Abstract
Purpose :
To investigate and compare expression of MUC16 in temporal and superior bulbar conjunctiva as well as the upper palpebral conjunctiva on the ocular surface in both normal and dry eye subjects.
Methods :
Fourteen subjects were recruited as normal (n = 7) and dry eye with previous diagnosis and corneal staining (n = 7). Slit lamp examination and ocular surface testing were performed. Impression cytology was performed on the temporal and superior bulbar conjunctiva and the upper palpebral conjunctiva by applying a 7.5 mm semicircle of filter paper (0.45µm pore size). Right and left eye samples from each subject were stored together by sampling location. Gene expression was measured using the Taqman Cells to CT Kit and evaluated by real-time PCR using Taqman probes. Expression levels were normalized using housekeeping gene GAPDH followed by non-parametric statistical analysis using the Kruskal-Wallis test.
Results :
MUC16 expression was detected in the palpebral conjunctiva of the upper eyelid in both normal and dry eye subjects. The median ΔCT values in normal subjects were 3.4 (IQR 2.8-4.9), 4.6 (IQR 3.8-5.9), and 5.1 (IQR 3.5-6.3) for the temporal bulbar, superior bulbar, and palpebral conjunctiva respectively. For dry eye subjects, median ΔCT values were 3.6 (IQR 1.7-4.4), 3.8 (IQR 3.5-4.9), and 5.0 (IQR 4.7-5.9) for the temporal bulbar, superior bulbar, and palpebral conjunctiva respectively. There was not a statistically significant difference in regional expression of MUC16 in the normal samples (H = 2.3, p = 0.34). While the overall statistical test for the dry eye samples (H = 6.0, p = 0.04) was significant, only the comparison between the temporal bulbar and upper lid expression approached significance (p = 0.06).
Conclusions :
The results demonstrate expression of MUC16 in the palpebral conjunctiva. The palpebral conjunctiva in both normal and dry eye subjects showed the highest level of MUC16 expression followed by the superior bulbar conjunctiva and temporal bulbar conjunctiva.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.