Abstract
Purpose :
Keratoconus (KC) is the most common ectatic corneal disease with the highest number of patients undergoing corneal transplantation. Despite recent advancements, KC pathobiology remains unclear. Our group, recently reported what we believe is the first-ever biomarker for KC. Prolactin-Induced Protein (PIP), is found to be significantly downregulated in human tears, saliva, blood (plasma), and corneal stromal cells. Our studies also indicated significant sex hormone imbalances in KC patients. We have now initiated in vitro studies in order to unravel downstream mechanisms and begin to cultivate novel, non-invasive therapeutic modalities.
Methods :
Human corneal stromal cells from healthy (HCF) and KC patients (HKC), were collected from the National Disease Research Interchange, the Aarhus University Hospital, and the Dean McGee Eye Institute. Both HCFs and HKCs were seeded at a density of 106 cell/well into polycarbonate transwell plates. Constructs were grown in 10% FBS EMEM media and stimulated with a stable Vitamin C derivative for 4 weeks. Cultures were treated with PIP (50ng/ml, 100ng/ml and 200ng/ml), and according to actual physiological levels, with DHEA-S (50µg/dl, 350µg/dl and 700µg/dl), Estrone (3pg/ml and 6pg/ml), and Estriol (1pg/ml, 3pg/ml and 7pg/ml) for the entire 4 week period. Cultures with no hormone stimulation served as controls. At the end of the 4 week time point, constructs were processed for further analysis.
Results :
Our data showed significant upregulation in estrogen receptor 1 and a downregulation of androgen receptor in HKCs, when compared to HCFs. Exogenous DHEA-S led to significant upregulation of fibrotic Collagen Type III and downregulation of cellular Fibronectin (cFN) in HKCs, while no significant modulation was noted in HCFs. Exogenous Estrone, on the other hand, led to significant downregulation of Collagen Type III in HCFs but not in HKCs. cFN was also downregulated in both HCFs and HKCs.
Conclusions :
Overall, our studies aim to advance the frontier of KC research. The data obtained from these studies will promote our understanding of the pathogenesis of KC and pave the way for the development of novel therapeutic targets.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.