Abstract
Purpose :
Ocular discomfort is the primary reason for discontinuation from contact lenses. This discomfort may be mediated by ocular surface inflammation, although its precise molecular basis remains unclear. We have developed a novel mass cytometry panel capable of determining surface markers (enabling cell identification) and levels of intracellular cytokines in cells removed from the ocular surface by impression cytology. We sought to identify the biomarkers associated with contact lens discomfort in a group of symptomatic soft contact lens wearers.
Methods :
Ten asymptomatic (CLDEQ-8 score ≤10) and 10 symptomatic (CLDEQ-8 score ≥20) soft contact lens wearers were recruited. Impression cytology samples were taken from the bulbar conjunctiva and central upper eyelid margin using an Eyeprim device (OPIA Technologies, France). Cells were removed from the Eyeprim membrane and stained with a mass cytometry panel targeting 30 cell surface markers or intracellular proteins. This panel allowed the identification of a range of immune cells, epithelial cells, inflammatory proteins and extracellular matrix remodelling proteins. Samples were analysed using mass cytometry and Cytofkit was used to assess protein expression levels.
Results :
We observed a x2.2 increase in matrix metalloproteinase-9 (MMP-9), x1.1 increase in macrophage- derived chemokine (MDC) and x2.0 increase in interleukin-23 (IL-23) in the eyelid margin epithelial cells of symptomatic compared to asymptomatic lens wearers. A x1.4 increase in MMP-9 was also observed in the conjunctival epithelial cells of symptomatic compared with the asymptomatic wearers. Furthermore, a decrease in the anti-inflammatory cytokine IL-10 was observed in eyelid margin epithelial cells of symptomatic compared with asymptomatic subjects.
Conclusions :
Increased levels of MMP-9, MDC, IL-23 and decreased levels of IL-10 were observed in the eyelid margin and conjunctiva of symptomatic compared with lens asymptomatic soft lens wearers. These have potential as biomarkers for contact lens discomfort, and indeed some of these mediators have previously been implicated in the inflammatory events underlying dry eye disease. This methodology enables measurement of precise levels of inflammatory markers inside specific cell types, making it ideal for the investigation of the ocular surface.
This is a 2021 ARVO Annual Meeting abstract.