Dry Eye Disease, one of the most common eye impairments.
Virus and parasites
Lipids
Tear lipid profile. OAHFA: (O-acyl)-ω-hydroxy fatty acid, WE: wax ester, TAG: triacylglycerol, PL: phospholipids, CE: cholesterol ester.
S100A6 and MMP9, two proteins involved in inflammatory processes.
Brown, S.H., et al., A comparison of patient matched meibum and tear lipidomes. Invest Ophthalmol Vis Sci, (12): p
Soria, J., et al., Tear proteome analysis in ocular surface diseases using label-free LC-MS/MS and multiplexed-microarray biomarker validation. Sci Rep, (1): p
CURRENT STATE AND PROMISES FOR THE FUTURE
CHALLENGING ISSUES STILL ONGOING
Dry Eye Disease
Inflammadry®, a point-of-care test developed by RPS Diagnostics (Florida, US).
TearLab Osmolarity System, from TearLab™ (California, US).
Easy to collect
Invasiveness
Painless
Timeless (5 min)
No risk
Advantages:
Rapid, easy
Cost effective
Multi-testing
Self-testing?
Provide accurate measurements
A step further in personalised medicine
How to manage individual variabilities?
How does our environment influence our tear composition?
How to deal with the variability in term of collected volume?
What are the limitations of using tears in clinics?
Do we need to adapt the current clinical and diagnostic technics for tears?
Less than 300 research articles about tears and biomarkers in the last decade  everything remains to be done
Glaucoma
Contact lense that detects eye pressure changes.
Contact lens to mesure glucose level of diabetic patients, an ongoing project from Google and Novartis.
Future: diabete?
Tear based breast cancer screening, from Ascendant Dx™ (Arkansas, US).
Cancer
This work was supported by Swiss National Science Foundation Grants to N. Turck (#PMPDP3_158370), A. Thomas (# ), and the Provisu Foundation.