Abstract
Purpose :
Chronic blepharitis is an associated risk factor of obstructive MGD. New tools that can immunophenotype the ocular surface in a longitudinal fashion may help better understand the relationship between inflammation and MGD. Here, we leveraged large parameter flow cytometry to examine tear leukocyte content in various MGD patient populations.
Methods :
Patients were evaluated and consented at the Duke Eye Center. Severity of MGD was graded and tears were collected on a one-time basis. A total of n=64 subjects were included, which comprised of non-MGD controls (n=14) and MGD subjects (n=50). An n=12 MGD subjects had an underlying immune disease diagnosis (Sjögren’s, atopy, or rosacea), whereas others had MGD only (n=38). After tear collection, cells were resuspended and stained on a per subject basis for CD3, CD4, HLA-DR, CD11b, CD14, CD15, CD16, and viability dye.
Results :
Both lymphocytes (CD3+) and myeloid cells (CD3- CD11b+) were identifiable in MGD subject tears. Average leukocyte count in total MGD subject tears was significantly higher (p<0.001) relative to controls. Specifically, average count in immune disease subjects was statistically higher than control (p<0.001), and the same was observed in MGD only (p<0.001). Interestingly, average leukocyte count in immune disease subjects was statistically higher than in MGD only subjects (p<0.001).
Conclusions :
Tear leukocyte counts are amplified in MGD patients, which is consistent with the current understanding that obstructive MGD is associated with inflammation. In addition, we were also able to resolve a presence of increased tear leukocytes in subjects with underlying immune disease. Flow cytometry could be a useful tool in MGD research.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.