Abstract
Purpose :
Uveal choroidal melanocytes (UCM) are the most abundant cell type in the choroid. Beside photoprotection through melanin production, the functions of UCM are still not fully known. The aim of the study was to gain a better understanding of the role of UCM and their interaction with monocytes in vitro
Methods :
UCM were isolated and established from human donor eyes. Monocytes were purified from buffycoats from healthy blood donors. UCM and monocytes were monocultured as controls or co-cultured 1:1 in a direct manner for 45 hr at 5% CO2, 37°C, followed by collection of supernatant and cells. RNA was purified and subjected to human whole-transcriptome microarray (Human Gene 2.0 ST Array GeneChips, Affymetrix). Selected proteins were quantified from supernatant samples using ELISA.
Results :
We observed marked transcriptional responses when UCM and monocytes were co-cultured. Based on a 1.5-fold change criterion and a false discovery rate below 0.05%, 803 genes were upregulated and 329 genes were downregulated in UCM. In monocytes, 879 genes were upregulated and 468 genes were downregulated. Functional annotation analysis on upregulated genes in UCM after co-culture revealed functions relating to chemotaxis and antigen processing and presentation.
Gene expressions of different chemokines were upregulated in UCM after co-culture. Selected chemokines were quantified on protein level and increased levels were observed, consistent with the gene expression data.
Conclusions :
UCM appears to be immunologically active and able to attract leukocytes through chemokine secretion in response to monocyte stimuli. We have previously shown that UCM are able to inhibit T cell proliferation and might contribute to the immune privilege in the back of the eye.
Together, these data indicates that UCMs can be of significance in relation to inflammatory conditions affecting the posterior part of the eye.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.