Microparticles And Ocular Inflammation: A Pilot Study

1. David Lockington¹
2. Elizabeth Macdonald¹
3. Mamun Rahman¹
4. Laurence Tetley²
5. Kanna Ramaesh¹

¹Tennent Institute of Ophthalmology, Glasgow, UK
²Glasgow Biomedical Research Centre, University of Glasgow, UK

Purpose
Microparticles have an increasingly recognised role in the mediation of inflammation. However, the ophthalmic implications have not been investigated. We wanted to assess if microparticles were present in tear samples of patients with active ocular surface inflammation.

Methods
Tear samples were assessed from 5 eyes with clinical ocular surface inflammation. There were also 4 control eyes without ocular surface inflammation. Sub-cellular structures were identified via scanning electron microscopy (SEM) to assess features and morphology. The structures were then evaluated for lipophilic properties with Nile red stain (a defining feature of microparticles).

Results
3 patients had corneal ulceration and 2 patients had conjunctivitis. SEM and Nile red staining identified sub-cellular structures consistent with microparticles. There was no positive identification of microparticles in the control group.

Conclusions
We have identified sub-cellular structures consistent with microparticles in the tear samples of patients with active ocular surface inflammation. They were not present in the non-inflamed ocular surface tear samples. Microparticles are components of ophthalmic inflammation. More research is needed to clarify their role in ocular surface disease.