Abstract
Purpose :
To confirm, in a larger population, results from a study of conjunctival epithelial cells gene expression associated to contact lens (CL) wear (CLW) and discomfort (CLD).
Methods :
Thirty-six subjects were recruited in this new study in order to complete the data from the 24 ones enrolled in a previous study done by our group (López-de la Rosa et al., Ocul Immunol Inflamm, 2019). Therefore, a total of 60 subjects were included in this analysis: 40 CLWs, further divided into 20 asymptomatic CLW (ACLW) and 20 symptomatic CLW (SCLW) according to the CLDEQ-short form, and 20 non-CLWs. The exclusion criteria were extended or continuous CL wear (overnight use) and the presence of dry eye disease. CL wearers had to be CL users for at least 6 months before being included in the study. Conjunctival impression cytology was used to collect bulbar conjunctival epithelial cells. Expression of 84 genes related to neuropathic and inflammatory pain was analysed by RT-PCR using a commercial PCR array. The effect of CL wear and discomfort between non-CL and CL-wearers and between ACLW and SCLW was analysed. Additionally, a gene set enrichment analysis was performed in order to assign biological meaning to the genes differentially expressed.
Results :
6 genes were found to be significantly upregulated in the CL wearers compared to the non-wearers: CD200, EDN1, PTGS1 and TNF, involved in modulation of pain responses, P2RX7 related to pain conduction, and GRIN1, involved in synaptic transmission. Regarding CLD, 11 genes were found to be significantly downregulated in SCLW subjects compared to ASCLW: BDKRB1, DBH, PDYN, PTGS1 and TNF, related to pain responses modulation, CACNA1B, GRIN1, GRM1 and HTR1A, related to synaptic transmission, and ADORA1 and P2RX3, involved in pain conduction.
Conclusions :
The present study confirms previous findings of the increased expression of CACNA1NB and PTGS1 genes in conjunctival epithelium associated with CLW, and also includes the finding of EDN1, P2RX7 and TNF upregulated genes. Additionally, this study also confirms the previously reported alteration in ADORA1, BDKRB1, CACNA1B, HTR1A, PTGS1, and PYDYN genes associated with CLD. Additionally, DBH, GRIN1, GRM1 and TNF genes have been also found to be significantly altered in CLD. CL wear and CLD might be responsible for, or related to, changes in several pain-related gene expression in conjunctival epithelial cells.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.