Single-tear proteomics for noninvasive biomarker discovery and precision medicine.
Ponzini E., Ami D., Borghesi A., De Palma A., Di Silvestre D., Duse A., Grandori R., Mauri P., Natalello A., Pezzoli F., Santambrogio C., Tavazzi S., Zeri F.
In the last decades, the lacrimal fluid has gained increasing interest as a potential source of biomarkers, thanks to its accessibility, moderate complexity, and responsiveness to physiopathological conditions. Despite the still limited number of studies, tear investigation, in particular single-tear analysis, could offer unique contributions to the identification of noninvasive and easily accessible biomarkers, and to the development of feasible approach to precision medicine. High-performance liquid chromatography-mass spectrometry (LC-MS) has led to promising approaches to tear proteomics, despite the intrinsic limitations in sample amounts that can be collected. By ultrahigh-resolution, shotgun proteomics, we developed and effective analytical pipeline for single-tear analysis and we analyzed the tear fluid of 23 healthy volunteers, achieving high-confidence identification of 890 proteins. This study demonstrates the feasibility of single-tear quantitative proteomics, highlighting the unique contributions that this unconventional body fluid can offer to personalized approaches in biomedicine.