Abstract
Purpose :
Glucocorticoids, such as dexamethasone (Dex), are speculated to alter the contractile properties of human trabecular meshwork (HTM) cells. However, there are no definitive studies showing that dexamethasone treatment modulates the contractile forces exerted by HTM cells in vitro. Because cellular contraction is a dynamic process, it is important to quantify changes in contractile force generation over time. Additionally, observed heterogeneity in primary HTM cell cultures call for single cell contraction measurements.
Methods :
In order to measure HTM cell contraction at the single cell level, primary HTM cells from 4 different donors were cultured for 5 days in the presence of DMSO vehicle, or 0.1µM Dex. After 5 days, primary HTM cells from each condition were harvested, dissociated to single cells, and seeded into the wells of the fluorescently labeled elastomeric contractible surfaces (FLECS) assay for single cell contraction measurements. Data were collected every 2 hours over a period of 16 hours and analyzed using computational algorithms.
Results :
Interestingly, a single large population of weakly contractile cells and smaller subpopulations of strongly contractile cells were identified across both conditions. The strongly contractile subpopulations remained smaller compared to the single weakly contractile cell population throughout the course of 16 hrs. Furthermore, the strongly contractile cell subpopulations became increasingly prominent in the DMSO vehicle condition throughout the course of 16 hrs. Dex treated cells also displayed small subpopulations of strongly contractile cells. However, these subpopulations were smaller compared to DMSO vehicle, and remained mostly unchanged throughout the course of 16 hrs.
Conclusions :
Based on our findings, Dex treatment appeared to reduce the ability of a population of primary HTM cells to exert strong contractile forces.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.