A Comparison of Emotionally Stimulated and Conventionally Collected Tears Using Bottom-Up, Label-Free Quantitative...

Area of Science:

• Biochemistry
• Proteomics
• Biomarker Discovery

Background:

• Tear proteomic analysis is key for identifying disease biomarkers.
• Tears are valuable for noninvasive biomarker discovery for ocular and systemic diseases.
• The proteome of psycho-emotionally stimulated tears is underexplored, limiting tear-based biosensor advancement.

Purpose of the Study:

• To compare the proteomic profiles of emotional and standard human tears.
• To understand the biochemical composition and functional roles of different tear types.
• To characterize psycho-emotional tears for biomarker discovery and biosensor development.

Main Methods:

• Proteomic profiling of human tears using a bottom-up approach.
• Comparison of tear samples from single donors elicited by emotional stimuli (n=6) and conventional techniques (n=14).
• Identification and functional characterization of significantly enriched proteins in emotional tears.

Main Results:

• A total of 907 proteins were identified across all tear samples.
• Fifty-two tear proteins were significantly enriched in emotionally stimulated tears.
• Enriched proteins are predominantly extracellular/secreted and involved in host defense and immune responses (e.g., S100A, neutrophil defensins).

Conclusions:

• Emotional tears possess distinct proteomic profiles compared to standard tears.
• Understanding these differences is vital for advancing tear-based biomarker discovery and biosensor technology.
• This study provides foundational characterization of psycho-emotional tears, highlighting their potential in diagnostics.