Abstract
Purpose :
To analyze the long term-evolution of gene expression changes in conjunctival epithelial cells in patients suffering from chronic ocular pain and dry eye (DE) after refractive surgery (RS).
Methods :
Patients with chronic ocular pain and DE after RS were included in this study. They attended two visits. In the first visit (V1) patients were evaluated, and a wide variety of personalized treatment for the management of pain and DE was prescribed. In the second visit (V2) (range: 3-7 years after V1), patients were prospectively evaluated to assess their evolution over time. On each visit, conjunctival epithelial cells were collected by conjunctival impression cytology. Expression of 25 genes (BDKRB1, BDNF, CALCA, CCL2, CD200, CNR2, CX3CR1, IL18, IL1A, IL2, IL6, ITGAM, NGF, NTRK1, OPRD1, OPRK1, OPRM1, PENK, PTGS1, TAC1, TACR1, TNF, TRPA1, TRPV1, and TRPV3) related to neuropathic and inflammatory pain was analysed in conjunctival epithelial cells by qPCR using a customized PCR array. GAPDH was used as housekeeping gene. Gene expression changes between visits were evaluated individually in each patient using paired t-test.
Results :
Twenty-two patients (63.6% females), with a mean age of 42.45±9.91 (range: 28-62) years, were included in the study. Out of the 25 genes analyzed, 15 (BDKRB1, BDNF, CALCA, CX3CR1, IL2, IL6, IL18, ITGAM, NGF, NTRK1, OPRK1, PTGS1, TNF, TRPV1, and TRPV3) were detected in more than 50% of the patients in both visits. IL6 expression was significantly upregulated at V2 compared to V1 (ΔCt= 11.11±3.285 vs 9.474±3.561; p=0.0212). IL18 and NGF were differentially expressed with borderline statistical significance, being both upregulated at V2.
Conclusions :
Changes in IL6, IL18 and NGF gene expression in conjunctival epithelial cells after long term treatment could be related to the evolution in the presence and/or intensity of ocular pain in these patients.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.