Impression cytology implicates cell autophagy in aqueous deficiency dry eye

Abstract

Tony Lin,1,2,* Richard Filek,3,* Joy M Wang,4 Chong H Wu,4 Hong Liu,2 Cindy ML Hutnik1–3 1Department of Ophthalmology, Western University, 2Ivey Eye Institute, St Joseph’s Health Care, St Joseph’s Hospital, 3Department of Pathology and Laboratory Medicine, 4Department of Biology, Western University, London, ON, Canada *These authors contributed equally to this work Purpose: Impression cytology in combination with a cell autophagy marker was used to demonstrate the utility of a novel frozen section technique, to assess the health of the ocular surface, as well as to correlate autophagic cell death with the commonly used clinical tests for dry eye. Methods: Female patients over the age of 18 years who attended an outpatient ophthalmology clinic were invited to participate. Schirmer’s test, tear film break-up time and the ocular surface disease index questionnaire were used as objective and subjective clinical tests for dry eye. The cellular biomarker microtubule-associated protein light chain 3 (LC3) was used as a marker of autophagic cell death. Results: Low LC3 nuclear staining was positively correlated with Schirmer’s test <10 mm. No correlation was found between other clinical tests for dry eye. Conclusion: This study demonstrates a positive linear relationship between Schirmer’s testing and LC3. There is a lack of correlation between the commonly used diagnostics tests for dry eye, highlighting our incomplete understanding and assessment of dry eye. Keywords: impression cytology, cell autophagy, dry eye, technique, Schirmer’s test, LC3

Keywords

• impression cytology
• cell autophagy
• dry eye
• technique
• schirmer test
• LC3